Hi team, not really an audio question but I know there are plenty of brains around here… I need a very simple current limiter / softstart for an 18v DC motor, just need to slow the initial turn on hit, half a second would be fine. Motor runs at around 3-4 amps but start and full load would be a lot higher. Thought about an NTC or a two position switch with a resister that could be inline for a bit then change switch position to direct (Cut out the resistor).

What do you think?

Cheers

I have a pair of Radian Neo745PB compression drivers and a pair of Ciare PR614 Horns to mount them on and I am looking to building a 2 way system to complement them and finally give them a proper home.

I am in search of a woofer to start the design process and since I am located in Italy it makes sense to limit the field to the great speakers made here. 18 sound, RCF, B&C, Ciare, would be easy to source here. Here is my active list in a google sheet which your invited to add anything that might be of interest. LINK

How to go about marching a woofer to these compression drivers? I am open to suggestions but I was envisioning a 10" or 12" woofer. How does the response curve, the efficiency, the power handling guide the woofer selection?

The setup will be BI amped with some Powersoft Q3002's and I plan on doing active crossovers with a miniDSP or a rack mounted DSP such as a EV DC-ONE

The intended use is for a mix of home stereo, portable DJ setup, band practice, and just general PA usage. The plan is to add a sub at some point.

The budget is around 160EUR for each woofer.

Volume wise I dont have a hard constraint but something in the 40-55 liters sounds reasonable.

What other requirements or constraints am I missing to nail down a driver before moving to the cabinate design fase?

Thanks

I have posted some simulations of the Bliesma T34A in a waveguide designed for wide directivity to very high frequencies, and some renderings of possible cabinet configurations using the Purifi 6.5 Aluminium driver in some other threads.









I am now making a concerted effort to actually build something that I can listen to 🙂

Finding time to finish the CNC I have been building (for a long time already) is proving hard and apart from aesthetics, I can make something simpler in appearance that performs pretty much as well with the already working tools I have. So a basic box with roundovers and a 3D printed removable waveguide will be the starting point.

Something more like this apart from the colour.



In case it is not obvious to anyone, I should mention that Ath from @mabat was used in the design process for the waveguide.

OFF: Pair of Dayton Audio DC50FA-8 Classic Series 2" Dome Midrange, with different front plate (Used the original front plate on an other set of dome mids), NEW, Never Installed...
Check the picture. I think the link shows the specs. Was sold originally around 49U$each...

Asking 50U$ for the Pair (or 70$CAN50U$) + Shipping

I can ship at the buyer expense, local pickup permitted.
If using Paypal, add 3.5% Paypal fee (or use for Friend and Family)

Payment cash in person or by bank EMT transfer.

No interest, already packed, ut won’t move them, they are going away…

Thanks for looking
SB

NC535 inspired me to hack up my B&C coaxes and try to improve them here : http://www.diyaudio.com/forums/multi-way/317000-synergy-post5300335.html

Which led to this thread : http://www.diyaudio.com/forums/multi-way/317064-prosound-coaxial-hacking-post5300366.html

While hacking up that coaxial, a couple things occurred to me:

1) The tweeter that's attached to my B&C coaxials has a FS that's too high

2) I have a couple of 3D printers, I'm fairly decent at 3D modeling, so why don't I just build my own compression drivers?


Here's my B&C DE5 compression drivers, which are part of the B&C 5FCX44 coaxial. You can see that it's a simple neodymium dome tweeter with a phase plug attached. Nothing too complex here.









Here's some pics of the phase plug that I made for my dome tweeters. This was my 2nd attempt, first one didn't work very well. It's largely based off of the tangerine phase plug used by Kef, which is an evolution of the Altec phase plug from fifty years ago.


Kef Tangerine


Altec Tangerine



Here's the response of a TB neodymium 29mm silk tweeter, versus a Dayton RS28. Both are using the tangerine phase plug pictured above, and mounted to an 18Sound XT1086 waveguide. You can see the TB performs pretty well. I don't know if I have a bad batch of RS28s, or if it just doesn't live up to the hype. I have four of them, can't get particularly good performance from any of them.


Here's a comparison of the TB soft dome with and without the tangerine phase plug. Not a massive difference, but definitely an improvement. This measurement is at an identical voltage, with CD EQ and a high pass filter.

I've spent the better part of the last year trying to make a speaker that could replace my Waslo Cosynes. I like the Cosynes a lot, but they're too big for my living room and my wife will certainly banish them soon.

I've made something like NINE attempts to replace it(1), and I keep failing. In particular, in my latest project, the waveguide was insufficiently small. Basically the speaker lost directivity control at 2khz.(2)

Frustrated by a pile of unfinished horns, I decided to do something different, and it worked out quite well.







It's the exact same drivers I used for Metlako and Celilo, but I'm uses a much smaller waveguide on the tweeter, and I've arrayed the midbasses.





The arrangement is largely inspired by DNA Sequence speaker. From the patent:/url]

"Few conventional speaker systems approach an ideal of a high efficiency point source directional loudspeaker system. In fact, most conventional speaker systems are low in efficiency, lack phase coherency, and do not act as an apparent point source system. A speaker system in accordance with the present invention closely emulates a single point source. Embodiments of the present invention achieve this result by an advantageous arrangement of transducers. The arrangement of transducers minimizes the amplitude of the sound waves that can cause room reflections and the resultant distortion therein."

(1) [url]https://www.diyaudio.com/forums/multi-way/342019-metlako-affordable-unity-waveguide.html

(2)Celilo : A Small, Affordable Two-Way Unity Horn

EDIT: Added location info.

I've been away from diyAudio for quite some time after work and life got busy. Now I need to relocate for work on short notice, and I need to downsize. It's time to let the half-dozen half-baked project ideas go to folks who are more likely to do something with the materials. Really, I should have done this a long time ago.

Right now, I'm just looking to move a whole bunch of drivers. They take up the most space. Don't really know how to price all this stuff, so please just make a reasonable offer, otherwise this stuff is going in the trash and that will suck. But it's not moving with me. Be sure to account for the actual cost of shipping from 98682. Some of them are a bit heavy, but I'd say I could probably ship any one set to you anywhere in the USA for about $25, maybe less. I will give you the lowest actual cost I can get for ground shipping through either USPS or UPS. Let me know if you have a preference for one service or another.

Local meetup in the Portland, OR metro area is OK.

Payment via PayPal

Everything has been stored in its original packaging indoors in climate-controlled environments, but please note that most of this stuff is probably 15 years old.

I didn't want to overload this post with pix, but you can see pix of everything here:

diyAudio For Sale (imgur)

DM me or post a reply to this message if you're interested in anything.

Thanks for helping me clear out my closet!! I'll be sure to update this post as things get claimed.

FOR SALE
----------------
SOLD Qty. 8 Dayton Audio DA135-8 5" Al Cone Woofer
SOLD Qty. 4 Dayton Audio DA175-8 7" Al Cone Woofer
Qty. 4 Tang Band W3-1335SB 8 Ohm Titanium Cone Full Range
Qty. 2 Hi-Vi B4N Al Cone Midbass
Qty. 4 Tang Band W3-315E Al/Mg 8 Ohm Full-Range
Qty. 4 Tang Band W3-593S 8 Ohm Paper Cone/Al Phase Plug Full Range

Hi guys

This GB has been setup for the Thread : "The Very Best Amplifier I Have Ever Heard!!!! " # 174468



Please make my work easier by leaving information as follow :


Subject : PCB order for Goldmun clone
Content : <forum ID>;<email address (paypal a/c)>;M-99;P-99

There might be still some uncertainty about the pcb. But the price will be right if no change in pcb size.

Cost for protection PCB estimate to be $8 (should not exceed $9)

Will post status everyday after Oct 15

I've noticed that people have been printing out some of my waveguides, even though I never managed to actually finish a project. I've probably made five hundred things over the last few years, and many never even wind up getting documented, much less uploaded.

So I thought I'd pull up a few and post them.

Like a lot of my stuff, these things are a "work in progress."

You may need to do some reverse engineering, or just print the thing and see if it works.

I'm generally pretty good about getting the fit right, so most of these should fit whatever driver they're intended for.

I also have a github, but that interface isn't the greatest.

Instructions to use my GitHub here: https://www.diyaudio.com/forums/multi-way/342019-metlako-affordable-unity-waveguide-post5908380.html

Hello I have a gem rodeo 49 keyboard. I am looking for a wiring diagram please. Thanks

Theoretically, it's not possible to make a small, affordable two-way Unity waveguide.

The problem is the midranges:

There aren't many midranges that work well on a Unity waveguide. The ones that are usable tend to have a high FS and a low QES. Due to this, it's very challenging to get a suitable midrange to play lower than 300Hz on a Unity horn.(1)

Over the years, I've tried a gazillion different shapes for the midrange taps on a Unity waveguide. I settled on a shape that's largely inspired by the shape of the L'Acoustics DOSC. Basically the entrance to the tap is circle, and the exit is a ribbon. (2)

This specific shape allows for something seemingly impossible in a Unity waveguide, which is that you can 'push' the midranges to play much higher than they normally would.

With this innovation in mind, I wanted to find out if it's possible to make a small, affordable two-way Unity waveguide. The theory says it can't be done, but sometimes you can bend the rules.





Mabat's software is truly a game changer. It's literally cut down the time I need to make a waveguide by around 75%, and it's also allowed me to simulate them before I design and print them. It's unreal. (3)







I came up with a new way to 3D print a waveguide that allows you to make one that's about twice as large as normally possible. Basically I slice the waveguide in half, and then I put one half inside of the other, like a Russian doll. The black waveguide was the biggest I could formerly print on my printer; the orange waveguide, hot off the printer, is about twice the volume. Same printer.

I have no idea if this is going to work. If it DOES work, it will simplify the process of making a Unity waveguide. Basically you will be able to have the midranges cover the entire spectrum. It will be a two way instead of a three way.

There HAVE been variations on this idea before:

1) Sound Physics Labs sold the "SPL Runt" which is a two way Unity horn. I could have gone that route by using a more expensive compression driver and midbass. Basically by using a midbass with a high FS and a low QES along with a compression driver that can handle some abuse. But I wanted to keep this project cheap; the total driver cost for all five drivers is under $75. Copying the SPL Runt would have quadrupled the driver cost, plus I don't like copying things 🙂

2) XRK did a two-way by putting a full range SB Acoustics at the apex of the horn. By basically pushing the tweeter down lower he was able to get it to play full range. Very cool! It blew my socks off when I saw it.

3) Art Welter has a two-way MEH horn that follows a similar recipe as the SPL Runt. (High FS and low QES on the midbasses along with a beefy compression driver.)

But I'm trying to take a different route, I'm trying to see if the geometry of the midrange taps can be modified to a point where they'll play full-range.

I don't know if this will work, but I'm eager to find out!


(1) https://www.diyaudio.com/forums/multi-way/88237-suitable-midrange-cone-bandpass-mid-unity-horn.html

(2) https://www.diyaudio.com/forums/multi-way/319698-unitized-image-control-waveguide-3.html

(3) https://www.diyaudio.com/forums/multi-way/279476-3d-modeling-tips-tricks-post5858286.html

When I tried to adjust the bias I touch with the tip of the multimeter in one of the power rails and two fuses blown.
I replace the two fuses but every time I put the power on the same fuses blow again.
I'm not an electronic expert but I like to have some guidance from you guys and try to repairing it.
I'm only using the power section of this amp with a Yamaha pre-amp, but I do like a lot this power amp.
Thanks in advance.
Lica.

I love all things audio related and I follow you guys for years.
Cheers from Portugal.

I was wondering if some people could recomend me a better peforming drop in replacement for a 741 Op-AMP. I would prefer if it come in a surface mount package rather than a dip.

Experimented with alternate enclosure materials, shapes, configurations e.g. tubes (pipes),
wood, concrete, ceramics, glass, rubber, etc. Will search archives and will post photos and specs.

Thank you again for this opp.

1 - Fosi Audio ZD3. like new. comes in original packaging with all accessories and remote. everything like new. comes with two sets of op amps. comes with a set of XLR interconnect cables. $133.33 shipped friends and family

2 - CANARE 4s11 speaker cable. NEW. Gray. I have two cables segments. one in a little over 24 feet and the other a little over 12 feet. price all together $88 shipped friends and family

3 - bundle of random DIY components $44:
1- Quantity = 6 WBT RCA connectors
2 - quantity = 4 Neutrik XLR connectors. not all neutrik ins the same. this is the top of the line gold plated connectors black color premium ones.
3 - quantity = 2 DC power connector large
4 - quantity = 2 DC power connector thin
5 - quantity = 2 DC power connector medium
6 - 20x 1uF mica capacitor for power supply
7 - power on/off switch with LED indicator
8 - power on/off switch with LED indicator
9 - brass ground connector
10 - quantity = 4 ceramic tube connector
11 - aviator connector for building DC power supply 4 pin
12 - aviator connector for building DC power supply 2 pin
13 - quantity = 2 IEC power connector with fuse and on / off button
14 - big AC power distribution with usb A and C
15 - gold plated copper sliding connector with shield around 40 quantity

everything together $199 shipped conus paypal friends and family for EVERYTHING

pics:
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This headphone amplifier should suit impedances 8-600 Ohm.
The distortion is very low. It could be called HiFi.
Potentiometer to adjust output to 5.50 Volt.
The bias should be like 100 mA.
Supply is 12 Volt DC.

I'm not exactly new here, but I haven't been on in a LONG time. I'm kinda a DIY audio nerd, I built a pair of CBT36's a few years ago and am looking forward to building something new to replace them. Looking forward to the convos!

In the 'search' for jFETs I found a hybrid SIC jFET: UJ3C120150 K3S
It is a 'normally-on jFET' combined with a driver mosfet:

This SiC FET device is based on a unique ‘cascode’ circuit configuration, in which a normally-on SiC JFET is co-packaged with a Si MOSFET to produce a normally-off SiC FET device. The device’s standard gate-drive characteristics allows for a true “drop-in replacement” to Si FETs, SiC MOSFETs.

Click to expand...

1200V. 10A. >120W. zero input capacitance (sorry I dream: Ciss is actually rather high, then can't they handle that embedded driver better??). But at least: the curve is that of a jFET.
Has anybody any experience with this in the PASS community?
Or is it secretly an iGBT?

* SOLD *

A pair of Yamaha JA6681B compression drivers featuring their famous patented diaphragms.

Close Serials #104036 and #104065. Original diaphrams visually inspected. Close coil resistance 12.6 and 12.5 ohms.

The absorbing foam (black) is present in one cover and was cleaned up from the other. Note that this foam disintegrates over time, and is best removed. It looks like one diaphragm was resoldered. Perhaps it was removed to clean up foam particles? (I am guessing).

Most important: The fingers of both diaphragms look fine: none is broken that I can see.

By mistake I threw away the front gasket of one of the drivers... A DIY replacement would do.

These outstanding drivers are becoming hard to find. Look at the reviews. For those of you who already own the JA6681: buy these as spares!

What's a fair price?
Let's say: drivers including diaphragms: 690 USD + shipping

North America preferred.

Pierre



https://photos.google.com/photo/AF1QipNztMmcvfnCAusyUvT7JbHjKEbaGxlX2HF4CifF

https://photos.google.com/photo/AF1QipNztMmcvfnCAusyUvT7JbHjKEbaGxlX2HF4CifF

https://photos.google.com/photo/AF1QipNztMmcvfnCAusyUvT7JbHjKEbaGxlX2HF4CifF



https://photos.google.com/photo/AF1QipNztMmcvfnCAusyUvT7JbHjKEbaGxlX2HF4CifF

https://photos.google.com/photo/AF1QipNztMmcvfnCAusyUvT7JbHjKEbaGxlX2HF4CifF

I'm in the designing phase of a 2-way setup with 1.4" CD and 10" Mid, with a passive crossover. My goals are 100-110db but prioritizing Sound Quality over anything. My last build (3way with decent drivers) was 2 years ago and I want this to be my final build and meet all my desires.

I intend on going with the 18Sound-10NW650 as my Woofer in a 1cuft vented enclosure tuned to 65hz, and the 18Sound-HD1480T CD with their XR1464C waveguide crossed at 800hz -ish.

I chose these drivers because I have a likeness towards 18Sound as a brand and grew up with the sound of their drivers, I've also had great personal experiences using their midrange drivers in a Car audio setting. That being said I'm not going to force myself to stick to their drivers exclusively if I have options that are far superior. I'm also considering the 18Sound-ND1460 and 18Sound-ND4015Ti2. From what I've gathered the ND4015Ti2 is much newer and also more expensive, I would like some input on if its worth it over the HD1480T. (Based on what I've read, I believe that it is likely worth it)
For the Mid I was also looking at the Beyma-10MC700ND, its more expensive than my intended 18Sound-10NW650 but it modeled similarly in a similar airspace. I would like input on if the Beyma driver would benefit me in any aspects of SQ over the 18-Sound driver. I intend to cross at about 70hz to my Sub.

For the Passive Crossover I plan on using a Linkwitz-Riley 24 dB/octave on both high and low pass. I did consider going with an active crossover since I use a MiniDSP Flex as my preamp but I don't plan on spending the $ on another MC7270 to pair with my current one, or buying new amps entirely.

I have no experience working with Compression drivers but have learned a lot from reading. Any advice for the build is appreciated 🙂

ZM has been nagging me for information on the F6. I have a very nice
sounding prototype, but the design and the article that accompanies it
have some details remaining.

However, I can afford to put out this teaser:

😎

May we ask for the Circuit Diagram, and the how this looks at the back of the PCB (PCB Diagram)? We're using it for school, and having the circuit diagram, and its connection in the PCB will be a great help. Thank You!!!

Hi !, I need some help fixing a Technics SU-V660 amp, ( it uses the SVI3205 ic that I read I can't get anymore to replace it ).
Amplifier turns on but no output , the speaker relay does not turn on.

• The switches for A / B output work
• No short circuit on the ic outputs
• No short between the outputs and the Voltage rails

So I doubt the transistors in the ic are burnt.
Might be a problem with the protection circuit ? The SVI3205 ic does that ? , turns on / off the speaker relay.
Any ideeas what to do ?.
Relay measures fine, maybe the transistor and resistors around it needs to be checked.
Thank you, Bruno.


Service manual here:

⭐️So I want to Thank everyone who has bought from me so far. I greatly appreciated it. 💥So for a new update I’m Giving some new lower pricing on the Mark Audio and Fostex Speakers. I still have all the Gotham Cables for sale and more. I can meet up if need to. You can e mail with questions and offers at my E mail at the bottom of the selling post. You could make me in offer for every thing if you wanted to am not opposed to working something out. So Am still doing spring cleaning.

Pending/ 1.Mark Audio MAOP 11 Drivers. A new set never used or tested. Still on the box they came in. Am asking $300.00 a pair and buyer pays for shipping To the 48 United States.

Pending/2. Mark Audio Puliva HD 2 drivers in the copper color. Brand new in the box never used or tested. Am asking $50.00 for the pair and buy pays shipping.

Sold/3.Fostex FE126E and FE126NV Drivers Brand new Never used or tested. Stored in a good room. Am asking $125.00 for both pairs I will pay for shipping to the 48 United States.

Pending/4.I still have the Dayton Audio RS125 Aluminum Drivers in 4 ohm. In the box brand new never used. Am asking $40.00 a pair and you pay for shipping.

Amplifier and speakers together as a set for sale. Dayton Audios Blue Tooth 65 watt amplifier for sale with the Studio 20 speakers. Am asking $85.00 now. Local pick up or I can meet up. Shipping would be on the buyer.

Pending/I still have the frugal horn XL for sale. Completed. Binding post and wire you have to do your self. Dayton Audios binding post plates and new top of the line dayton Audio binding post. A $70.00 Value still in the blister packs. Dayton 13 gauge (o.f.c.) wire. You get 24 feet of it. as well. Am asking $80.00 for the set of boxes with all mentioned. I can meet up. Shipping would have to be up to the buyer.

Cables Still for sale.

RCA Cable for sale.

4. Mogami 2524 Wire at 24 feet $0.86 x 22 =$18.92. Am asking $10.00 for this cable.

Speaker wires for sale.

1. Redco 12-2 C-2 12 x2 Gauge wire $1.25 x 50 feet= $62.50 I paid. Am asking $37.00 for this cable.


Mogami

1. Mogami wire (o.f.c.) hook up wires 1 red 1 blue. I paid $60.00 dollars for both of them. Am asking $30.00 for the set. 50 feet each.

Other speaker cable brands for sale.

A..Whirlwind 4x12 cables at 26 feet $4.55=118.3. Am asking $80.00 for this cable.

B. CBI Power series 12x 2 cables at 22 feet $0.91 cents for $20.02. Am asking $10.00 for this cable.


Sold/ Belden 1313A 10 gauge 10x2 speaker cables 54 feet $3.30 =$171.60.
Am asking $100.00 and buyer pays for shipping. Thick heavy cables.


West wire I believe I bought a Redco a while ago. $0.45 cents a foot at 22 feet =$9.90. Am asking $5.00 for this cable.

Gotham Speaker Cables.

1.(50010) SPK 2x1 30 Gauge wire at $2.45 a meter. 52 feet at 15.82 metersz . I paid $ 38.38 . Am asking $20.00 for this cable.


2.(50150) SPK-GAC 13 gauge shielded wire. $6.00 a meter. 38 feet of this wire. It’s 11.582 meters. I paid $69.49. Am asking $40.00 for this cable.



3.(50025). SPK- 2x2 13 gauge wire at $4.75 a meter. 42 feet of wire. Is 12.802 meters $ 60.00 my cost. Am asking $35.00 for this cable.

4.(50040) SPK 2x4 11 gauge wire at $6.96 a meter. I have 47 feet and 14.326 meters of this wire 14.326 x $6.96 = $99.27 my cost. Am asking $70.00 for this cable.

5.(5026) SPK 2x6 9 gauge wire at $8.95 a meter x 18 feet =5.486 meters $49.10 selling it for $42.00 for the cable. I also have a 28 feet of this cable as well = 8.5344 meters $76.38. Am asking $50. 00. I will pay for shipping for these cables.

(Updated) 6.(50080) 2x8 8 gauge wire 8x2 at $16.30 a meter x 24 = $391.20. The heavest cable I have to sell. Come on a spool in a gotham Audio box. Am asking $290.00 and buyer pays for the shipping.

A.C. Cables.

1. (85055) Gotham Audio GPC 3x5 4 meters x a meter $24.85 x 4 =$99.40. am asking $70.00 dollars and I will throw in an a second (85005 cable ) 10 feet I will give with buying the first cable.


I have some new speak on connections with seals and connections for the speaker wires and input speakers ons. you speaker box as well. I paid around $70.00 Am asking $40.00 you pay for shipping.

Wire hook up connectors

I still have a lot of Banana plugs and spades and rca cable hook ups. Please E mail me for quality and brand. I have Dayton Audio and Gotham cable and street wires and another brand. I also have wire dressing up for cables and heat shrink tubing and y boots for speaker wire making.


I still have the solder fume fan and Digtal weller solding station still for sale. I have extra tips for the solding station. Am asking $100.00 for both. Buyer pays shipping.


I also have a heated dryer with different air tips brand new never used station as well. Am asking $50.00 for it. Buyer pays shipping.


Sold/I still have The Dayton Audio Dats v3 mint condition and I will thrown in the bass box pro and crossover pro with and the Winspeakerz all for $100.00. you play for shipping or we could meet up.


I also have the original woofer tester 2 and I will thrown the Subwoofer tools box program in a Tri pod and an acoustic egg piece with it as well. Am looking for $60.00.
Local pick up or meeting would be great.

Please E mail with questions on offers and shipping. Thanks for looking. Jeff

I bought some weeks ago a cd303 player, partially recaped, and in a general decent order (I think the dude said something about the drawer leds-i don't know). As I am one of those guys that blanket recap all things I dismantle the thing to make a list.
The surprise come a little later when after assembly started to sound very "synth-like" and craped out-there is a possibility that I inverted the "data" and "psu" lines from the servo bord, I did color marked the sockets... - can't really confirm it- but hey, not the first time that I did something stupid.
I did put some Caps back on the bord telling my self crazy reasons for it 🙂) but no the CPU from the servo was dead.
The worst of the worst a old rare cpu- and factory programed - at first I found in soume posts and video clips a dude that had a "soundtraces" blue bord with a atmel chip on-no luck there, never find who actually sells them. But again I stroke some luck and find a set of servo + decoding boards the seller accepted my offer and I was back I business.
Just replace The MAB 8440DP D011 and he plays once again.

(I know most people don't like full recaps but I do, on my original boards or the replacement ones there where not of the philips axial blue electrolyticss in good shape except the 1uF ones all half the value and with a esr of many many many ohms)

I have to say I bought it to recover some parts from it, as a while back I seen some dac boards that required this dac (tda1540)...

But now. OMG that mech 🙂) .... How can I not like it? and anyway not I have another two DACs and filter that at this moment have no reason to believe that they don't work.

Now:
Need to dismantle it again and clean it as it still dirty and I hate having to pealing dead foam with my finger tips.
Adjust the drawer as it is not quite centered
Find and Replace ALL el-caps from drwaer board and laser board + fine tune the laser (don't know how-I have the tools done it before but with a much better service manual... one that I could read🙂) )
Find a solution for the annoying the in the clip : Login to view embedded media I don't like the look of the orange or axial film caps eighter- I will pull some for proper testing
Decide what decoding board is "better" type C or type A and If they are replaceable without having to retune things...
I had something else to say-I forgot.

Any thoughts you have to share will be gratefully received.

Ultra high spec. opamp MC/MM phono, warp "elliptic" filter, line, headphone amps.

This is a project that has been on Audio Karma for about a year and has had a number of revisions, additions and upgrades.
There are about 150 of the units in various versions out in the field and it was repeatedly suggested by builders that a thread be opened in DIYaudio- so despite some reluctance here it is.
As the title suggests, it is opamp based, and is hardly unique, but it has some unusual features and has stellar specs and is pretty easy to build.
Some features:
1. Optional parallel input amps-
2x LT1115/AD797/OPA1611 or OPA1612 for MC
2x OPA1641 or similar or OPA1656/OPA1642 for MM
Cartridge load components can be altered without soldering.
2. 75us TC in input stage to optimize overload characteristic- approx. 28dB at rated -9dBv output at all frequencies up to greater than 50kHz with +/-15v supplies.
3. Additional standard RIAA TCs in output stage.
4. Gain partitioning/opamp choices made to keep negative feedback factor high over the entire audio range to minimize high order harmonics and many tone IM distortion.
5. Interstage TC added to compensate for the transition to unity gain of the input gain stage to maintain RIAA characteristic compliance. No unity gain transition in output stage due to choice of architecture.
6. DC offset correction in the phono output- so no coupling caps.
7. Polypropylene caps used in all of the signal paths.
8. Off the shelf SMPS used with input LC filter.
7. Extensive on board power supply decoupling.
8. MC and MM versions can be built with some component changes.
FET input opamps for MM version. Bipolar for MC.
9. 62dB gain for standard MC stage, 42dB for MM. Nominal sensitivity- 250uv @1kHz, 5cm/sec for the MC, 2.5mv for the MM.
10. RIAA simulated compliance c. 20mdB p-p, 20Hz-20kHz. Measured with non selected off the shelf components to be <50mdB p-p. Simulated worst case <100mdB p-p.
11. Unmeasurably low (limited by measurement system) distortion at rated output, including harmonic and many tone.
12. Phono Warp first order "elliptic" filter with vertical (L-R) rejection of c. 3dB at 140Hz and c. 36dB at 2Hz. Nominally 0dB rejection of horizontal (L+R) rejection.
12. Additional 10dB gain can be selected in the warp filter section to increase overall gain to 72dB/52dB.
13. Buffers for volume control and line driving added, 47 ohm output impedance.
14. Mono switch, no balance control.
15. Optional balanced output drive, 47 ohms/side.
16. Optional (separate board) OPA1656/LMH6321 headphone amp. On board heatsinking. Can drive loads as low as 16 ohms. Unmeasurably low distortion. Output impedance c.0.1ohms. 6dB gain.

Measurement system. RME ADI-2 PRO FS R with REW.
High quality boards available. Schematics, measurement results, BOM and build guides available.
Any interest?

I was looking for the most simple EL84 circuit to get started and found something like this:
http://www.diyparadise.com/simpleel84.html

Am I missing something or is that website missing something or is it really possible to build a working PP amp with one OPT, two resistors and a pair of EL84? Has anyone tried it? What's going on here?

The schematic:

Hello- here to learn and build.

Apparently this was around Thanksgiving of last year. Jim published some white papers about Line Arrays, and additionally liked building TLs and open-back projects. He was a gentle soul, and I met him back at my first speaker event in Dayton in 2002, where he demoed the Linus Arrays.
https://www.hhhfunerals.com/obituaries/james-griffin
He will be missed...

abandoning a project , i have a brand new pair of VOLT VM527 2inch dome driver to sell , never mounted , never used.
my loss is your gain .

wanting 450€ for the pair including shipping to E.U only
thanks for looking.

Hello, please help me to model and determine the behavior and distortion of adding a second shorted identical loudspeaker in a sealed box (vas 24l, fs 39hz, volume 20l) as passive radiator.

I tested because i had a spare identical loudspeaker around, and I like because I have very clean bass now, but not really sure how to model, and if I could damage the second speaker due to shorting its terminals.

I think it should be something like a sealed box with losses, something like a variovent, or a bass like air flow resistor.

I am looking at building the Kegger / Blueglow KT88 SET amp and I would like to see how well I can make it perform with upgraded parts. And, well, it is probably not fair to say I am willing to spend every dollar possible on it, I am open to a significant investment.

I plan to start with Hashimoto output transformers, power supply and choke. For the coupling capacitors, I purchased Duelund CAST PIO SN-CU. I am also considering adding Audio Note silver tantalum non-magnetic resistors and Cardas binding posts.

For those who built the amp or have thoughts regarding the circuit design, what else would you upgrade? Would you only use AN tantalum resistors in select positions? I have also heard carbon based resistors are better for the grid and wire wound resistors are better for the plate load positions, do you agree and have recommendations re brands?

I am newer to building tube amps, but I have a fair amount of experience in HiFi and have a very resolving home audio system. This is my reason for wanting to maximize the design.

Thanks for your thoughts. Here is a link to the BOM Mark shared. A big thanks to him for all his work on this version! https://blueglowelectronics.wordpress.com/diagrams/

Selling my Jabo 53 tractrix horns. I have been very happy with them in my active system. I have divided them 800 - 4500 Hz in a 4-way setup, but you can easily split it from 350 Hz and up into a 2-way.

Entry 2". Length 32 cm. Weight 3 kg per piece.

Adapters can also be included. This has a 1.4" to 2" neck.

I will pack them well and will ship them in 2 separate packages. Please contact me for exact shipping costs.

Price $300

Hello everyone! Hope you're doing well.

I recently bought a Philips CD303 that couldn’t read discs, and after a complete recap of all the boards, it seems to have come back from the dead.

When I first got it, the player powered on, but the disc would spin a couple of times very slowly and then stop. After replacing all the capacitors (Power Supply, Decoder, Servo, CDM0, and Side Panel boards), it now reads discs and plays them perfectly. The biggest improvement came after replacing the capacitors on the CDM0 board.

While I’m thrilled to have brought this gem back to life, there’s still one issue I’d like to share with you all in case someone has any ideas about what might be causing it.

When I turn on the player (cold), the disc starts spinning very fast for about 1-2 minutes. After this time, the disc stops, and pressing PLAY starts playback without any issues. It feels as though some component needs to "warm up."

Additionally, while playing a disc, the playback occasionally (though rarely) stops, and the disc halts. However, pressing PLAY again, playback starts again normally without further issues.

Here’s what I’ve observed:

• The SAA7030 chip gets very hot, reaching almost 60°C.
• The SONY CX7934 chip (the slim chip located on the additional board of the decoder PCB) gets even hotter, reaching around 66°C.

What’s interesting is that if, for example, I listen to music and then power off the unit, letting it cool down for about an hour, the same behavior occurs when I turn it back on: the disc spins very fast for about 2 minutes, then stops, and playback starts normally. However, if I power it off and back on again after just 5 minutes, I can play discs without going through the fast-spinning phase. It really seems like some component needs to reach a certain temperature.

I also own a working CD202. I suppose I could try swapping chips between the two units, but honestly, the thought of opening the CD202 drains my will to live… I hate those metal cages around the boards!

Any help or suggestions would be greatly appreciated.

… or: is it possible to attain more than 200W from an amplifier based on LM3886 IC

Here is another project from my workbench. I was very pleasantly surprised with several amplifier projects based on chip amps, LM3886 and TDA7293. However, the main obstacle using these ICs is moderate, or should I say, lowish power output, about 60W per channel.

People persistently complain about the “poor bass” but I don’t think that the IC is the culprit. Inadequate speakers in combination with poorly designed amplifier boards are likely responsible for the LM3886 bad reputation in low frequencies. My measurements indicate otherwise: the IC is OK itself but it deserves better “working conditions”.

Obvious solution is paralleling and bridging, but, it isn’t so straightforward. Due to the lack of knowledge I have decided to use an existing design and turn it into a decent and powerfull amplifier. My choice is YISHENG LM3886 BTL Amplifier Board which implements paralleling and bridging to attain High Power High Fidelity performance.

One channel of this board is presented at the snapshot below. A lovely design, if I may say. I haven’t tried yet to reverse-engineer it. My intentions are much more modest. I want ro investigate the real world performance if this board and how to use it as a Hi-Fi amplifier.

First, I have investigated frequency response of the board and I have found out that test results are great indeed. Also, I have tested square wave response which are quite adequate.

Now, I'm testing its endurance on 200W 7.3 ohm dummy load. For time being I was able to run it at 125W constant 1KHz signal. I do really push it at the limits of thermal endurance.

Otherwise, the board is a real beauty, very well designed with wonderful layout. It is going to have from me a beautiful chassis.

More to follow...

Meanwhile, I have uploaded more photos of the amplifier board from my bench.


Please note that the board utilized four OPA2605 opamps and two pairs of transistord: 2sc2383, 2SD669, 2SC649 and 2SA1013. It appears that it is a bit more than paralleling and bridging. Let's see what it is

I'm in search of a decent PA/hifi type 18" LF/sub driver for a vented 160L enclosure aiming for -3dB @ low 30s. It would be nice to have 95+ dB sensitivity at an acceptable xmax to achieve at least 115dB down to F3 and possibly good F10.

Budget is up to $400-ish and available here in the US. Been looking at the B&C 18TBW100 and 18TBX100 as possible options. Neo would be nice but a ferrite motor wouldn't be out of the question. Already tried the 18NW100 but its specs weren't as advertised.

I've looked at the so called 18" Marty Cube design, which is roughly what I wanted but I'm open to anything comparable. I prefer vented over the popular horn loaded TL for more accurate, tighter low end. A larger vented box is a good compromise IMO.

Please reply here with any suggestions in line with my preferences and goals.

Last time, the danish sold me loudspeakers with fake plastic chassis that was really made of cheap magnesia cast. And now they're telling me that crumpled foil could add enough of stiffness to make a loadspeaker functioning.

Any opinions on that?

Assuming the +/- 20% of radiating piston area deviation claim is a joke to focus on possible relevance of cone surround (see partial screenshot from dayton ultimax indicating hat piston area doesn't really change due to rolling, but at the same time, getting stiffness force roughly linear in [un-]rolled area), what about aging crumpled foil then? According to wavecor measurements, even standard formed surround appears to have notable initial stiffness change.

Hey everyone! I learned about this website through the thatmicpre project, and I like music-related things. I'm a newbie in other respects.

I had built a pair of 2ways about a month ago but had bought some pre-built crossovers. I have since been tying to learn how to design the xovers myself. By far the most difficult part of the process imo. I think I have it at least close and would like to get some opinions. I'll post a screenshot of the graph and a parts list. Also, there are no resistors in this design but I think I dont need them? I want to cross at around 2500. Anyway, any and all help and/or guidance will be appreciated. I will note that even though the video I watched on how to use this particular program said to use tweeter/woofer when doing a 2way. It wouldnt recognize my woofer unless I used TM. I'm sure its something I'm doing wrong but the results look like it might be done right?

WOOFER TWEETER
Ind: 0.76 Cap: 13.48
Cap: 10.76 Ind:0.87

Hello friends, I have acquired a music center which has 3 LM 1875/TDA 2030, one for the sub and the two satellites. It has volume, bass( sub level) and treble ( that comes handy for certain records...err..streams ) plus a 2 mics&echo control ( yes, the karaoke feature).
The subs that I built this summer come handy too. The little satellites that I built purposely for my BT thingy are 16 Ω ( they are useful for the tube amp, though they lack bass ) and with the class D amps of the BT thingy they perform ok (the BT thingy doesn't do highpass for the sats).

Now...I have acquired a Sony portable radio/CD/cassette player that incorporates those convex speakers.
I have two ex-speaker membranes from which I made two 8 waveguides.

The convex speakers are 3.2 Ω
The midwoofers are 6 Ω
I have some coils & caps laying around, so a series filter was made. 6.8uF + 2 mH ...sounds good.

Ok, to be finished...but don't have time! Jocking...just deciding what to do ( throw everything in the garbage! No, that's where it comes from...!)

I'm looking for a high quality mil-spec/industrial type vendor for boards. This is work related, not DIY related.

We all know the quick turn proto houses and I use them but for this I need;

600mm x 600 mm

G10 or G11 material

10+ oz/in thickness.

nickel plating would be great.

This is low quantity.

Thank You.

Looking for some KSA1220AY. Anyone has spares to sale? I am in CA, USA.

Thank you.

I'm building a Nakamichi OMS5 from a couple of parts units. One was dropped and has a major failure in the HLPL 030020 laser assembly - the prism that directs the beam fell off and was sitting in the bottom of the case. I'm curious if anyone out there could repair and realign one of these rare birds so I could have an as new laser - it would be nice to have the diode and photosensor replaced for a fresh start.

good morning afternoon everyone, as I'm getting older I need quiter hobbies and audio always been there for me, in house, in car. I prefere very much DIY solution and built several BLH speakers myself and some pre/amps. thank you for the great community and great deal of advise always free in this forum

There was an article in Nuts and Volts (10 2013) about a headphones amp with op-amp topology and class A output. Claims pretty good performance. The transistors used (except for the power stage) are 2N5551 / 2N5401. Those are high voltage transistors. Would be a good choice for high voltage power amp design, but this headphones amp is powered by +/- 12V.

Is there something else about these transistors making them particularly good here? Or general purpose transistors like 2n4401 / 2N4403 will work the same?

Have you shipped heavy stuff with UPS, FedEx, USPS?

Even gotten an amp with bent fins, broken off handles, and worse... once I got a pair or small speakers that had broken woofer baskets!

Often the box looks reasonable on the outside, and the stuff inside looks reasonable well packed... but somehow... they broke something off.

And putting a FRAGILE HANDLE WITH CARE sign is just putting a bullseye on your box. It says, hey... drop this one from only 12 feet, not 20...

In the DIY world, I wonder why we can't get a double box package when we buy the case from Modushop. Some manufactures sell you that and shipping is not too bad as the empty boxes are light enough. This works with lighter stuff like preamps... but with 50 lb amps....

Anyhow, the last heavy amp I received was really well packed. Kudos to Randy. That was a 4U, 400mm box. Maybe he should post the "schematics"... Some plywood, some straps, surround it with foam and put it in suitable large box with lots of duct tape. It worked very well.

Hi, I was building new enclosure for my Kef Q150 drivers, I tried to take the crossover out by too much force and snapped one in half....... What are my options here? Not sure how I go about making a new one or repairing it. Cannot see anywhere where I can just buy a replacement?

Any help much appreciated, thanks

İtt 8025
Teac A460
Pioneer Ct-f650
Sony Tc15f

I want to buy one of these cassette players. Similar Prices.

Which is Better?

Interested in DIY turntable and tone arm

Hello,
Over the past year or so, I've been fixing up some of my old electronics that were lying around. Completely restored a ReVox B750 Amp that I rarely use, new belts on a Beosystem 2500, full recap on a Bose Wave, and recapped 2 Squeezeboxes. One of the sqeezeboxes I can't get working, so I'll keep it as a parts unit for the display.

Next, I want to look at a Sony CDP-89ES that skips and an Enlightened Audio Design (EAD) DSP-7000 Series III DAC.

Hello Everyone,

I would like to introduce to you a new project of mine: wtfplay.

wtfplay is my attempt to create minimalistic Linux based, PC music playback
environment. Initially I wrote the music player software from scratch, later I built a
dedicated Linux distribution for it. It is called wtfplay-live.

wtfplay-live is optimized for playback from local disks. Its main features are:

• memory based, bit perfect playback of stereo PCM files (WAV and FLAC), 16
  and 24bit, up to 384kHz.
• command line driven - no graphical mode, no network.
• runs completely from RAM, all local disks are accessed in read-only mode
• distributed as LiveCD ISO image that can be written on the optical disk as
  well as onto a memory stick, SD card or hard drive.
• runs on Intel Core2 Duo and newer CPUs.

In this project, the top priority is the sound quality rather than a number of
features.

Try it and let me know what you think. The downloads and the documentation can
be found at wtfplay-project.org

Please note that wtfplay-live is still under development and new features will
be added to it.

Also note, that wtfplay project is something that I do as a hobby in my so
called free time, so be easy with the amount of questions asked 🙂

frd

Currently building this crossover Id like to use it for subs.
What Size caps will I use to Have a 20 hz Rollover point?

I bought 3 Peavey CS-800 amps. All have issues. Strangly enough, they all do the same. I replaced the fuse, and plugged it into my DBT. The light glows bright, and dims down.

But when I connect a speaker to either channel, the bulb is bright as can be and stays that way. The speaker is fine. They were all caked in nicotine dust, and are all clean. So its happy and stuff. I don't want to take it off the DBT, because I don't want to kill the amp.

I'm using a 100W lightbulb. This is the original PV-800. It is the same model as the one shown in this picture. (I got the pict off Google, its not my actual amp.



The traic boards are fine. Should I start checking the outputs for shorts?

-Nick

Hello I am new to the forum. I am an electronics student I repair audio amplifiers, televisions, keyboards and musical instruments.

Good Day to all Acoustat experts and enthusiasts : I have 2 pairs of Acoustat Z2010s which i want to use but i don't have any power supply adapters for them.
I know they need to be driven by 9 Volt AC but i would like to know the current strength of the necessary power adapter. If you could please assist me with that please.
I will have a ton of other questions for my set-up but for now i need power first ,lol. Any help is greatly appreciated. Thank you

I have 8 other phono stages and the tonal balance of my Naim Stageline K is a bit on the bright side but it suits my Linn Troika or Karma cartridges quite well on a precirkus LP12. Balances out quite nicely and there is some synergy going on. It gives the music some nice drive and dynamics - with the PRAT philosophy.

However there is an obvious problem in a lack of low bass to my ears. I know Naim circuits are bandwidth limited to some extent in both the top end and low end but to me it sounds like everything below around 40 Hz is missing, compared to all the other phono stages I’ve got. I assume it must have quite a shallow high pass filter. It’s

The old Naim Phono preamps cards are apparently the same circuit as the Stageline, and I found a circuit diagram of here:

http://www.neilmcbride.co.uk/mcboard.pdf

Might it be possible to tweak the circuit component values to make it roll off a bit little lower in the bass? - not massively, just a bit.

If anyone has any ideas which components to target it would be appreciated?

I thought maybe the uF value of series input/output caps could be raised, but 10uF in each position seems more than enough.

If the excessive high pass/bass roll off is built within the RIAA section it might be more challenging to address. I don’t have simulating software like LTspice etc. You need to take into account the neg feedback loops etc.

I know the Naim purists probably won’t like this idea, but it’s a decent phono stage with the right kind of cartridge and turntable, - if the bass extension could be improved just a bit I’d be quite happy with it using the Troika/Karma.

I’m not using it with other Naim equipment.

It’s a bit of a long shot, but if anyone has any ideas it would be much appreciated!

It doesn't have to be remote controlled . All I see on the bay are 4 input max. If you see the source of such board a pointer would be appreciated

Should the back of the bass driver(s) rest firmly on the internal bracing of the cabinet?

Are there any pros and cons of that in general and in my case?

In may case (slim 3-way) there are two stiff 5.5in high-excursion drives, on the same baffle (not opposing push-push). I have the option of placing some of the internal bracing on the back of the bass drivers. The drivers are 4kg each. The front baffle is 31mm, side walls 21mm, back wall 31mm. Heavy cabinet.

And what about the midrange?

I am a long time user of the VLC player, but for several years now it seems to be broken in some ways: it never launches cleanly, always warns of problems or asks for an update (which does not improves matters).
Here is an example (sometimes it is different):


Why can it not just simply work properly.
I think I am going to switch to a less problematic application: any suggestion?

Hi everyone,i have an Orion 225HCCA competition amp x-over and i don't know how i should use the bypass module,i need to run two 12" subwoofers at 2 or 1 ohms,is this the correct way to run it?thanks.

I got this power supply from eBay advertised as power up condition only and currently tried to restore it. Replaced some overheat resistors, rectifiers and power supply capacitor and neon bulb. Checked most of the components and tubes and replace some weak tubes. In general most of the components are still within the tolerance. Some exceeded slightly but I don't think it will cause much of the problem and did not replace them.

Attached is the output data after power it up. The main issue is it did not reach the max voltage except as noted in my file. Checked all resistors in the sampling network. They are fine. Negative 250V Bias is fine. I also checked out all parameters per Figure 4-2- Tube Voltage Chart on page 4-3 of the Maintenance section. The voltages are not really matched what specified there and don't know and not sure if they are really related to the issue that I have. One thing that's quite different from what specified in the chart is the pin 9 of V14 (6AU8). The chart said -61V on pin 9. It's measured about -61 voltage when Output Switch Position (0-500V) is in the "0" position only and I don't believe it's correct in other positions. My measurement on pin 9 started to turn to positive voltage when Output Switch Position (0-500V) dialed to position 100 to 500. On "500" position it measured about positive 289V. May be it's typo perhaps.

Appreciated any input on this. Thank you.

(Updated) (4-25-2025) 🌟💥All sold but, the gotham audio stuff. Still for sale.Good Morning. I should have done this with my first post. I will list the brand and meters or feet of wire. If you buy in bulk it get cheaper. I would like to see all of my wire gone and into go homes being used. I have the following wires for sale. All wire is unterminated and has no ends on them.

💥Please beware shipping has not been added to the price with the cables.🌟 I can split shipping cost if you buy in bulk or the cables are heavy. Thanks so much Jeff.


Wires that can be used for RCA Cables.

Sold /1. Gotham Audio . GAC 2111 10 meters. I paid $3.25 per. Meter. = $32.50. Am asking $22.00 for the cables.

Sold/2.Gotham Audio. Gac-4 ultra pro-1 4 metes plus 10 feet. I paid $21.25 per meter. =85 +15 = $100.00 my cost. Am asking $60.00 for the pair of these cables.

Sold/3. Mogmai 3082 50 feet at $1.20 a foot =$60.00 am asking $40.00 for this cable.

Sold/4. Mogami 2524 Wire at 24 feet $0.86 x 22 =$18.92. Am asking $12.00 for this cable.

Speaker wires.

Sold/1. Redco 12-2 C-2 12 x2 Gauge wire $1.25 x 50 feet= $62.50 I paid. Am asking $42.00 for this cable.

Sold / 2. Canare 4S6 4x20 gauge wires at $0.43 cents a foot a 40 feet =$17.20 . Am asking $10.00 for this cable.

Sold/ 3.Canare 4S8 4x16 gauge wires at $0.75 cents a foot at 25 feet $18.75. am asking $10.00 for this cable.

Sold/ 4. Canare 4S11 black color 4x11 11 Gauge wire 4S11 in black color is $1.44 at 28 feet=$40.32. Am asking $30.00 for this cable.

Sold/ 5. Canare 4S11 Grey color and 4x 11 gauge (ofc) in gray at $2.05 a foot at 24 feet $49.20 am asking $40.00 for this cable.

Mogami cables.

Sold/ 1. W3103 12 x2 gauge at 18 feet $2.86 =51.48 feet. Am asking $40.00 for his cable.

Sold/ 2. W3104 12 x 4 gauge at 24 feet $5.11=122.64. Asking $75.00 for the cables.

Sold/3. Mogami (o.f.c.) hook up wires 1 red 1 blue. I paid $60.00 dollars for both of them. Am asking $35.00 for the set. 50 feet each.

Other speaker cable brands for sale.

Sold/A..Whirlwind 4x12 cables at 26 feet $4.55=118.3. Am asking $88.00 for this cable.

Sold/B. CBI Power series 12x 2 cables at 22 feet $0.91 cents for $20.02. Am asking $12.00 for this cable.


Sold/🌟(Updated) Belden 1313A 10 gauge 10x2 speaker cables 54 feet $3.30 =$171.60.
Am asking $100.00 dollars. Buyer pays shipping. Thick heavy cables.


Sold/Audtek 13 gauge wire 13x2 at 24 feet $1.00=$24.00. Am asking $14.00 for this cable.

Sold/West wire I believe I bought a Redco a while ago. $0.45 cents a foot at 22 feet =$9.90. Am asking $5.00 for this cable.

Not sold yet. Gotham Speaker Cables.

1.(50010) SPK 2x1 30 Gauge wire at $2.45 a meter. 52 feet at 15.82 metersz . I paid $ 38.38 . Am asking $22.00 for this cable.


2.(50150) SPK-GAC 13 gauge shielded wire. $6.00 a meter. 38 feet of this wire. It’s 11.582 meters. I paid $69.49. Am asking $44.00 for this cable.



3.(50025). SPK- 2x2 13 gauge wire at $4.75 a meter. 42 feet of wire. Is 12.802 meters $ 60.00 my cost. Am asking $40.00 for this cable.

4.(50040) SPK 2x4 11 gauge wire at $6.96 a meter. I have 47 feet and 14.326 meters of this wire 14.326 x $6.96 = $99.27 my cost. Am asking $75.00 for this cable.

5.(5026) SPK 2x6 9 gauge wire at $8.95 a meter x 18 feet =5.486 meters $49.10 selling it for $42.00 for the cable. I also have a 28 feet of this cable as well = 8.5344 meters $76.38. Am asking $56.00. I will pay for shipping for these cables.

(Updated) 6.(50080) 2x8 8 gauge wire 8x2 at $16.30 a meter x 24 = $391.20. The heavest cable I have to sell. Come on a spool in a gotham Audio box. Am asking $340.00 and the shipping I will pay for.

Not sold/ A.C. Cables.

1. (85055) Gotham Audio GPC 3x5 4 meters x a meter $24.85 x 4 =$99.40. am asking $74.00 dollars and I will throw in an a second (85005 cable ) 10 feet I will give with buying the first cable.

Please E mail with questions on offers and shipping. Thanks for looking. Jeff

E mail. Jmboo1922@gmail.com

I have a silver Weiss 502MK2 for the coming Audio Show.

Tivoli Model One BT with bluetooth. All inputs are muted EXCEPT when using the Bluetooth input. Even the line aux input is muted which is on the same switch position as the bluetooth. On other switch positions, i.e. TUNER, can hear audio at very low level with ear up against the speaker, no audio from headphone jack either. Tuner is working because can see the Tuning LED light, and can see audio with a scope on the solder side of the 12 pin connector that goes to/from the volume/switch board. My guess is that the audio board has a solid state audio gate or switcher that won't release the mute when it needs to. Due to the audio board likely being multi-layer SMT, I am probably hosed!

I buy my dreaming(for 30 years) speakers DUNTECH Sovereign 2001 recently.
I had replaced original DA drivers with modern Scan-speak drivers .
Next step will be revising original passive crossover or jumping to active crossover???
Hoping that I can find the best answer here!
Thanks everyone!

Hi all!
I'm working with BT chips and small D-class amps!

3rd introduction attempt trying to get access to being able to post in the forum.

Ok, time to start a new build.

This time it will be on the larger side...

Stereo IB's with dual Beyma 21PW1400FE per manifold Beyma Speakers - Beyma 21PW1400Fe 21" subwoofer speaker - Beyma 21PW1400Fe high power 2,800 watt 21" woofer for all bass applications. Beyma 21PW1400Fe and other Beyma 18" speakers here.

Midbass with dual Beyma 15P80FeN in sealed enclosures Beyma Speakers - Beyma 15P80FeN speaker - Beyma 15P80Fe Water Resistant Speaker, 1,600 watt 15" woofer for all mid-bass applications. Beyma 15P80FeN and other Beyma 15" speakers here. Great for indoor or outdoor use.

Midrange with dual Jantzen JA-8008 HMQ http://www.jantzen-audio.com/wp-content/uploads/2013/06/JA-8008-HMQ.pdf

The higher frequencies will be taken care of a Beyma TPL-150B https://www.beyma.com/speakers/Fichas_Tecnicas/beyma-speakers-data-sheet-amt-TPL150B.pdf

IB's are already up and running since a couple of years.

Midbass enclosures will be sealed (not ready yet) around 40L net volume per woofer, 2 per side. Expected to be crossed 80 - 300 Hz.

Midrange enclosures will also be built sealed with a volume of about 15L per box. 1 driver per box. 2 per side. 300 - 2000 Hz.

TPL-150B with open back into sealed stuffed cavity modification from 2000Hz.

It will be a IBWWMTM...? 🙂

This will be an active 4-way system with Minidsp OpenDRC-DA8🙂confused🙂 and Crown XLS amps for the woofers and Firstwatt M2's for the mids and tweeters. Expecting 100dB+ sensitivity.
I'm a total noob when it comes to Minidsp so this will take some time to learn. Done some studies already and it does seem quite easy to get started anyway. Time will tell.

If somebody has a better suggestion than the OpenDRC-DA8 for X-over and DSP duty, please do tell. We have no secrets...

/Z

I am here to troubleshoot a Tivoli Model One looking for those who have experience with this radio.

Anybody have a schematic for this amplifier?

papaZBill can you help?

One of my headphone cable models 'The Crystal Cranium v2.0' has a cable geometry consisting of 4 hand-braided (by me) strands of 4-core pre-braided (by supplier) cable.
Subsequently it has a pretty chunky overall outside diameter and for a cable needing a 4.4mm balanced source connection it requires a Pentaconn connector with sufficient internal diameter and rear aperture to accommodate the cable.
My regular Aliexpress supplier has disappeared without trace. It took obtaining sample connectors from about 30 different suppliers until I found him and the really decent connectors he was selling. Nobody else there or on alibaba, bang etc was selling these things, so I had to start the whole process again - sourcing a decent connector from a 'reliable' source.

I found a couple of suppliers recently with in-spec connectors. One has an 8mm OD aperture and the other a 7mm aperture. Both seem good quality, well-machined and smooth barrel threads, good quality barrel paint and both have decals. Both are also gold plated and not just painted and measure about the same for capacitance.

Slightly different designs but at least I have 2 viable candidates for wide-body Pentaconn connector supply.
However, I can't help feeling that aliexpress sellers are jumping on the 'posh packaging' trend and bumping up prices accordingly. There was a time when you could pick up a box of baggied connectors like these for not much money, but these days they come in fancy packaging in multiples of 2 or 4 with a hefty price-tag.
Any other MOT's noticing this trend?
Somewhat irritating when you try to keep your own prices consistent and stable. :/






It's almost a bit of a shame that I seal the connectors to the cable using glue heatshrink but it makes them very strong and prevents the terminations from oxidising.

so Graphene is both the strongest and most conductive material known

orders of magnitude beyond Aluminum

doesn't that make it ideal material to make true ribbons of ?

and could such a ribbon actually become viable in prosound ?

i am also thinking you could laminate graphene on titanium foil.

titanium is proven as diaphragm material but not very conductive.

Starting this May 2 the minimum processing customs fee for a package from China into the USA will be $25. That's on top of the new tariff being added. Processing fee goes to $50 in June. Gone will be the days of 5 100mm x 100mm PCBs from JLCPCB for well under $10 delivered to your door.

I have a Hafler HA15 in pristine condition. Unfortunately, it doesn't work. If you have the skills to fix it, I will gift it to you for free, you pay shipping. I have the circuit diagram from the manufacturer but they said they can't help. If you want this piece, let me know, but I would like an assurance that you actually have the chops to repair it.

The first point release in V9. Enough bug fixes since V9.0.0 that it is safe for novices to try.
https://www.kicad.org/blog/2025/03/KiCad-9.0.1-Release/

I'm just thinking about improving my loudspeakers: Braun LS200. I'm curious if the drivers' positions on the speaker baffles were rearranged to follow D'Appolito's MTM layout. Is it absolutely considered an upgrade? I mean, is there any obvious improvement?

Here's a beautiful image of the LS200 from its brochure.



My idea for converting them to MTM style is shown below.

A thread on this topic could be an inspiration for newbees & interested folks

Here some ideas I realized:

glued in egg crates (the real ones) and using a thin sheet of damping. Thats for being localized more in the middle of the box where it is damping lower frequencies than only being positioned on the walls

reflex port in the corner of one wall as a cutout and port made of cardboard sheets glued in. Easy to realize bigger port diameters like this.

piezo tweeter on the side for indirect high frequency dispersion but it can be put on and off to taste

Hammond H1 Tube Amplifiers - for Parts

Hammond H1 and H1B Tube Amplifiers - for Parts.

Bought these two amps years ago to restore, and lost interest...been sitting in basement ever since.

I believe all transformers / chokes to be functional. I think one of them is in operating condition.

How's $150?

These two amps are heavy and would prefer local pickup - west Sub of Chicago...

Pics forthcoming...

Thinking of keeping one for a guitar amp...