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?

Reckhorn B1 Bass Control Unit with Documentation. Great tool for tuning Subwoofers and bass units. No longer need...

Hows $85 + ship?

CONUS only...

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/

These days I started restoring an old purchase, a Cayin CDT-17A CD player that I bought years ago for a modest price, $200. The CD player had various problems, someone had tampered with the PCB to the point that it no longer worked. I managed to "resurrect" the CD player, I asked myself the question, leave it like this or redo everything, and, how to proceed? In the absence of an electrical diagram and taking advantage of my passion for PCBs, I redesigned everything, separating the various stages, Control, Power Supply, DAC and finally the Tube power supply and audio and the digital audio outputs. The result is this. Now, is it possible to improve on the original design? Does anyone have any ideas?
On the net you can find something, but nothing of that!



ORIGINAL




NEW POJECT

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...

Hey,
I bought these for speakers that weigh 130 lbs each. I’ve sold the speakers and would like to sell these.
They’re in excellent condition on top and a only a bit scuffed on the bottom.
https://herbiesaudiolab.com/products/giant-fat-glider?variant=12645160681527

$100 plus shipping

This is GB for APEX A-CLASS PSU that is designed to supply in parallel (SHUNT topology type) preamplifier and any audio circuit that needs low noise and low TIM.

Output voltage can be adjusted from +/-12VDC to +/-24VDC and max output current is set using R7 and R12 resistor. For heatsink you can use SK574-50-SA or you can use aluminium bracked that is 50mm in length, 8mm thick to cool down output shunt and ccs transistors.

This is improved design from APEX A-CLASS PSU that have improved low noise voltage reference (100uF capacitor at -IN), upgraded JFET-s that is very easy to but from mouser, and using low noise ZTX bjt for lowest noise of PSU. Input filter is RCLC and is used to suppress any noise from low frequency to high frequency. If you don't want to use L in this filter you can install two 4.7R 0.6W resistors.

PSRR is -150dB, output voltage noise is about 10-20nV/sqrt(Hz) and uses easly available TH parts! (For HLMP-6000 if you could not find one in mouser you can use standard 3mm RED LED and solder it under PCB as is in footprint).

Price for 1pcb is €6,00 plus shipping (shipping cost is from €15,00-€20,00 as these days shipping cost is high). Payment Paypal F&F only.
APEX A-CLASS PSU LIST:

nickname (number of pcb) - COUNTRY

Here is pictures of PCB that is professionally routed using all audio technique that is very important in audio psu design.



And here is how it looks when assembled in 3D (Here for GB is only PCB).



And a schematic:

Hey Guys!

I'm planning some new open baffle full-range concepts and just want to know which are the best drivers you've ever listened to.
I have a weak spot for vintage paper cones and would appreciate recommendations in this field but modern drivers are also fine.
Right now I listen to a 60s 12" Fane driver which I like a lot.. just asking myself if there are better (paper) ones.
(I know that the word "better" could be ambiguous. Of course there are modern full-range drivers that measure much better but I like the naturalness of paper cones)

Thanks for your answers!

Tim

I picked up this dead subwoofer at the weekend mainly to harvest the drivers for a DIY speaker project. (They're pretty mighty things)!
I hadn't realised the PV1D has a Hypex amplifier and I thought it would be good to try to make the thing work. Looking online seems that the OEM Hypex with the onboard SMPS are pretty problematic.
Once I'd got it off the heatsinks board I could see an area that looks like has had some intervention before. (C3 and C6). I measure 240v into these.
Also T6 looks suspect, or atleast it's soldering.
I haven't probed much beyond that area, other than various electrolytic caps, and they aren't charging. So the mains AC isn't getting far into the circuit, which I hope narrows a few things down.
Obviously we can't get a scheme for these but is there anyone with SMPS knowledge that might hazard a guess where this could have failed and possible replacement parts. Or where to do some meaningful probing;I'm struggling to see the identity of T6.
Thanks

Hey all,

I just cobbled together a sim for a UcD headphone amp. This is my first amp design from scratch.

This is a first step towards a 100W amp. I figured by ruling out most of the power stage, it'll be easier to get something working. My emphasis is simple and easy to build.

Briefly, it's built around the LT6274. One unit for the comparator and 3 as unity gain buffers acting as the power stage. Comparator output is clamped by zeners to limit output swing and not over drive the power stage.. The hysteresis is added in hopes of avoiding driving the comparator into deep saturation. There's no feadback compensation network, just a divider to set gain, and the output filter is heavily bypassed. In a rev. 2, I might revisit a proper comparator and the simplest way to manage differing supply and output voltages between that and the power stage.

I set out measuring propagation delay (285ns) doing all the math for lead/lag networks but in the end I couldn't get it to oscillate much above 150kHz, which is what lead me to rip out all the compensation and bypass the output filter. It switches around 250kHz but still has rise/fall times 200ns-300ns. It provides 5dB gain, clipping just past +/-0.8V input / +/-2V output, delivering ~50mW RMS into 18 ohms.

All in, 4 op amps, 12 passives on split 9V supplies (easy with batteries).

I'm excited to have gotten it working, but not happy about not understanding the lead/lag compensation.

All input welcome.

Hi,
How to measure and test the output transformer of the tube amplifier with signal generator and oscilloscope. How should the connections be. Can you share any videos or documents.

Is it possible to use the BA-3 front-end as a pre-amp? I think I read it can, but can't find the reference.

Has anyone used it as pre-amp and do you have any impressions on the sound? I'm currently using a BOZ-J and would like a bit more drive for a bi-amp setup running the L'amp CCS and a F5.

Thanks,

Vince

Note:

If using Fairchild mosfets, use 1K variable resistors for P1 and P2.

Volume control- 20K to 50K

Hello all!
I have this amplifier…the rectifier diodes are replaced,i dont know why,but i see the FED16BT…is this the original rectifire diode?
D5/D6 are same FED16?

My first thread, please be gentle!

I own an Involve Audio Surround Master v3 that does SQ/QS decoding, as well as a wonderful job on some stereo content of upconverting to 4.0 or 5.1. The only trouble is that the SMv3 only has analog output, and my AVR only has digital inputs (HDMI, S/PDIF).

Somebody mentioned on the QQ forums in early March that HiFiBerry had started selling an 8-channel A to D hat (“ADC8X”) that might do the trick. So I took the plunge, bought an RPI5 kit, plus the DAC8X and ADC8X hats from HiFiBerry. The ADC8X requires the DAC8X, but as with their other hats the price is not bad.

Success! I loaded up the headless version of Raspbian, added the ADC8X overlay to the configuration file, and found both the ADC8X audio input and HDMI-1 audio output ALSA cards with “arecord -l” and “aplay -l” respectively. After connecting the pieces together (SMv3 to ADC8X, RPI5 to my AVR via HDMI-1) I tried the simplest approach:

arecord -Dhw:sndrpihifiberry,0 -c 8 -r 192000 -f S24_LE | aplay -Dhdmi:vc4hdmi

This (192k/24) uses up about 7% of the cpu (according to “top”), with 48k/16 using about 2%. I could have used 6-channel mode (“-c 6”) but with 8-channels I can wire the two rear channels Lr and Rr to the 7th and 8th inputs, and my AVR will then play those channels on my rear speakers instead of Ls and Rs (as the quadrophonic gods intended!). I haven’t had trouble with underruns or overruns, but I may just be lucky with well-matched ADC and HDMI clocks.

ALSA also provides a simpler command, “alsaloop”, for this purpose. I’ll probably modify the code to add some logic to prevent underruns and overruns. I decided to stick with the lowest level in Linux (ALSA) rather than go up the audio stack into PulseAudio or PipeWire (the KISS principle).

I also have an old Korg D888 8-channel analog recorder that is nicely replaced by just recording with Audacity from the ADC8X on the RPI5.

If anyone is looking for an inexpensive 8-channel ADC, or for an analog to HDMI converter, this seems to fit the bill. The DAC8X makes a nice 8-channel sound card as well.

Hi. I'm starting this new thread about my Accuphase P-7100 amplifier clone. Most of the owrk is already done, and I just completed both amplifier module last week.
I tested and preset both amp modules today and everything is looking good. I pre-set the bias at 5mV on the final instead of the specs 20mv (20mv / 2x 0.47R = 21ma / Transistors
The front end and Meter/Softstart/Protection PCB are tested and working fine. The main +/-75V Power supply is already assembled on the chassis. It is made of a massive recycled Rotel potted power transformer, two large 51,000uF/100V Kemet power capacitor, as the original just one 35MB100A, 35A, 1kV rectifier bridge and a copper GND bus bar as the original.

I'm trying to emulate as far as possible the original, since I know the Accuphase sound and love it. I went throught the service manual and decoded the detailled BOM that list all the type of resistors and caps used where (film, carbon, MOX, carbon film, and as far as possible the same caps series and type).

The PCB, original clone of very good quality (2mm, gold plated) are from ebay. All the pcb were replica of the original and match the service manual schematic, except the Meter/Softstart/Protection PCB. The original processor amp control was replace with discrete circuit, and the usual uPC1237 protection IC, but there was no info on it, and no part values. I had to find the circuit and test my mods by myself. The input stage pcb is the same circuit but the parts ID are different from the original schematic, and some small differences are there as well. I documented the changes and wire the board accordingly. Chassis is a clone from Aliexpress.

The original amp section used 2SC5358/2SA1986 (230/15A), me I'm using the 2SC5200/2SA1943 (same 230/15A) that I bought years ago, and match them myself.
I used thermal spread aluminum bars to mount the power amp transistors, and to add rigidity to the clone heatsink made of two section. The output amp module is now solid as a brick. The amp pcb also inclded nice brass bus bar and input transistor pairs rubber caps, as the original.

Here some pictures of the PCB. There are some extra PCB such as the rectifier PCB and Softstart and Ground Lift PCB.

I have build a 2,5 way linesource with 8 Peerlees fls-0512 5,9 inch midwoofers per side, and using a Audax "gold" TW025A28 in a WG as tweeter.

Diffucult to measure with a speaker thats 152 cm in hight, and have drivers from bottom to the top.
The linesource will also be mounted on the wall, with tweeter at 3/4 up on the tv.

Measurements done with speaker 1 m obove the floor, faceing into biggest reflexfree area in my house.
measurements on 2 lower woofers together from 1 m (connected 8+8 ohm)
Done measurements on 2 higher woofers together from 1 m(connected 8+8 ohm)
Done measurements on 2 lower midranges together from 1 m(connected 8+8 ohm)
and done measurements on 2 midranges over and under the tweeter "MTM" together from 1 m(connected 8+8 ohm)
and tweeter measurements from 1 m

The drivers are then paralellconnected in pairs to 16 ohm, and then in serie outside at the xover so 8 ohms load.

Problem is that measuremenrs still become 16 ohms, and when i put it in VitauXcad nothing becomes "right"
So making simulations doesen´t help mutch, and don´t look as my test measurment on hole speaker.

And room is 3,8 meter frontwall to backwall, speaker steals 24 cm and in total with my head and sofa tha maximal listeningsdistance is 3,2 meter.

Speaker play real good today crossed at 1,5K and ca 3K (with lots of xover work), but would like to be able to do correct simulations in VitauXcad.
One more problem is my health, so can´t carry around the ca 35 kg high "thing"

Any suggestions on anything of my problems?

I have a damaged what I think is a Fishman Powerjack from a Martin Acoustic Guitar does any body have any info like a schematic there are two damaged component next to where the wiring holes are located

Hi all,

I'm wondering if I can get some advice.

I have 2 subs. DIY BMS18" in sealed boxes.
places in front corners of room on the outside of the left and right speakers. (typical setup)

I have used various room correction software e.g. Dirac version 1, YPAO, Manual EQ etc

my issue is that, even though my subs are time aligned and level matched to each other and I verify with REW. when I measure the FR of one sub, then the other sub, and then combined, most of the frequencies sum greater when combined like they should.

but there is a specific frequency that doesn't. 40 to 50hz huge null.. this doesn't happen in the individual sub responses. once combined the magnitude at this frequency is lower than that of a single sub. As if they aren't aligned.. but they are. for most frequencies. Just not at 40 to 50Hz.

if I reverse the phase on one sub they sum beautifully at 40 to 50hz, only to ruin the rest of the frequencies as this is obviously incorrect.

How do I fix this? I have read that all pass filters work to change the phase but keep the magnitude the same. But others tell me its not a phase issue but a room issue?. have I not just confirmed that the phase is the issue? I just need to know why this is happening and the correct approach to fixing it.

thanks.

Hi,
I was watching some videos from Audiophile Junkie on YT where he's covering the Montreal Show.

I saw this new speaker that looks like a G Clef that has the woofer / mid as a face to face isobaric design.
In their design It looks like each speaker is in a sealed 1/2 shell and there's a gap of about 2 or 3 inches. (Estimate from looking at the video and pictures)
see:
https://www.stereohifi.nl/loudspeak...aker-t/stereowise-l-speaker-treble-clef-audio


I'm trying to understand the benefits of a face to face isobaric design.
In some other speakers, it looks like you have both speakers facing each other attached to the same baffle so there is no gap.

So here's the questions...

1) Benefits of isobaric in general?
2) Benefits of face to face isobaric.
2a) One side sealed, other side open? (A different speaker design...)
2b) Both sides sealed, but there's a gap between the two drivers.

3) The gap between the two speakers... advantages/disadvantages ?
3a) Is there any math concerning the width of the gap?

4) What other considerations?

I mean its an interesting design... I'm curious about the acoustics. Imagine taking a 6.5" purifi woofer (extended range.)
The data sheet says sealed bottom frequency is ~77Hz, Ported drops to ~44Hz. What could you expect from a face to face isobaric ?

Is there any good material on isobaric speaker design?
I know that Mon Acoustic has an isobaric speaker (face to rear)


I realize that doing this sort of design gets expensive really quickly and its more of a thought research project while I'm out walking my Husky.

Thx

Selling two new, unused Beyma 12xa30nd coaxial drivers for 600 Euro + shipping fees. The drivers were purchased for a project that was never realized. Since then, they have been stored in a cabinet. The speakers have always been stored upright to avoid cone sagging. I live in Vienna. Shipping is, of course, possible, and if you're interested, I can check the shipping costs.

These are from my vast collection. Never used. All from the same batch.
$12/each + shipping at cost

To quench all such questions, each means one piece. Price per pair would then be $24.

Regards
Roar Malmin

My stock of these extremely hard to find 200V MOSFETs are dwindling at an alarming rate so I have to raise the price a bit.

New price will be $13/pcs.

Please also note that in many situations you can use the lower voltage ones, the 2SJ77 / 2SK214, which I still sell at $10/pcs.

Regards
R

I have been lucky enough to score said amp for a really good price, but sold as defective because the transformer humms - you can hear it from at least 2m (7 feet). The seller, knowleadgeabli in tube amps said a new transformer is needed (also mentionet that all s150 he encountered hummed).
My first question would be regarding the humm - is there something i can do to improve the situation? Also might it have something to do with the voltage in the EU (currently 230 as opposed to 220 in the past).
Another question would be regardin the mod - moving the transformer further away from the left sided pcbs.
As i have more projects started, this will have to wait a bit, until i fill a mouser cart at least, for the ageing parts (caps, diodes and trimmers).
The sad (or is it funny?) part is i have no means of hooking it up at home, as i have no preamp or amp with jumpers to use as a pre.
Pictures will have to wait.

KSA-100 used 2 of those tunnels.

Click to expand...

Speaking of KSA-100...... is anyone out there interested in persuing this amp as a project? I would definately want it to be the MK-2 version. All semi's are still available excepting the VN and VP series mosfets. These however could be easily subbed by modern IR units, perhaps using the IRF9610 and 610 devices.

This would require a new board design (Al Perhaps)? I would be willing to front the $$ to make up say 100 of them so they are available.

This seems like the next logical step in creating our own Krell Klones... then perhaps on to the KSA-80 or 160.

Let me know your ideas and opinions on this(constructive only please).

Thanks!

Mark

I still remember some silly nursery rhyme variations from my younger days.

Here are a few that come to mind. Please add more if you can remember them:

Jack and Jill went up the hill
Each with a buck and a quarter
Jill came down with two and half
They didn't go up for water.

Mary had a little lamb
And the doctor almost fainted.

Jack be nimble
Jack be quick
Jack jumped over the candle stick
And burnt his ***.

I started working on a Heathkit AP-1800 Preamplifier that lost the left channel. The included documentation of this preamp is very thorough, but many of the transistors have a proprietary Heathkit part number that I can't find information or datasheets on.
There many of these two BJT's used:
SM07275 (NPN) Heathkit Pt#417-283
SM62186 (PNP) Heathkit Pt#417-284

I pulled several and tested with a Peak DCA75 analyzer.

NPN's: Hfe 220-320, Vbe 0.770V, Vce 0.040V
PNP's: Hfe 230-285, Vbe -0.765V, Vce -0.070

BC547B/557B could be a possibility, but with so little info known about the originals, I'm not confident enough about this choice.

The PNP's have the dreaded black legs up to the transistor base with webbing connecting the three legs.
Any information would about substitute BJT's be greatly appreciated.

I am a young guy looking to fix an AVR!

I'm just graduating with an EE degree. I love all things audio and am excited to have access to the wealth of knowledge on this fourm!

I'm into home audio and all things nerdy and tech. I run a Classe preamp and amp, Magnepan front and surrounds, and 2x SVS PC-4000 subs.

I'm into cool gear and excited to see what people have got!

I'd like to tinker with some weird bluetooth modules and other components and have previously built a neat IR blaster to interface with my Classe CAV-75 since it doesn't have a remote 12v signal and can only take a pulsed turn on signal.

Hello there from Tasmania, Australia. I work on mostly amps and tape decks but sometimes CD players too (more now than before). I'm a hobbyist and enjoy late night DIY electronics.

I have been thinking about the gain structure of pre and power for a home theater amp or stereo amp with pre section being solidstate and tube

consider a tube pre with gain of 20 and power amplifier with gain of 20 log 33 or 30.37 db so how much this ratio needs to be where in tube pre I cannot change the gain but can change the gain of the power amp. I do understand the total gain ratio but what is the usual case i feel even amplifier with 26db is quite high if we have a tube pre with 20 gain

Another scenario with solid state pre with 6db gain and power amp at 30db gain so what is to be taken into consideration

For HT application
For Stereo application

Now do commercial HT amps comes with pre gain stage inbult? as the AV processor or receivers dont have a proper standard some give 1Vrms out and some are capable 3.5Vrms out
Can anyone please provide few inputs on this

Can you tell me why I cannot measure output power of a Balanced output power amp(Audio research 610T) with a crown Oc150 out control???

It happens to me all the time.

Sometimes I wake up in the morning and it’s just playing for one reason or another…in my head.

There could be a million reasons I suppose. I could have heard it anywhere.

Sometimes I know where I heard it…sometimes I can’t figure it out for the life of me.

Sometimes it’s a song I love…other times not.

This morning it was “I’m gonna sit right down and write myself a letter”.

I quickly realized a version of it was playing in the background from the Eiji Kitamura Hit Kit Party while I was tinkering away at my workbench on my Iron Pumpkin project yesterday afternoon.

Funny that it was instrumental and so kind of just snuck in there without me paying much attention.

It actually made me want to hear the song and so I went searching for one of my favorite renditions which is by Madeleine Peyroux in her Dreamland album.

What’s bouncing around your head today?

Hi everyone,

I made a trade for a pair of preowned Quicksilver Mono amps on the weekend. One amp makes an odd noise a few seconds after it is turned on. It only lasts a second then goes away, so I'm not sure if it's something I should be concerned about. It's a mechanical "whumm" sound and isn't coming from speakers. Kind of sounds like a lightsaber from Star Wars, lol. I've attached a video so you can hear it. The noise happens 12 seconds in.

Any idea what might cause this noise? I think it's one of the transformers, but I'm not sure. Amp seems fine otherwise, but I'm worried it could lead to bigger problems down the road if not dealt with. I also emailed Quicksilver, but thought I'd ask here as well in case I don't hear back from them. The seller said I could return amps if I'm not happy, so I'd like to make a decision soon.

Thanks very much.

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I thought I should post pictures of my first build.

Project was inspired by Cabasse and the curves employed in B&W 800 series, although on a much smaller budget. Had the idea to use bowls, Ikea had the wooden Blanda which seemed perfect. After scouring the net, found several others using these, although none using the 28cm versions. Design is an active 2 way design.



First completed photo (no tweeter), initially using Zero class T amps.



Current incarnation, using rotel 6 channel amp, channel for tweeter and mid, bridged for 15" sub, experimenting with solid oak sleeper stands and granite plinths.



Tweeters rather delicate positioning on top, seems to be fine without an enclosure, however I am experimenting with casting tapering tubes using champagne flutes.

The Sound: To my humble ears they sound rather good, haven't obtained a microphone to do testing. Definitely better than my Mission V63, which have an rrp of over £500. The 'no baffle' 15" add good low level sound reinforcement, as they don't go terrifically low or have very much bass

The drivers are Peerless M16GH (link below to drivers and excellent seller from eBay) Peerless & CO M16GH/4 Mid Woofers X 2 New/OldStock. on eBay (end time 25-Jan-10 10:15:24 GMT)


The tweeters are also Peerless metal domes, model unknown.

Currently crossed at 15" Sub 20-150Hz, Mid 50Hz-3Khz, tweeter 3Khz-20Khz

The sphere's come in at around 8L, (9.1L before cuts and driver displacement) One has eggfoam stuffing the other is naked will aquire some different materials for testing when I have a good mic.

They need another sand down, better integration with the stands and experiments with internal wadding, and the new tweeter housing, when time allows.

Hi, I accidentally bought a maintained contact switch and a soft start that is designed for a momentary contact switch. Is there any way to convert the soft start so that it works with a normal switch
Here’s a link to the soft start that I am using
https://www.audiophonics.fr/fr/soft...et-protection-pour-amplificateur-p-10225.html
On the soft start there is a Texas Instruments NE555P which acts as the timer delay for the soft start but I’m assume it also gets the input from the switch.
When I read the data sheet for the ne555p it said you could use it in monostable or astable configurations. Is this what I need to look at to figure it out or can I just solder the switch into two points on the soft start to fix the issue?

I’m new to diy audio but am in the process of building my first amplifier, it also the first amplifier I’ve ever personally owned. I enjoy electronics and want to learn more about audio in general. I’m very passionate about music and would like to learn more about diy music making techniques in the future.

Hello, I recently bought an harman/kardon AVR 255/230 second hand. I set it up, everything worked fine until I was setting up my Fire TV Cube to be able to control it. It tried to send some command where it switched sources (not exactly sure what it was trying to do, maybe it also had something to do with muting the source?) and since then there is no audio.
I have tried:

• using multiple sources (HDMI, digital audio, analong cinch; both back and front panel ones)
• factory resetting it with holding OK button (Tho there is a reset button in the back near the RS323 port, which I don't know how works)
• tested speakers - there is no short

Additional information:

• video out works fine
• there is no error message on the screen (both built in and hdmi out)
• while playing the test tone (speaker level setup) there is noise coming through the speaker at max volume
• noise coming through the phones port while trying to play music at max volume
  • at first after the speakers stopped playing the phones port continued to work, however i disassembled it to look for burnt components / bad soldering points / overall loose things (found none)
• I tried testing resistors labeled 0.27ohmKx2 5W KW0807 but was getting weird readings - all were 0.0-0.1ohm across them so I figure I was measuring them wrong
• I tried testing transistors behind them (diode mode on multimeter) got readings: left to middle pin is 0.6v, left to right pin is 0.6v, middle to right pin is 1.2v - this is on the ones I could access (only two of them)

Anyone have experience with something like this? Any advice on what I should try / test? I have no problem disassembling it and sending photos of things / testing individual components.
In advance thank you for any help.

hi there,
I want to sell a lot of US/Japan power plugs, the lot includes the following:

3x MPS HADES - new, unpacked, but unused, never installed on any cable.
2x Oyaide - removed from oyaide Black Mamba V1 cable and Oyaide power distributor. These seems to be unplated phosphor bronze. Used

5x Oyaide beryllium copper silver and rhodium plated. ---> these are truly special and you cannot buy them on the market. Shells are taken from other original Oyaide plugs (c037 and P004). These plugs (blades to me more precise) are made exclusively for AcroIink in Japan and were removed from US/JAPAN standard high end acrolink power cable.
Contacts: beryllium copper
Coating: polished silver + rhodium

these five plugs (blades) are IMO one of the best money can buy. I compared them to Oyaide P037, P004 . I dount count Furutech as generally speaking I am not NCF fan.

I have no usage for US/JAPAN plugs here in EU, therefore want to sell these.

400 EUR / 440 USD via bank transfer. economy worldwide shipping included. This is my best price already. If youre into DIY'ing power cables - try these five oyaide plugs and you wont be dissapointed.

A thread for discussion on all purifi driver builds.

A place to brainstorm and speculate on drivers and potential speaker builds for arguably, objectively, the best no-nonsense engineering-first traditional speaker drivers' money can buy - If you have a complete project underway, please start your own thread and post a link to it in here. Otherwise posting occasional random progress pics and info here is fine but we will keep full build discussion elsewhere.

We are also pleased to have @lrisbo of purifi occasionally check in and post here of which is much appreciated.

A tweeter is on the way 🤓

Updated 26/01/23: Added more build links and intro - (I may stop updating commercial builds moving forward as they are now coming in thick and fast)
Updated 16/06/22: Added builds and review links, updates to builds
Update 17/03/22: below

Time for a bit of consolidation due to this thread getting some hits, and purifi has now released quite a few scrunchy woofers

Links to known projects & commercial speakers using the Purifi drivers (please PM me if I need to add any)

Of course - www.purifi-audio.com , and the team behind the drivers here


Full DIY:

DIYA user @spresto9 has come up with these beauties with the 8" purifi woofer like to details and more pics HERE




Check out this 4" pocket rocket proof of concept build from the Purifi team - all the info you need to DIY!

Spk8 appnote download (.pdf)



@lrisbo Proof of concept Purifi SPK4 (superseded) - Passive stand-mount



@lrisbo Proof of concept Purifi SPK5 - Passive stand-mount - I believe these were at some point being made and sold commercially but have since been discontinued - there may be some floating around second hand market see here Celuaris SPK5 review ASR



@xrk971 PTT6.5/RS28F Waveguide Harsch XO - Passive stand-mount later evolved into a nice Stand mount and Floor standing Transmission Line



@Joe Rasmussen Somewhat Legendary 'Elsinore' - Has been given an (expensive) purifi remodeling. Wow. Skip ahead to post #4,746 for the juicy bits.




Rick Sykora and team's Directiva - Active stand-mount with excellent (objective) reviews, requires external amplification for each driver and an external DSP crossover.





@xrk971 's Raal 70-20xr and PTT6.5 - this one the tweeter is not readily available to DIYers but there may be ways to get it if you're crafty.

(sorry X, couldnt find a finished pic, and I'm out of attachments for this post)


User tktran303's Collection of DIY designs here looking great




Some mindfood for the 8" - a concept by Purifi.



Paul Carmody's Virage - a full design, light on measurements but a fairly reputable designer.



.....and many more concepts within this thread, start reading. Most not fully documented or taken to finished stage though I suspect a few people are still perfecting their builds before showing them off. Remember you can drop people a friendly private message asking about how their progress is going.





DIY-Kits/Semi Commercial:


Yevgeniy’s PuriWave - 2-way stand mount with dual purifi passive radiators



Troels Gravesen Purifi 6661 - Semi-passive/Active plate amplified floor-stander



Troels Gravesen Purifi 6R - Passive bookshelf




Troels Gravesen Purifi Be - Looks like a revision to the above due to ribbon tweeter supply issues.




hificompass Puri Bliss BeWg - Passive bookshelf - I believe the plans are/were for sale.



Joseph Crowe's 1198 - I believe you have to get in touch via the webpage - floor-stand transmission line








Full Commercial:

March Audio Sointuva - arguably where "the bar has been set" for the Purifi 6.5 in a bookshelf chassis.



Jones Scanlon Baby Reds - self powered studio mixing monitors.



The Late Rick Craig's Selah Audio Purezza - A nice stand mount ribbon tweeter design, was available commercially but afaik discontinued, check SH market



Jachim Gerhard Surveyor's - stand-mounts , I believe there is/was a floor-stander made too



Dennis Murphy & Jim Salk's BePure2 - Floor stander - The legends behind the philharmonic BMR and BMR tower



and um, what ever this might be! https://www.audiocircle.com/index.php?topic=175599.0 - probably just a concept, I didn't read the thread. Likely Unobtanium tweeters and probably bottomless pockets required, if it is sold commercially.

Correction - the above was a concept which later evolved to the BePure2 - see this thread at AVSForums Post #10,174
https://www.avsforum.com/threads/th...rs-and-discussion-thread.939744/post-61186397


Further Build links:

Thrax Siren - a 2-way standmount

Jern 35 - 2 way standmount

Buchardt A500 Signature - Active 2 way standmount

WVL Serendipity - 2 way standmount

Taipuu Kero L active with FourAudio PPA-1000 dsp amps. - Not sure if available yet

Salk Sound BePure3 ... Holy **** I need to hear these.



Links to independent driver reviews:

https://www.erinsaudiocorner.com/driveunits/purifi_4/
https://www.erinsaudiocorner.com/driveunits/purifi_ptt65w04/
https://www.erinsaudiocorner.com/driveunits/purifi_ptt80x04-nab-02/ - the eight inch aluminum mid-woofer
https://www.erinsaudiocorner.com/driveunits/purifi_ptt6.5x04-naa-08/ - the 6.5 inch aluminum mid-woofer
https://www.erinsaudiocorner.com/driveunits/purifi_ptt6.5m-08-nfa-01a/ - the 6.5 inch dedicated midrange

Also - please consider visiting Erins Youtube Channel and subscribing! - a much needed light in the dark world of audio subjectivism.

https://audioxpress.com/article/tes...udio-6-5-midbass-transducer-from-purifi-audio

https://hificompass.com/en/reviews/purifi-audio-ptt65w04-01a-midwoofer
https://hificompass.com/en/reviews/purifi-audio-ptt40w04-01a-midwoofer
https://hificompass.com/en/reviews/purifi-ptt65w08-01b-ptt65x08-nfa-01
https://hificompass.com/en/reviews/purifi-ptt65m08-nfa-01a-65-true-midrange

http://www.troelsgravesen.dk/Purifi.htm


Original Post 02/04/2020:

With the group buys well underway the idea was bought up that a design thread be started to discuss build options.

Mine have arrived but I have no build materials and will not be able to get any until we come out of quarantine in (hopefully) three weeks time. I planned to start with a hybrid of purifi's SPK4/5 builds using the same AMT tweeter but maybe using a slot port with the 2.5khz crossover. That and I haven't done any AMT builds so it seemed like a good place to start.

I read of a guy in Aus planning on doing a line of passive and active speakers with the woofer so be interesting if he could chime in here.

So with no materials for the next at least 3 weeks, what better time to discuss build options! Fire away

It is finally the time to post my Scinnies...

One Ohm model. One speaker OK, while other has bass ribbon panel damaged & removed...a multimeter fell onto the foil as I was completing the "Silicone fix" years ago (still have not gotten over it)...

• Both tweeters are there and functional, albeit both ribbons appear stretched.
• I do have a pair of replacement Bass Foils (actually the entire Kit) from Patrick in Germany that I bought many years ago (not cheap at $1300).
• Covers are painted Matte Black (used to be that ugly Beige)
• Been sitting in my back room past few years....wife would like them gone.
• Pics taken years ago attached...

Pick up in West Sub of Chicago, no shipping. I also cannot assist on the repair.


Asking $1500.

A less-than-two-minutes, eight years old news video of a man who paid for his own utility transformer and pole to get "pure electricity." I vaguely recall reading about such a person years ago - perhaps it was this man, or maybe there's several who have done this:
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