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WTB-Scanspeak 10F 4424

Hello!
I need a pair of them, Please let me know if you a pair, to spare!
Condition-Fully functional and physical is great condition.

The Audax PR240Z0 woofer looks strange cause the impedance plot in the datasheet shows a negative impedance plot from 50-1,500hz?

Am I reading it wrong?

Hi,
Just assembled the cabinet below to mount my Dynaudio 24w100 driver.

Dimensions are: 30" tall, 10.5" wide, 14.5" deep. Volume=52 lts


Need advice on the following:

1) Tweeter
2) Ported or not
3) Crossover diagram

I would prefer to keep it as a 2-way design

I’m looking to build a speaker with the maop 11. I have a cabinet builder ready to build whatever cabinet I want. what I am looking for is the best overall sound. I’m not necessarily worried about bass output as I can add subs. Bookshelf or floor standard, either one is fine. so, if I have a box that can do reasonable bass output as well, that’s fantastic, but if I’m just looking for overall clarity/sound stage, not necessarily worried about low bass, what would you all recommend? If you have a recommendation, please also include a link to the box plan you recommend. I appreciate any help upfront. I am new to the DIY process.

I’ve been getting this distortion sound for a few weeks, I’ve tried different connections, speakers, settings, and all has failed. Below is an example of the issue. Thanks!

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printed circuits for the realization of the Hiraga le monstre amplifier, designed for assembly with modern transistors that are easy to find
https://www.ebay.it/itm/363885006897

I'm looking for a good sounding, reasonably priced 10" or 12" woofer to be used in a 2 way with Michael Chua's recommended Pyle PDS442/Dayton H07E compression driver combo on top. I will be using 6BQ5 tube amplification.
Thanks for any and all suggestions.

For sale.

All needs to go.

1. MiniDSP Dirac Live box

Both DDRC-22D
and DDRC-22DA in 1 box.

Dirac Live® correction DSP with SPDIF/AES-EBU/Toslink interface inputs.

User serviceable outputs (analog or digital)

https://www.minidsp.com/products/dirac-series/product-line-summary





I’ll include both output interfaces so you can choose: digital output or analog output. Just needs removal of a couple of screws and disconnecting/connecting the desired output interface, so that it can be converted to analog outputs. Or digital outputs.

Currently in digital out mode; for connection to external DAC.

But I can convert it into a DAC for you:
https://www.minidsp.com/images/documents/Product Brief-DDRC-22DA.pdf



I can confirm it works, as I’ve used both the analog out, and digital out version.

price lowered

$450 USD



2. miniDSP nanoDigi DSP

SOLD

Asking $250 USD

3. FOUR FiiO D03K stereo
(8 channels of D/A conversion)
SOLD
$80USD

4.MiniDSP 2x4 HD
SOLD

5.https://www.minidsp.com/products/accessories/wi-dg
SOLD
$40 USD

Shipping ex-Australia.
Paywize or PayPal (you pay extra 3%)

Edit: found more stuff to sell
Edit 2: … thanks for your interest: photos and prices added.
Edit 3: prefer to sell nanoDIGI and DACs together. Please make offer.
Edit 4: another price drop and condensed for things sold and shipped.
Edit 5: REMOVED photos of ALL items no longer for sale.

Sold!


Time to admit I have more stuff than I have space for, or time to build.

Up for sale is an almost fully populated cathode coupled line stage kit by Mr. Broskie. These are currently out of stock on his website. I was setting it up for 12 volt tubes, then ended up building the NuTube preamplifer instead. Don't need this anymore.

I have $250 in receipts for everything seen below.

I let the smoke out of the PS-18 board with a slip. Itll arrive with spare parts, and everything it shipped with.

The CCA will also arrive with everything it shipped with, which is every option you can check on Broskie's website when buying one.

Antek AS-1T200 also included.

$150 + shipping to the lower 48 only please. No, I won't go lower.

Hey 🙂
I have a studio and I am looking at branching into Atmos. I have a pair of Barefoot MM27s and was looking to diy some 2 ways to pair up with it within a reasonable budget.
If anyone has any input on some driver combinations im fully open to suggestions. Thank you!

I purchased a 10 years after version of Mesmerize when it was released.
If I were being picky, I would ask for 4 matched 2SK170 B grade, plus 6 not matched 2SK170 or LSK170 B grade. Let me know what you have.
I have plenty of old radio stuff to trade, tubes, transformers, BTC, other.

when i probe the output of this regulator, i get a 5mVp-p wavy response, as if the scope probe is not connected.
i was expecting a straight line, maybe a tiny amount of noise.
load is around 10mA, input 58V, output set for 48V.
(cct is from a JLH power amp supply cira 1984)

I have recently purchased a larger QSC system that came with a set of QSC's MD-S218 cabinets for subs. Nice sub...but no handles, and sized entirely wrong for packing in the truck, and I bet I need more cabinets to run the system outdoors anyway. My initial though was to swap the MD-S218 cabinets for GP218 cabinets, but I haven't found any used GP218's for sale anywhere, at least not enough of them that I can get shipped here. I'm beginning to wonder about the possibility of making a clone/substitute of the GP218 with my CNC machine & how to get the box design & driver choice correct to play well with the rest of the system.

Anyone tackled a project like that before? Tips? Thoughts? Suggestions? Anyone know if the MD cabinet is the same driver as the GP218?

Thanks,
Todd

Hi finally got my M&K KX10BK SubWoofer fixed of sorts, sounds great again no thanks to the hours of messing about with fake transistor, the only problem I have now is how does the circuit mute the speaker as I get a nice thump every time days gone by a relay was used, I have noticed with no speaker connected the DC offset which ideally should be 0 Volt but Its about .235 volt there is no means to adjust this with an offset preset, it appears it may be that I need all match pairs of transistors but I struggled enough getting non fake ones as I was.
I just wondered if anyone else had similar problems.

I found a pair of these for sale. Dirty, corroded, and untested, the seller wants $4000 for the pair.

In addition to cleaning, it would need re-capping, new sockets(?), new tubes,... All of which I can do myself.

Are transformer failures very common with these? Any other concerns with this model?

It looks like clean, known working units sell for $4k/pr, maybe $5k/pr if they've been rebuilt/serviced.

What would be a reasonable offer given the condition and untested?

We are in the process of closing our business due to retirement. We are no longer accepting any new service work and apologize for the inconvenience. All shop test equipment, tech benches, parts, and upgrade procedures (intellectual property) will be sold. Please inquire by pm if interested.

Rick

I have a Son of Ampzilla that I acquired in 2014. I got great help on this forum back then for a channel drop problem. The amp has been working great until recently.

I now get a pretty severe turn on pulse, followed by a slight hum that is of equal volume in both channels. The hum is more pronounced with the inputs disconnected. The turn on pulse is the same if the inputs are connected or disconnected. The pulse has been getting worse and I am starting to be concerned for my speakers. The amp still appear to work fine as far as the sound goes.

I am thinking something is getting funky in the power supply since both channels are equally affected. Anyone run into this issue before?

Search on marktplaats point nl voor boominator.
This boominator is build by the guys from Accusafe in Holland
Is has never seen a festival and I think less then 25 playing hours
So basicly it is as good as new

Up for grabs is a Kustom Profile Series 1 P.A.
100W (50W per Channel)
5 Total Input Channels for Mic/Instruments
One Playback Channel w/ RCA In
One Recording Channel w/ RCA out
Two KPS-LS100T Gig Monitors (no stands)
Two 10ft 1/4" Monitor Cables
Asking $200 or best offer.
Will ship to Domestic US for additional fee (UPS estimate is $80)
Each component of the system weighs 15.8 lbs with an approximate shipping weight of 50 lbs. Local pickup available in Southwest-Central Oklahoma to nix shipping costs.
System has been tested, and performs very well.

Up for collection only and from Milton Keynes is my Aleph 3 clone .

In excellent cosmetic condition and perfect working order.

I’m looking for what I paid for it which was £650 ( for established members )
I may also consider a swap for a quality preamp but it must have remote control.

It has a ding on the very back right hand cooling fin ( not me )

Please message me if interested

It’s a beast of an amp so you may struggle to fit it in a Hifi rack .

30w class A

Built by Joe Henry

Dimensions
50cm Wide
40cm Deep
22cm High

Speaker protection
Dual toroidal transformers
Dual 50 amp bridge rectifiers
Dual power supplies
160,000uf Elna capacitors
Double-sided thick gilded PCB boards
Power Soft start circuit
Blue LED on/off switch
Input differential Transistors using the new US FU9210
DC blocker
Precise matching mosfets
Supply rail fusing
XLR balanced inputs
RCA inputs
Audio grade binding posts

SPECIFICATIONS
Gain 20 dB
Freq. Response - 0.5 dB at 2 Hz, 100 KHz
Power Output 30 watts/ch 8 ohms
60 watts/ch 4 ohms
60 watts/ch 2 ohms
Maximum Output 23 volts, 8 amps
Distortion (1KHz) 0.2% @ 30 watts, 8 ohms
1% @ 60 watts, 4 ohms
1% @ 60 watts, 2 ohms
Input Impedance 23 Kohm
Damping factor 100
Crosstalk > -80 dB 20-20 KHz

Hello all,
I was just wondering on "settling time after switch-on" of DC blocking capacitors of preamplifiers. Some designs have say 1uf , some 10uf and some have electrolyte 220uf or 470uf. Perhaps in case of 470uf we would have longer settling time. Is using 470uf ok? Or we would face a problem? And if the answer is yes what would be the problem of long settling time? (Although some famous designs use large value bi-polar capacitors. )
Thanks.

Folks,

I was wondering if anybody has a copy (PDF preferably) of the SAE 8000 Tuner schematics. I am trying to repair the LED issue and to replace some components to make it more palatable to modern high-end standards.

Thanks in advance.

Yves

I Build one amplifier using 2sa1943 and 2sc5200 transistors 200 watt . I have 10inch 4ohm 150watt woofer which is working fine now i am planning to install twitter in it so should I install it with passive 2 way crossover or just connect it parallelly ?

I almost completed a single ended KT88 amp. It worked fine, but I did not finish it because it weighs 30kg. I put all high voltage tube amps high up on a shelf to keep them away from children. The shelf is only rated for 30kg so I can't put it up there. Even if I wanted to put it up there I don't have the strength to safely lift it that high. So the amp is just sitting there and I can't use it. The only options is to build a cage around it or to split it into 2 chassis. I am choosing the later.

It is definitely not ideal, but occasionally I read some of you do this. What do you use for the connection between them. The easiest option I came across is the MC4 connectors meant for solar panel. They are rated from 1500V DC 30A. I wonder if anyone have experience using them?

My other option is to use octal CMC type tube socket (the bottom can be plugged into any tube socket) which would require a bit more work. My other other option is to make both sides unremovable without opening up the chassis,

On tne commercial side, I see manufacturers use aerospace connectors for this. The highest rating I found are at 600V. Not unusable, but I would prefer the rating to be 800V or higher.

Finished these speakers tonight and thought I’d share the grills since I haven’t seen this done before.

Used #10 spax screws because they have a large flat top to mate up with the neo magnets I got from Amazon (1/2” x 3mm). Black magnets to hide better.



Bonus tip: put some blue painters tape under your driver mounting area and it will come back out easily in the future. Did this under the WG as well.

I started with the design, the back of the preamplifier, now it won't necessarily stay like that, if you have other mounting options, they are welcome,,,,,,,

1. 4 inputs by selecting CD, TAPE, RADIO, etc

2. A direct entry

3. A balanced XLR input

4. and two exits

http://www.vaneijndhoven.net/jos/relaixedpassive/

Hi,

We use to replace the orange LN capacitors by Low Leakage caps, such as Nichicon KL for example.

But sometimes we find YELLOW capacitors, like this Nichicon :



What are the specificities of these yallow caps, and what would be the best replacement ?

Thank you

I am going through the process of getting/finding my first adjustable and current limiting power supply. I have a linear fixed regulated 13Vdc supply and some SMPS blocks (18V etc) but I'm finding testing circuit ideas difficult without some controllable power (other than a lightbulb). I have a scope already so it's time to add a current limiting power supply at the cheaper end of the scale.

My requirements are simple - control at low power before moving up. To that end my requirements are:

• Small - it needs to sit on a shelf next to the little DSO.
• 1-60Vdc allows me to test low voltage including
• floating power - this allows me to use a virtual ground as ±30 or ground as +60V or -60V.
• Output enable/disable switch
• Separate current and voltage dials.

Bonus points

• programmable power
• additional power ports
• USB SCPI port

I've actually now ordered two and received one already. The reason for this is that the Multicomp can only limit down to 250mA and that registered after it had shipped. I get the second tomorrow after which I will (highly likely) RMA the Multicomp Pro. However this gives a great opportunity todo some research with device in hand and pass on that knowledge for any other beginners. My money so this is not sponsored.

The supplies are:

• Multicomp Pro MP710081 (a rebadged Manson NTP-6561)
• Tenma 72-8340A

Hi

I have a few questions regarding the placement of a driver in a front-loaded horn.

In horn resp, it sims it as the driver firing directly into the mouth of the horn i have attached an example pic.

However I often see in front-loaded horns that the driver is placed on the side of the horn and fires into the side/throat I assume this is in order to fit the driver in a reasonably sized box (WSX Plans attached as an example, as the plans show the driver shoots into the side of the horn and has a slight gap which I assume is based on compression ratio. Does the throat make it as if the driver is shooting directly into the horn, if so what is the best way to design this so it works as expected?

I'm wondering if anyone has any advice/knowledge on how best to do this without affecting the response of the horn.

Hope this makes sense.

I am fairly new to horn/cabinet design so any help or advice is appreciated.

TIA
Ollie

Decided I need to clear some projects and unfortunately this one made the short list of one's to sell. Hopefully it can give someone some pleasure and not be sat in a box.

Nearly completed in that both channels nearly fully populated. All components are there I believe apart from the self wind output inductors. Also may need fuses. Not sure the ones I have are correct
KOA BPR, Yageo MFR, Elna Silmic , Vishay in the build.

One heatsink is drilled and tapped. Will include ceramic insulators.

Asking £100

Howdy folks. Forgive me if this is an absurd line of reasoning, but I have a question regarding the manner in which sound travels in a horn / waveguide speaker. I have been watching a bunch of YouTube videos from Joseph Crowe, as well as reading some of his blog posts, and I have noticed that he pays a great deal of attention to how the sound travels along the horn even after it wraps around to the other side of it. This is obvious just by looking at his designs, which I have attached. At this time I do not understand the math involved with the shapes he comes up with, but I do know the shape of the back of the horn is just a continuation of the formula that dictates the shape of the front of the horn, which if followed further seems to start to spiral?

Mr. Crowe seems interested in minimizing diffraction, as well as deadening the sound that makes it to the backside of the horn (back waves?). In the picture featuring his cat you can see that he has put acoustic dampening into the concavity in the back of the horn, which is meant to attenuate the sound energy.

Mr. Crowe seems to think this rear radiation is substantial enough to warrant this sort of design, and I am wondering if you could take this in a different direction.

If you had the mathematical know how, could you hypothetically guide this backward travelling sound energy into a shape that disperses the sound in a manner that mimics the sound of a dipole or bipole speaker? I know the time alignment would be different, but just considering the listener's perception, I am wondering if something pleasing to the ear could be achieved. Sort of an "ambient tweeter" effect, like in the Smell E/III

I am new to audio, and very ignorant to the math behind speaker design, so forgive me if this is an obviously dumb idea. Thank you!

On the TLS.org site for calculating component values of 2nd order pllxo, the formula prescribes that C1 and C2 as well as R1 and R2 differ by a factor of 10. What is important about that factor? There are myriad combinations of values of those four components that will give a specific identical (or very nearly so) F3. Why is it defined that the two sections differ by a value of 10? What happens if C1 and C2 (and proportionately, R1 and R2) differ by a value of, say, 8?

Thanks to anyone who can shed light on this.

Peace,
Tom E

Hello there. I want to replace the rubber grommets on my Rek-O-Kuts but I'm a little intimidated by the complexity of the mechanism. Is anyone aware of any helpful instructions anywhere on how to get this apart and back together again?

I'm looking around for what's a good speaker that'll work well in a sealed box such as the LS3/5A spec box. Falcon acoustics have recommend a SPH-135TC as they say it works well in a small sealed cabinet but have none in stock. I have also seen a SPH-135AD anyone compared those two drivers sonically?

Obviously I've heard the B110 in the LS3/5A and its a great combination of organic and richness. These are such old drivers though surely things have improved and it would be nice to have something which betters it for less money as the retail of those now are very high.

Something warm colourful and detailed sounding would be nice.

Another one a DIY forum member mentioned was the Peerless Heritage 5 1/4" woofer: Peerless TPY05W08O0088 5-1/4" Heritage Family Woofer 8 Ohm. Cant seem to find any in the UK though would have to import that one. Those old clear ProAc drivers are not available anymore by any chance are they the Seas type? And would they work in a small sealed box?

I've actually got two builds on the go I may get the cheaper Monacor for one and maybe splash out a little more on something a little more upmarket for the other, any suggestions welcome and greatly appreciated.

Hi guys working on a T2500-1bdcp had 1 bad power supply fet. I have that clipped out and amp powers on but no output. Checked the class d regulators and was not getting and positive voltage so checked the positive regulator pin 2 and was getting 4 vdc. So I removed the bd card and my class d regulators are getting voltage. Checked for shorts on bd card but didn't find any. Any ideas?

I tried installing W8-1772 for BH in TQWT, but it lacked bass due to the rightward frequensy response.
W8-1808 or W8-2145 seems to be more compatible.

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Howdy folks. I have asked a similar question here before, but I am justifying in my mind asking this all the same because I think the responses I will get will be quite different than my last question ("What mistakes did you make as a beginner?"). Anyways, this is all in good fun so I hope y'all don't mind.

My question is: how much did you know about speaker design at the time that you built your first speaker? How did it turn out?

I'm prompted to ask this because I want to do my due diligence before committing to building a speaker, but the more research I do on speaker design, the further I seem to get from being ready to make anything worth a damn.

I know I'll never know all the theory there is here to know, but when do you know when it's time to drop your cookbooks and design guides and start playing with power tools and caps and inductors and such? I hear nothing beats experience, but experience is expensive! Ya know?

Excited to hear responses, and I think it would be very cool if anyone included pictures of their first designs!

-Bryguy


EDIT: I should mention, I truly am more interested in hearing about your experiences than I am about collecting your advice. I have decided to build an established design before doing anything else. Hopefully that will make me more comfortable with committing to a design of my own

I know, I know, probably a dumb question. But.

LPs are overwhelmingly played with a 9" pivoted arm, why not cut them using the same geometry? If nothing else it would make playback alignment much simpler and accurate.

Listed for sale are two Alpha-Core Inc copper foil inductors (AWG 12, .47 mH). They were bought from Madisound some years ago for a crossover design, which needed a different inductance at the end. These were used in testing only.
Asking price is $30 each. Buyer to pay exact shipping cost.
Please PM if interested. Thank You.

I have two Unused Angela Polypropylene Caps for sale. They are rated at 47.00 uf (+/-5%), 630VDC.
According to the label they were made in France (in '98?). Dimensions: 1.9" (D) x 2.8 (L).
Asking price is $40 for the pair. Buyer to pay exact shipping.
Please PM if interested. Thanks.

Just putting my toe in the Mark Audio water with some CHN50s. Looking for design ideas. Has anyone done a Cheap Trick 193 style cabinet with these? TIA.

Two Hammond 158M inductors (10 H , 100 ma ) for sale.

Bought these for a tube amp project which never got off the ground. Unused in original boxes.

Asking price $20 each. Buyer to pay exact shipping costs.

Please PM if interested. Thanks!

I have a Magnetek filament transformer (F-6X, 117v Primary, 2.5v CT Secondary @ 6 amp) for sale.

It is NOS, unused and boxed. I bought it for a tube amp project but never got to work on it.

Asking price is $15.00, Buyer to pay exact shipping cost.

Thanks for looking. Please PM if interested/

Please let me know, if anyone before me , made or even proposed such idea. Here it is:
Instead of making a box for a sub, why not take 3 or 4 Aluminum Wheel Rims, like this: https://www.amazon.com/Enkei-RAIJIN...&sprefix=wheel+rim+japan+racin,aps,206&sr=8-6

stack em on each other, connect them together with five titanium rods in these wholes in the middle of the rim.........and voila!
We have the Beast. 18 inch woofer can sit on top of such DIY -ultra-sophisticated, hand-made, painstakingly manufactured by artisanal passionate engineers, blah blah work of art!

We can damp the whole thing inside using alpaca wool bags of salt or expanded polystyrene - very lightweight.

What will be the weak sides of such construction? Aside from WAF and industrial vibe? But can be veneered, hm?

Hi guys, I have acquired 2 nearly new panels from a Martin Logan Quest with both 12" woofers and power supplies and I was planning on making my own woofer enclosures and frames. I was planning on building a passive crossover for the ESL panel using the original schematics and then using one or more pro audio DSP amps for the woofers depending on the orientation. I currently have a set of Aeries I speakers that are powered this way and the results have been fantastic. I see the newer models use a pair of woofers per speaker in a push-push configuration with DSP on the rear firing woofer.

I am wondering if I should design these with rear firing woofers as well? Since the bass sections will be ran in an active configuration I'm not really tied to using the original woofers, I would likely stay with sealed boxes for the sake of simplicity. I am asking this question because I am new to speaker building outside of some sealed and ported subwoofers I have made in the past and I don't want to go down a path that makes these very difficult to design/integrate. I am very good at mechanical design and fabrication as that's part of what I do for a living, but not so much speaker design.

I have only just started design work so I am not really tied to any one configuration. Any advise is much appreciated!

Testing to see what value of a Screen resistor works the best...

Bought today. Pristine condition/function , just didn't have a cartridge or stylus.

No idea if there is a 3rd party/new etc cart that will fit it but I'm totally open to that too. Just no idea where to source them.

Any info much appreciated!

Thank y'all so much

When I power this amplifier up for the first time I see no oscillation on the outputs but there seem to be a weak signal there.When I disconnect and reconnect remote voltage it will start oscillating and plays good audio.If I let it sit for a while it behaves they same way.

Any suggestions?

Hi all. I have just purchased a Vevor 3 axis laser and cnc machine. Can this be used for making PCBs?

Thanks and regards
Randy

Hello people,
just for completeness I decided to post other measurements of the output impedance in the circuit configurations dear to me from a strictly sonic point of view .... plus a few other considerations ....
Obviously, as usual, participation in the discussion would be welcome ... as long as it arouses interest in your minds
Happy reading to all of you!

Long time lurker here poking thru hundreds of posts and still looking to connect some dots, any help would be appreciated.
I run a simple 6V6 driven SET ~2W) tied a sub 90dB efficiency speak (ported) that sounds very articulate and pleasing, but now looking to build high impedance matching speaker for a small computer room. Those speakers will go back to being driven by a PP amp that seems to be better matched at higher volumes in the room that it is in.

The new situation would be somewhat of a close coupled listening (not a perfect room at all) and would need to target a smaller sized cabinet. I realize most of the legacy drivers impedance curves did match well for high impedance amps, but now wondering if any of the recent gen drivers fill this bill? Much of the work on the earlier drivers/cab's seem to be obsolete and the newer drivers dont seem to be developed much with the older speaker designs, at least not in depth.
The min- Onken or FHL or would be nice if possible and MA drivers?
Thank you in advance!

Nice example in very good condition. Backed by a great customer support from Rogue in a case of troubles. $750 plus around 60+ LBs shipping from 48212
No chance building anything comparable for the price. Good parts and a decent platform to experiment with upgrades if desired. I can meet within 100 miles radius from home.

Hello all,

First post, long time lurker. I've been building for about 12 years with varying amounts of success. I started out with trying the different types of enclosures from sealed/ported to some quarterwave and OB stuff. Then I found out about miniDSP and fell down the active rabbit hole for like 7 years. Here are some pictures of one of my builds. Recently the GR Research youtube channel got me interested in actual passive crossover design and measurements and that's pretty much where I am now. I converted some of my active builds to passive using measurements and software for the first time. Then did some other upgrades to speakers for some friends.

Recently I decided I would try to make a small bookshelf speaker that could come-to-market as an exercise, not an actual goal. This being my first post and all, I want to stress that I'm fully aware a speaker I'm making isn't going to show up in stores, ever. I'm not even trying to sell this pair, I'm giving them to my cousin. Anyway, here was my attempt at making a cheap (sub $1000 MSRP), small, bookshelf speaker. The project kind of snowballed and ended up not being very cheap after getting the MDF CNC'd on the second attempt and adding a second passive radiator. The drivers are the SB Acoustics SB13PFC25R-08 5" Paper Cone Woofer and the SB29RDNC-C000-4 Neo Magnet, Ring Dome Tweeter.

I used .5" MDF on the prototype and a single passive radiator (rear mounted). The bass wasn't very extended and the cabinet had a good bit of vibration on the sides, despite having a brace between the tweeter and woofer that touched 4 walls.

I moved to .75" MDF and two passive radiators to hopefully boost the low end a little bit (I'm guessing this sounds funny to better designers). I didn't succeed with the bass extension in the end. When selecting the woofers I wasn't sure if I should trust the low frequency part of the plot, but after completion I believe I have my answer.

The front baffle is 3D printed and bonded to the MDF with resin. Printing allowed way more freedom in angles and features since I'm not very good at woodworking. They were printed at 25% infill and weigh just under 500g each. On a small build like this, I would definitely 3D print again.

How do they sound? I was very surprised at how detailed and accurate these things turned out. These $35 woofers are an insane value and I will definitely be using more SB Acoustics drivers in future builds as a result. I really enjoy the tight bass that they are able to produce. They only reach down to 60Hz, but there is noticeable drop-off below 100Hz. Bass strings are very articulate. They are fun to listen to after a healthy bit of bass boost on the amplifier side. Imaging and transparency are very good. I really like the sound of this tweeter and it's small faceplate.

Specs:
60-20,000Hz +-2.5dB
~91dB efficiency (this seemed high to me, and I haven't measured this before so I may have done it wrong. I used my o-scope to set Vrms to 2.83v at 1000Hz and did a sweep at that level)
8ohm nominal, 5.3ohm minimum
Internal volume: 9L
External dimensions: 8" wide, 11.25" tall, 11" deep

Material costs:
Drivers: 71.60x2 + 34.70x2 + 35.70x4 = $355
Crossovers: $111
3D Print material: $15
MDF: $25 (can be cut from 1 quarter sheet)
Total: $506

Takeaways:

• They are a good speaker, probably my best so far in terms of natural sound. BUT, I'm not sure anyone would want it in the $1000 range without more bass extension.
• It's hard to make a cheap speakers without auditioning a bunch of drivers and prototyping a lot of enclosures.
• Passive radiators sound really good but add a large percentage of cost, duh.
• It's even harder to make a cheap speaker when they have to look good. These look OK in the pictures, but could not be sold in mass market they way they are.

Hello everyone!
I have been given a Laney RBW300 to check (I'm not a professional but I have electronics as a passion e built some amps, mainly tubes).

The amp was recently used during a concert, I was not present but the issue was described as a temporary swing in volume (getting low then back up etc).
When I've received the amp it had the MV knob at 10.
I've turned it on and before connecting a bass it was making at "midrange sound".
Then after connecting the bass (and lowering the volume to human levels) that sound disappeared and now it doesn't do it even without any instrument connected and volume at max.

That's it I was unable to reproduce the problem, but I've just played for 20 minutes or so (the amp was used much longer during the concert).

Now, I've found this vid
Login to view embedded media
So I'll clean all jacks and pots but I was wondering:
Can this (up and downs of volume) be caused by old electrolyct caps too? Not able to keep the powersupply voltage during long sessions at max volume?

Thanks

Hi, while waiting to rebuild my area to play with circuits, looking for simple circuits I came out with this:



The driver is a 12AT7 in shunt cascode mode, whilst the power amp is a KT88 with 23% UL and 25% UNSET.
They are DC coupled because the bias of the output tube is set by the trimmer U5.

Most probably it is not the best working point, as at 1 Wrms it already has 0.8% 2nd harmonic (while all others are at least 32 dB lower):

but it keeps the 2nd dominant until and above the 21.5 Wrms at 5% THD:

and has a Rout of 1.36 Ohm without using any feedback.

A question for @Tubelab_com : can I double the FQPF9P25 having a parallel source follower to share the 18W to be dissipated?
I will have twice the input capacitance, but it will handle the power in a safer way.
I will of course try also the suggested 10% a-g1 local feedback, because in SE there's no issue with high g2 voltages as I have in the PP designs.

Hi all,

I've just finished a build of a 4 scoop, 5 way dub sound system. I have a DSP and amplifiers and would like to eventually get a dub/reggae preamp down the line when I have the funds.
My question is how do you get the benefits of a preamp and the DSP at the same time?

The preamp has many functions I really like but I also want to use the functions of the DSP such as time align and limiting etc.

Does one cancel out the other or can they both be used in unison?

Many thanks!

I'm putting together the cases for my p3a and p88 amp and preamp and was wondering what people do to put lettering on the front panel. Normally on store bought equipment all the lettering is silk screen printed but obviously that's not possible for 99% of diy'rs. What are people doing or are they just leaving the panels unprinted.

Having reently been asked to repair one of these Professional HiFi Amplifiers with a defective mains on/off switch (one pole totally o/c), which I've now replaced, I found that the BR82 bridge rectifier was s/c across 3 of it's 4 terminals-this in turn had caused the 5A(T)fuses in series with the transformer secondary to blow. I've now obtained a replacement rectifier and 20mm ceramic fuses of the correct type, and checked the secondary voltage on the transformer, which is 28-0-28vac, measured with my DMM. This would give nominally 40-0-40vDC, which, to, me is about right. As there do not appear to be any other faults, I'm wondering what caused the rectifier to fail in this way. On another forum someone suggested that the faulty on/off switch may have caused this to happen, but, despite almost 50 years of working with electronics, I cannot see how an open circuit connection between one side of the mains supply and the transformer primary could possibly do this, since, surely, no current can flow in any circuit unless both sides are connected? If I'm wrong, someone please enlighten me!!

Here it is, a piece of DIY history. To my knowledge, this was the only one produced. Specs are attached. It can come with this extremely sturdy box (1.5" thick MDF) if you would like. I think the box is a bit oversized. I bought it from a local car audio blogger who had it in his house. The only way to ship the box would be freight, and I don't think it would be cheap. Otherwise I'll dismount the driver and try to figure out how to get a crate it will fit in. I'd love if you were local to Tampa, or could pick it up because shipping this is going to be complicated. I'm going to put a $1000 price on it. I'm not sure if that's more or less than it's worth, but it's a unicorn. Shipping will be at cost, but like I said, I'd prefer someone who could pick it up. I was powering it with a Behringer EP2500 which is also for sale.

Hi

Not much time left but nice pair of 5K, 10W, Transcendar.

By rare, I mean that you don’t see that brand too often on eBay

https://www.ebay.ca/itm/165586974300

Eric

Hi All,

Is the Zen Ver8 suitable for a headphone amplifier?

I've seen that someone already did a similar circuit a while back.

I only need 1W max to drive some 32ohm headphones.

Thanks

For sale as per thread title at £60 for both items with UK delivery.

Happy to deliver within 30 miles of Gainsborough North Lincs.

Having bimbled around with other possibilities I'm coming back to building a pair of compact WAWs with a pair of Alpair 5.3 full-ranges and a pair of scanspeak 15W/8530k01 drivers.

I'm quite new to full-range drivers, so out of my comfort zone using such tiny speakers as the 5.3s covering a wide range (I was somewhat with Troels Gravesen on liking reasonably sized mid-ranges in conventional 3-ways). They have a relatively large frame/border, but the alpair 5.3's actual cone is noticeably less than 2.5" diameter, and the soft rubber bits don't take them much over, though they've sometimes been categorised as 3" on this forum, as probably befits their real-world capability.

That said, I'm sure it'll be fine; massively high SPLs aren't needed as the speakers will be situated close up (on a desk). Also, the 15Ws are properly good performers in their own right and will also go quite high if needed; well up into conventional 2-way XO territory if so wished (though that isn't the intention). So great flexibility of XO-point according to taste.

On the low end, it seems the 15Ws do better than one might think for their size. They would even take some EQ'd extension at the SPLs intended. So really both drivers have rather good wide range capabilities. Additionally, for added flexibility in the future (if/when I get a place where high SPLs are a possibility) I want to plan the design such that these 2-way WAWs could be high-passed for use with either a low 10" woofer or perhaps a subwoofer configuration.

Those are my present intentions anyway, and any thoughts or comments could be helpful as I'm starting to think seriously about the design. Though it will be slow to actually start, as I'm sorting out upstream components as a priority.

I’m attempting to build a 3 way speaker using pre made crossovers. Is it correct that I would need 4ohm woofers wired in series so that the crossover see’s the 8 ohm load it‘s rated at. And it would be the same for the midranges ?

Thank you for helping.

Hello DIYA! Earlier today I drove down to Parts Express and picked up a DATS V3 and a Dayton EMM-6 measurement microphone. With my current depth of knowledge, I have admittedly gotten ahead of myself a little bit, but nothing lightens my wallet more than the excitement of a new hobby!

I have a question for you all. I have seen a lot of variations from a lot of people of the basic idea that "your first speaker design will be unsatisfactory to you, and it is mainly through trial and error (subsequent projects) that you will cultivate the makings of a competent speaker designer".

Intuitively, this makes sense to me, but I am curious to know if this idea is articulated with a specific example in the author's mind's eye.

So, here's my question. Having completed your first speaker build of your own design, what mistakes did you find that you made? What aspects of your design left the most room for improvement?

Thanks all! I'm excited to hear your answers.

I have zero experience with speakers and I want the perfect speaker for me with random drivers in a box...I know how it sounds.
I bought these speakers 5 years ago with all drivers damaged.
Read all the reviews on 780SE.Not enough base...i got it.A passive radiator is said to solve the problem.But the 780 box is trully high quality, heavy dense construction.
The only good speakers I have around are some ITT speakers from some old B&O TV sets (big low mids , small low-mids, tweeters and supertweeters) and the Bose acoustimas 5 subwoofer speakers.
For the small low- mids and supertweeters a different smaller speaker will be placed on top of the 780se boxes . A very good midtweeter will get on the faceplate of the Missions next to the midwoofers.
The first problem I'll be facing will be the base box tuning cause the itt big low mids are bigger than the original 780 speakers but lower power.
You have the ITT speaker datasheet, but that's the only technical data I could get on all speakers and I have no ideea what those specs actually mean...
Then I remembered I read something about some active radiator tunning systems:
https://patents.google.com/patent/US20060067553A1/en
That might solve the fundamental problem of the passive radiator needed to be twice the size of the active driver.Not sure which of the speakers will be the active tunning radiators though.I'd preffer the Bose acoustimas speakers to be the active tuning radiators as I don't really need big powers but we'll see...
So I made some holes in the Mission boxes.
Way more work waiting to be done as I intend to make this system a fully active system based on Class d/t TPA and Tripath chips and a car active crossover made by Panasonic which I think is very smart for the job.
Probably in two weeksI'll be starting to work on that, but I'd like to get all the theoretical help I can get to start it the right way.

I have been thoroughly enjoying my Yamaha WXA-50 MusicCast with my old set of B&W DM-100 speakers.

However the boxes are so old and splitting on all thr corners.

I would like to use my CNC to make some new boxes up, but would absolutely love to do something a bit unique with them. I have no issues 3d designing and carving on my 1mx1m CNC fir all sorts of things.

Something to note is that I have 4 of these bookshelf speakers that I used to have hooked up on my dads Onkyo amp. At this stage 2 of these speakers are just sitting spare with the other 2 connected to the Yamaha amp.

The sound of these speakers with the Yamaha are just beautiful. I am wondering if there is a design worth looking into for using all drivers if I build 2 larger sized bookshelf speakers.

If I were to think about using 2 of the 6inch B&W woofers with the tweaters per box, is this likely to downgrade the sound?

Are there any suggestions to repurpose all 4 speaker drivers to a new designed box to use with the Yamaha WXA-50?

Is it worth exploring having the 2nd 6" in a new box as 1 front firing and 1 side firing?

Open to ideas.

Hi all, seeking 2x 15" suitable for an OB project, preferably 4 ohm.

I'm based in Melbourne, Australia - preferably seeking somethingn in AU to minimise shipping.

This is the GB for XEN designed cases for the corresponding GB for PCBs and component sets.

The cases are produced in Europe and will start production in Jan 2020.

The objective is for the cases to be ready for delivery by the time members build the PCBs and need to test the build.

Cost per case is €750 + shipping.

All materials and finishes as per EUVLs specs and design.

Payment on confirmation will be 50% total cost, remainder prior to delivery.

GB end date 5 Jan 2020....GB is Now Closed
Shipping method will be fully traceable but final solution still to be determined. some work better for some countries others require different method....learned that from the DAO Headamp GB !!!....

Limit 10 Cases !!!

Final List

Dennis Hui 1 - CONFIRMED - Data sent - Payment 1st installment -Payment 2nd instalment-SHIPPED
Lbud4 1 - CONFIRMED - Data sent - Payment 1st installment -Payment 2nd instalment-SHIPPED
Auro 1 - CONFIRMED - Data sent - Payment 1st installment - Payment 2nd instalment-SHIPPED-DELIVERED
Morde 1 - CONFIRMED - Data Sent - Payment 1st installment -Payment 2nd instalment-SHIPPED-DELIVERED
S610adam 1 - CONFIRMED - Data Sent - Payment 1st installment -Payment 2nd instalment-SHIPPED-DELIVERED
Arthur 1 - CONFIRMED - Data Sent - Full Payment minus shipping TBD.- paid shipping -SHIPPED-DELIVERED
soldersober 1 - CONFIRMED - Data sent - Payment 1st installment -Payment 2nd instalment-SHIPPED-DELIVERED
markus22ch 1 - CONFIRMED - Data sent - Payment 1st installment -Payment 2nd instalment-SHIPPED-DELIVERED



Some images as examples:

Dynaudio d280 tweeter for sale.

New and in original package. 230 Euro plus shipping (10-20 euro inside EU) or pick it up in Partille outside Göteborg, Sweden.

I'm sure this is posted before, but I can't find it...

My un-excercised (and somewhat limited anyway) electronics knowledge is failing me to come up with a relationship to give the ripple current for a given c, r and c. Is there a target max ripple recommended.?

Presumably, there is a downside to larger Rs in this case, apart from heat? I guess it increases the output resistance of the PSU seen by the amp. But again, what becomes detrimental?

Hello all
I have a bunch of audio boards coming in, and I will be building a couple of complicated multichannel systems as well as updating my car sound with some pretty intricate builds and installation. I have ordered CNC, laser and 3d printing equipment for this project

I need to set up an audio bench to measure and monitor the projects. Current interest:

• Power supply meters for voltage and current
• Amp output meters for power
• Amp output sine wave display
• Amp frequency response display
• Speaker driver parameter measurement
• Completed speaker frequency response graph

Test load
Is it a good idea to series parrell a whole bunch of 10w resistors to build some 250w 8ohm loads for further combinations to test for 4 or 8 ohms up to 1kw?

Hello all
This seems like a reasonable board. I'll be using it fitted inside the same chassis as the amp module and preamp, so the xlr are not needed. Can I run the signal directly to where the xlr are soldered?

AIYIMA Subwoofer Amplifier Preamp Board​

Secondly, the frequency range doesn't extend enough, and I would like to find out if it can be modded to range to 300hz and how. Maybe my phone repair folks can help solder that

My subs will be stereo two units per channel so total 4 passive subs, the amp 500w x2 into 4 ohms and act as stands for the mains. Is there any merit to not using a sub filter, but instead using a 2 way electronic crossover like this and running the sub amp of the low pass?

Linkwitz Filter 160Hz-33860Hz Electronic Frequency Divider​

I find these "mouse over" triggered, automated username infocard pop-ups to be most annoying - and DIYAudio isnt the only site to have taken on this fad. Is there a way to disable this automatic action? That works?

IF I want to see an expanded informational placard off someone's avatar, I'll simply right click on it. I know, so 90's - but otherwise my time is taken by waiting for the automatic assumptive action to go away, as it covers up what I want to click on.

Thanks for any info on how to accomplish this!

Does anybody by any chance still have a copy of the old minidsp MCHStreamer firmware pack V 1.7 released in 2020?? I have deleted the files and would like to roll back from 1.9. I'm just looking for the following firmwares from the pack

• DSD firmware (MCHStreamer_0i8o_sn16_DSD_v1.7_up.bin)
• AllRate firmware (MCHStreamer_8i8o_sn06_AllRate_v1.7_up.bin)

I deleted the package as i just upgrade to 1.9a.

Please PM if somebody should still have it and would be willing to share
Best

can you rec'd a usb soundcard that can be used for both measurements and stereo listening

i want something that sounds and performs good but is not hi-end, i do not want to spend a lot of money = less is best

for measurements i want to use it for speaker measurements, electric impedance and acoustic responses

i would like a usb soundcard similar to behringer uca202 but with higher quality

Hi guys

I need suggestion on affordable 100-200ma tube rectifier

Russian tube is welcomed

Thx in adv
Erwin

I downloaded the Advanced Spectrum Analyzer Pro app and did a quick measurement of my new system using a pink noise file. This is my first attempt at this so I don't have any idea what I'm doing. Is this an acceptable reading for a crude measurement? I have two sets of open baffle speakers. One set for subs and the other for mid-bass, mids, & highs. They seem to sound nice but just want to make sure there aren't major issues or missing frequencies. Thanks!

Chris