Hi forum friends,

My first post here. I hope this is the right section to post.
First some info on myself. I am a beginner in electronics repair equipped with a basic digital multimeter, a 40 watt soldering iron and an esr meter. Willing to learn more if someone can guide patiently.

Last week when i switched on my pc to play some mp3 on this Sonic Gear speaker, i noticed the music is coming from two side satellite speakers but the bass(woofer) speaker no sound. Normally the bass will pump out some vibration. I fed dc3v to woofer speaker red and black wire at sp near cap c23, it had some speaker crackling sound. Fyi, the woofer speaker positive side is traced to 4th leg(output) of Tda2030 audio power amp at the bottom middle of img095833 while negative side is traced to yellow 104 cap at c27.

Using my dmm, i do voltage check at 8 pin op amp 4558 by positive red probe on pin 8 and negative black probe on center tap of transformer. Got 9.1vdc on both amp.
Another voltage check on tda2030, positive red to pin 5 and black negative to center tap transformer on all 3 pieces shown 15.7vdc.

I did 200ohm resistance test on those tda2030 by pin4 output to pin3 ground, the tda2030 near subwoofer speaker line showed 5.1 ohm.

Appreciate very much for anyone kind comment and suggestion on making the bass to come back again. Thank you in advance.

I am new to speaker measurements how is my system looking? Just the left speaker measured.

open image in new tab to view



Topping Dx7pro
Pass DIY Lxmini Analog crossover
Elekit TU8600 amp for high freq drivers
Audio Reasearch 150.2 amp for low freq drivers

Hi all, I am new members here, and still learning about electronic circuit. I have plan to making a equalizer with 24 channels stereo (24 channels/mono). So I have problem dan confused to determine for value of "Q". Can u give me a suggests, what is the better value of "Q ' at +-10db for my equalizer? Or u have suggest a schematics for my project. Thanks a lot.🙂

Sean Connery, Hollywood's Quintessential James Bond, Dies at 90. (People)

Here's a few parts for solid state amps I have listed on Ebay.


1) Pair of red heat sinks: Set of 2 Red Aluminum Heat Sinks for DIY Audio Amp or Similar Project | eBay


2) Large heat sink:Large Aluminum Heat Sink for DIY Audio Amp or Similar Project | eBay


3) Lot of 8 pcs BUV39 TO-3 NPN power transistors:Lot of 8 BUV39 NPN TO-3 Power Transistors - Unused old stock - Pulls - Reduced | eBay


Thanks for checking.....

A very nice and clean LR Phono build that I finished recently.
I used a Linear Audio SilentSwitcher with external D battery back.
Based on my rough calculation, that should be good for about 80hrs (for 4 batteries)
You can also use a 5V wall-wart instead with the SS.

Vampire RCA sockets and nice vintage brass binding post.
Unit is in a compact chassis by Landfall Systems.

Sold as described above $450 shipped (over $70 less than parts)

I can also offer this without the SilentSwitcher for you to provide your own ±15V PSU, for $370.
* I have a ±15V AMB sigma22 with Triad shielded toroidal transformer which can be used as an external PSU.

Build costs:
* PCB -- $41
* Inductors -- $127
* OpAmps -- $64
* BOM -- $82
* Chassis -- $98
* SilentSwitcher -- $88
* Battery pack case -- ~$20
* Total -- >$520

For sale is a Tubelab SE-II 300B power amp with ISO (ex-Tango) Iron

I built this amp last year with the intent to build/buy high efficiency speakers. That didn't happen so it's been packed away and I'd rather have someone enjoy this great amp.

It is a premium build, no expenses spared.
The amp will come with a pair of NOS Raytheon 5842, but not 5AR4 or 300B.
If you prefer to have an integrated volume control pot, I can add that for you after the sale.

I am asking $1650 (was $1800) shipped, which is below the cost of parts.
Consider, the ISO iron costs around $1050.

IMPORTANT: The TSE is fixed bias and requires adjusting the 300B and 5842 bias with a multimeter. The 300B have test points in the rear for easy access with the amp closed. The 5842 require attaching a probe to the coupling cap. Only purchase if you have experience and are capable of handling the high voltages present in tube amps.

Detailed build info:
- ISO transformers iron -- FC-20S opt, LC-10-200DII choke, custom PT.
- WBT 0708-Ag NextGen binding posts.
- ClarityCap TC 85uF 600V Polypropylene PS cap
- Mundorf Silver, Gold & Oil 0.1uF coupling caps.
- Resistors are Takman and Kiwame MF and CF.
- Mills MRA-10 non-inductive for the high wattage resistors.
- Mogami W2546 coaxial input wiring.
- Kimber TCSS 19ga wiring.
- Chassis by Landfall Systems

B+ is around 385V, bias at 80mA.
Currently using the 5K:8R tap, there is also a 3.5K tap if you prefer that operating point.

I bought amp for a future 3 channel active stereo project and will make a few upgrades the 5 headed beast. And living in SF made a little easier to source the schematics. Enjoy.

Hi Folks,

First let me start by saying that, in my humble little part, I am very happy to be part of this community !
Although I have subscribed to the channel already quite some time ago, this is my very first post, so first a short presentation is the least one should expect :

My name's William, I'm a 50 years old French/US citizen, have been living in China for over 6 years now (Beijing). I'm an interior designer.
I love audio and music of course, music is an important component in my life and well being. I listen to all sorts of music really, but probably 50% +/- goes into house and techno, as I used to DJ before (in the 90's, also in China, after which I went back to France for 14 years).
But Rachmaninov, Tchaikovsky, Queen, Supertramp, Bowie, Bauhaus, Ella and Louis, Dead Can Dance, Muse, and so many so many more...they all sound great to me, so I am quite eclectic.
I don't spend hours in audio stores or what, but back some 18 years or so ago, at my best friend's place in Paris in listened to some music (it was hardcore techno !) coming out of some old speakers wired to an old tube amp he had found at the flea market back then.
And let me tell you, that sound ! My first time listening to a tube amp...I was convinced !

A few years later I got my first little tube amp (a hybrid actually) that eventually, after some run-in hours, finally kicked-in one day, when listening to Adele at the Royal Albert (could find worse choice for a kick-in, right ? 😀) while having lunch (The sudden difference in sound almost made me drop my fork).

Anyway, since then, I always wanted to go "Rogue" aka DIY 😉 because...well just because !
But never had the time before now.
But now, finally, HERE I AM !!!

So, now, for the project :
1 - My Goal : is to build a pair of speakers that are fairly to very efficient, each with a single full range driver, that can deliver a rather clean crisp sound and rather fairly flat all across the spectrum, right out of the speaker without any electronic assistance.
Bass has to be full and rich all the way down to the low 40s (even lower would be better uh !).
The cabinet doesn't need to be a tiny small one, as I am not looking to do a bookshelf speaker but rather more something that looks like a statement in the room.

2 - Components :
The Driver :
6 months ago I bought a pair of 6.5" full range drivers - aluminum cone - these are from a Chinese brand that some of you may know called Lii Audio.
I'm not gonna bring up all the TS for now, but for a rough idea :
SD = 132cm2 / Qts = 0.617 / Vas = 29L / BL = 6.349 / Fs = 42.853 Hz / Spl = 91.8 db

The cabinets :
Using Hornresp, I designed and then built a pair of MLTLs for my drivers. In the end they look a bit like some MarkAudio pensil series.
I used no BSC, because I don't want to loose on efficiency (more on this later) however I did try and minimise baffle diffraction (at least for mids and Highs):
The Baffle part where the driver is placed is on a recessed panel of 20*20cm, and which I then covered with a 9mm thick sound absorbant material (looks a bit like some kind of very stiff felt) that I use for covering walls in home theater rooms when I design homes.
Of course I cut a whole of the size of the driver cone in this material before putting it in place.
When playing music, the difference in the sound is very noticeable whether putting on this part or not, so clearly it is having an effect at canceling or reducing some of the baffle diffraction.
These speakers are (internal dimensions) : H95cm * W20cm * D33cm.
Fb is tuned at 35Hz or 40Hz that just depends if i add or substract an additional layer of plywood (18mm thick) in the horizontal vent located at the bottom of the front baffle. However placing this additional piece or not doesn't to make much of a difference in the end when listening.

The Amp :
A chinese tube Amp that's got a lot of good reviews from everywhere (the audiophiliac among all but not only).
It's the Reisong A10, Ultralinear, with El34B tubes, 6W per chanel.

3 - My impressions up to now :
For a first try, I would say not too dispointed, but can't either say completely satisfied !!!
First I placed the speakers about two meters appart, in a room that is about 5-6 meters wide.
The sound coming out was ok but...the bass seamed a little slimish if I placed myself in an about equidistant triangle from both speakers (a more or less normal listening position)
But then if I placed myself almost in line between the two speakers then the bass comes out. So there is Bass.
So then I tried placing the speakers close to the corners of the room (about 80cm inward from each corner) and tilting the front baffles toward the center of the room aka the listenning position and then...Tadah the bass wasn't so slim anymore.
So yes there is thumping bass coming out of these but depends on the position, cause it seems like a lot of it is leaking on the sides.
Then, as there is no BSC applied, I'd say the mids are a slightly too present sometimes, but IMHO it's in an acceptable limit still. As for the highs they feel fine to me.

4 - But then I do have a bunch of problems/questions :

What would you suggest for that bass "leaking" on the sides problem ? BSC ? Change cabinet - side vs front&back - proportions ? You see, MA's pensils designs specify that these cabinet designs don't realy require BSC, so I figured that My design, very similar to a pensil, could also get away without it.
External dimensions are 23.6cm wide (front baffle) x 40cm long (sides). What if I inverted these proportions ? What's your experience with this ?
Could it be some kind of bass cancelation in relation to phase or something else ?
Or could it be that my alignment isn't that good ? How should I calculate this then ?

This brings me to another important question : how far can I trust Hornresp in the design of my MLTL ?
Any other serious software options for MLTL ? (besides MJK's mathcad work sheets).

Then, something else that is bothering me is the power :
Granted, it's only a 6W per channel, but if I want to feel a bit of power in the music, I really have to turn the knob all the way up ! the room is basically a 6x6 or 6x7 meters wide.
is that too much for my combination ?
To be honest I am more suspecting the driver or the amp to be wrong somewhere :
a) When running the specs of the driver in WinISD, it tell me that driver's spl is in fact 87db ! If it where you, would you believe more the written specs or what WinISD calculates ?
b) As I mentionned before, my tube amp is an ultralinear one, but nowhere can i find the amp resistance output. What I am saying is I don't know if this is actually a high Z amp or not. It is An SET though, as far as I know. So should I consider it a high Z amp ?
And if yes, am I then right to assume that it is because it is a high Z amp that it's not putting out as much power as I would hope...especially if the drivers are in fact 87db one ?

Should I just change drivers ??
If Yes, for what I want, which one of MA would you recommend ? I am considering CHN110 or CHR120. What do you think ?

OK, I am sorry if some of you think this post is just too overwhelming, but I have great respect for many of the people in this forum, you guys know so much, so I sincerely hope you can provide me with hints or answers.

Those of you who will have read it all, thank you for your patience and understanding !

In these very difficult times I truly wish you all the best.
Stay safe, stay very safe ! Don't do anything stupid.

My Best regards to all.

Need the Power supply schematics of this sony TA F-6B

Any one all help is welcome.
Now the 3.15A fuse is blowing all the time.

Thank you all

Max

has anyone used this tweeter with or without the matched waveguide? or maybe some measurements to share?

Hello All,
I've been trying to ask for help as little as possible, I tend to learn much more when I have to figure something out, but this one is something I don't understand.

When I got the amp, the power FETs were shorted out, so I replaced them.

This amplifier will show a normal signal on the power FETs when the rectifiers are out, but when they were in I get this... where it's like two or 3 waves over top of each other. When the power FETs were out, I had the same signal. I thought maybe it was the driver, so I replaced that, but clearly it didn't help.

I thought maybe someone would have seen it before or have an idea what causes it. I'm all ears!

Hi all,
I am restoring a Raytheon RC10 tube broadcast console from the 1940s. The large (4") Simpson VU meter is not working.
I have taken the meter apart, and inside the meter there are two wirewound resistors. The resistor that attaches to the + input terminal is open. I am trying to find out the correct value for this resistor. Can anyone help me?
Thank you
Tyler

Does anyone know what the current / definitive Harman room curve is? I've seen numerous variations around. Some folks say a curve from a given low freq. right to 20k, others say flat to a mid freq. then curve down to 20k. It would be nice to know the real deal.

I haven't put together any circuit in years. I'm looking for a project, but I've already got tons of stuff sitting around. 🙁

I've got lots of time now that I'm mostly unemployed.

Hi, I built the following reamp box.


The purpose of the Ground Lift switch is to connect/disconnect the shielding of the transformer to Sleeve/Pin 1 of the XLR right? I am concerned that as is it will not have a difference since the audio transformer signal depends on pins 2 and 3 right? Am I mistaken to think that grounding or not the transformer will not have any effect?

Thanks

Hello everybody ,
could you tell is the wharfedale linton heritage 2.5 or 3 way ?
does the 5" MID driver , is it just for mid ? or also for the bass ?

I have MANY projector parts, too numerous to list, that I will sell CHEAP so long as you pay the postage. I'm in Dallas, Texas. 75021

Triplets - 3
Frensels - many FL and sizes
LED - 4 100 to 130W
Heat pipe units - 2+
LCD screens - 10.1 @ 720p, 10.1 @ 4K, 7 inch (res ?), 5 in (res). All have controllers
Condenser lens for LED - many sizes
Power supplies for LED

Many fans, but you can probably source them locally. Some squirrel cage fans that are good to prevent light leakage.

Email me at est6516@verizon.net with what you're looking for. I'll see what I have and send you photos and asking price.

Chaz

Hi

I have a Stax electret phono cartridge which use 2 x 2SK53 FETs inside it. I have to replace these FETs but can't find any data on this obsolete FET

I would be happy if someone can give me the data for this FET.

Thanks a lot

Can active subwoofer only mount below passenger seat? Can I mount also at rear seat flooring
To prevent the bumping to the passenger seat

Hi All,

I picked up a pair of Maggies over the weekend for $100 and am preparing myself to endeavor re-wiring these things. I can get the full re-wire kits from Magnepan for about $120 (does both lf and hf, both speakers). At first I was hesitant, but after reading about the work required, getting them for the right price, and a call to Magnepan (who were very helpful!) I decided to give it a shot.

So far only the treble sections have open circuits, but the LF section in the right speaker has a spot that is becoming undone (it was taped over).

Interestingly enough I plugged them into my system and they sound surprisingly good! However, I am sure that they will sound even better once they are completely rebuilt. I'm also planning on doing some aesthetic improvement as well.

They came with no covers, but as I look at them now, I'm not sure I want covers. They are flat black right now, and I'm not sure of what the challenge would be to paint them without actually making anything worse. IUf anybody has any ideas about painting the aluminum on the front side, I am all ears. In the mean-time I'll at least give Magnepan another call and see what they say.

I kind of like how they look without the covers, and wonder if along with some faint back lighting if they wouldn't look even better!

Oh well, first things first: ordering the wire kits today so I can get started, and talk to Magnepan to see what they say about painting them on the front side. 🙂

If anyone has any experience with this type of job, I am certainly open for any suggestions, or any thing I should be aware of and to look out for during this process.

I am on my way to finish a three way and I already have those two cables:

CS - 12 HF (halogen free) - Van den Hul B.V. - High End Cables, Phono Cartridges and Electronics

And

The Siren Speaker Cable | Evidence Audio

I need your recommendations on internal wire between those two.
Is there a path that I should follow?
For example use the thicker(at least I think is thicker) van den hul for the woofer and the evidence solid core for mid and tweeter?
I find very few info on the evidence solid core wire but it costs double the money, so I guess this is a sign that is superior or something?

I read what "each tube have floating cathodes should use independent heater".
I do not understand why. For example, I use 3 tubes outside of audio path signal, one have 250V cathode potential (EZ80 rectifier), other cathodes connected to GND (EM800 indicator and TG1 thyratrone).
Each tube maximum cathode to filament voltage:
EZ80 500V
TG1 0 to -50V
EM800 +/- 100V

So, in that case I can connect all 3 filaments to one supply.
Is it correct, or should I connect middle of winding to ground, because EZ80 may give some positive voltage on heater(?), but it is not possible for thyratrone.

Hello ti everyone. I'm assembled a couple of mx50 se board kit. But i've got a problem. The offset at the output from a board Is negative and the signal Is highly distorted. The other works fine. Both powered with 20 +-v DC. I'm not so experienced with the solid state. Never problem with the valve. What' s happened?

Hi, I have an ASR mini basis phono preamp. I have made some upgrades to other components with discrete opamps from different brands: Burson Audio, New classD, Sparcos ... and I have always liked them a lot. My intention was to use one of this type to improve the ones that the Mini Basis integrates. However, when requesting information from the manufacturer, it tells me:

The AD 797 is from input stage- has extremely low noise- there are only a few opamps that can be used

The AD 843 JN is for output stage- you ned an OPamp with adjustable output offset.

Only very few can be used.

The socalled “discrete built” opamps from Burson etc. can not be used in the Mini Basis. Have too high noise and to low gain.

Can someone provide me with information about an alternative model of better quality than the above mentioned opamps? It's a shame the door is closing on discreet opamps for this application. In my cd player, for example, the improvement was very big.

BR

Toni

I tried to do class d UCD with the principle as pictured, it worked quite well in the first 5 minutes, then it was blacked out in a very loud speaker, along with 4 very hot 2n5401, I tried replacing the other 5401 still not better

Hi, I have just got a vintage SAE I-102 integrated amplifier.

After visual checked. I found a resistor burn and difficult to recognized its value from marking code.

It just barely be recognized as:

"brown-black-unknown-black"

But the measured value is 0.4K ohm. Therefore I believe the resistor has damaged. Again, it frustrates me as the last band is black. Is that mean this is the type of fusible resistor? with temperature co-efficient? Or current sense function?

Anyone can help me to find out the value of this resistor?

Thanks!

CW

Hey Anyone,

Has anyone ever heard of an amplifier using 6AS7GA output tubes? I first saw them in Bruce Rozenblit's OTL power amp. They were intended for use as DC amplifiers not as audio tubes. But in looking at their specs they are really interesting. Its a low mu twin triode, mu=2, with and extremely low plate resistance of 280 ohms. I'm assuming that if you parallel a single tube the plate resistance would be 140 ohms and then if used in push pull the plate to plate resistance would drop to 70 ohms?

If the 70ohm plate to plate is correct, (My math is always suspect.) in push The output transformer would need a turns ratio of 2.95 to 1 to drive an 8 ohm load. With such a low turns ratio the drawbacks of an output transformer would be minimized. It might even be possible to use a toroid?

But the real question? Has anyone ever heard this tube? Would its sound be worth building an amp with it?

I have a Placid 2.0.1 built by someone else.

I have followed the set-up instructions in the manual to the letter with VR1 at 100 ohms and VR2 at 10Kohms with no load connected.

The Placid is fed by a 15VA 230V transformer outputting 8.8VAC.

When I turn on the power, there is no smoke (!) but also neither LED lights up. (I have checked that they are mounted in the correct direction of the flat side as per silk screen).

I can adjust the output voltage to the desired 5.0V with a VR2 value of 20.78 Kohm. But the R8 voltage is 0.0mV whatever value for VR1.

Be grateful for any advice as to what might be causing the LEDs not to light up, before I dare to attach a load to it.

Thank you

Sorry if my searched missed a probably self answering question, but I have little experience with SMPS.
As I want a +/- 15 to 18V supply, there is nothing from stopping me from using two wall-wart SMPS supplies with the output reversed on one for the negative rail as there is no reference to any common ground point with respect to the AC in. Circuit ground being the center.

Hi all,

I'm currently restoring a KEX-M900 which came to me as a dead unit.

So far I recapped the DC to DC converter

Recapped the main board, ASL board and DSP board

The unit now powers up, display is good, all menu's working too.

The problem is the unit has 4 pre outs and I have only one channel with good clean audio.

I would like some pointers on tracing the audio path to see if I can find where it's losing audio signal to the dead channels.

What I know so far-

I've tested 2 audio sources

Cassette working fine
Aux input working fine

Both with the same result - audio on one channel only

The dsp board is labelled FR FL RR RL where it outputs to the main board and into the ASL board, I intercepted the signal off all 4 channels and it's only outputting audio on one channel so I think the problem lies within the DSP board or maybe just before it?

I've come this far so would really like to troubleshoot and find the problem, any help or suggestions appreciated

I have a service manual pdf if required

Thanks in advance

I suspect some of you will be very glad to know I have reworked Legato a 3rd time. This time is pretty significant in that there are no coupling caps *at all* - zero - zilch. For those of you craving the purest possible bass and mids. This is it.

The 3rd major version of Legato features trimmers that allow the user to trim out all differential and single ended offset. So, now you can obtain DC coupled bliss.

One important thing to keep in mind is that while the differential and SE offset can be completely zero'd out, there will be common mode DC on the balanced outputs. Most balanced input amplifiers (Sympatico especially) will not be adversely effected by this at all. If your amplifier cannot handle the small amount of common mode DC (6-7 volts) then you will want to add external coupling caps. But this would be a rare case. I do know of some (mostly tube amps) that have center tapped transformer inputs, those would need caps.

Many of you use single ended outputs and those are also completely free of DC once trimmed. No coupling caps needed here ever.

I have been listening critically to this module for about two months. I really am very pleased with the result. Of course like its predecessor the noise floor is way beyond inaudible, and the THD is improved by the fact that there is no cap to add distortion effects at the output.

Now the extra good news. I am so pleased with this module in my initial testing that I have already drawn up one small optional enhancement - an LME49600 in the feedback loop of each SE output. This revision will be Legato 3.1. It is designed for those who want to drive headphones directly from the output stage. One nice feature is that you can easily make the buffered outputputs work SE or Balanced with either one(stereo) or two (dual mono) Buffalo(I or II) DACs. I will describe that setup in more detail in the manual.

We should have both modules available soon. The Legato 3.0(no buffer) version will be available first.

As always a picture is worth a thousand words.

Cheers!
Russ

Hello fellows from DIYAudio,

Oh... my first thread, after one year of participation here

Here is my new construction using polypropylene cone speaker and aluminum tweeter of the SB Acoustics. This is not anything new. Designers like Troels Gravesen have done their versions.
This project was born of a need and a curiosity: I was curious to know the results so acclamed about the high Qm speakers***, and so I chosen this SBA. Also chosen why I had not yet experienced playing with polypropylene speakers, and maybe it was the kind of sound I was looking for ...
I already had a pre-assembled box, only missing the front. Time to apply the speakers! I decided to imitate Troels using stepped baffle and LR-2 crossover. The point is that Troels no longer publishes the crossovers values, and rightly so, given the circumstances that occurred to him. And their project do not match 100% with my project, which differ in dimensions. Time to learn more about crossovers!
Soon I publish some measurements and the resulting crossover after some iterations. But I advise here: I'm a newbie about acoustical measurements, and my apartment is small, so everything below 1kHz or so is a disaster... 🙁😱 but at least the cross point is higher than that.
And is a working in progress: if knowledge permits, some refinements are in order

***but I have much fear about power compression, due to lack of the inherent "heatsink" in this fiberglass former, in comparision with the more common aluminium VC former.

Anyone have a single SB17NRXC35-8 woofer. Just need one. I need the original NRXC version, not the NRX2C.

I have an Azur 640A V2 that's going into the "three flashing lights" protection mode after about 15 minutes of use. (I've attached the relevant snippet about what three lights indicates below.) It does this hooked up to 8 ohm speakers and being fed music, as well as with an 8 ohm dummy load and fed a 1kHz sine wave.

From what I've observed so far, it appears to be a temperature-related fault. It doesn't happen right after power on. Once it does go into protection, unplugging and plugging in the amp resets it, but then it more or less immediately trips again, even without a load connected and no signal being input.

I know there are a number of diyaudio members who have (or had) this amp, and so I wanted to see if anyone has encountered this particular fault before I dive in to begin troubleshooting in earnest.

I want to experiment with different back chamber configurations on the SB26ADC, but i am already struggling with getting the plastic back cup off. I'm guessing heat is the answer, but i'm wondering if there is anything in the motor system that can be ruined by too much heat. If not then i can try baking it at 100C or so. Had no luck with a heatgun so far. The front plate with membrane and voice coil is disassembled prior to this obviously.

Any experience or tips?

Hello!

I bought about a year and a half ago some SB Acoustics drivers. I haven't found the time to build the speakers untill now. But I managed to get a 1 week vacation, got my best friend to help me build them (I have 2 left hands) and started to work.

The speakers are:

2 x SB Acoustics :: SB29RDC-C000-4
2 x SB Acoustics :: 6" SB17NRXC35-4
4 x SB Acoustics :: 8'' SB23NRXS45-8

I have simulated the speaker using Boxsim and both the manufacturer's FR graphs and the graphs form Zaph|Audio
Results:

Frequency Response:


Phase:


Directivity:


The crossover:


I considered they are looking good, so I started to build the enclosures:



















And the crossovers:

Just heard Microcap is now free. Ive been a Ltspice user for a decade but never tried microcap and would like to know the differences and if its worth learning. Anybody well versed in both?

Thinking on how to reduce the power line noise and harmonics across my system. There is so much misinformation out there, like shielded power cords. Copper or aluminum foil does not shield magnetic waves, so totally BS. Even my good DIY inter-connection cables are just multi-layer copper strands, not high permutability steel. ( Belden stranded 75 Ohm)

Is there wire that is shielded against LF?
I can find thin nu-metal sheets I can use for inside box shielding, but surprised I can't find "utility" boxes. Only tiny ones for little audio or switcher transformers.

Does twisting a power cord, say 5 or 6 per-inch is possible with zip cord, reduce the magnetic radiation to any useable effect?

Is there a source for small toroid power transformers that are encased one can afford? Or even small e-core. Like a coupe amps, 36V ct

Getting new respect for remote supplies. Tempting to pull stuff apart and make a central rectified supply. Maybe a bigger switcher and some buck regulators to drop the outputs to what each board needs. Space is a pretty good shield too.

I have a Pomona test lead holder that is lightly used. Asking $5 plus shipping from zip 17403.

PM if interested.

Thanks

Hello everyone,

i finally decided to start with my speaker project and i am trying to gather the top-tier active kits/concepts/plans for that. Seems like i am struggling to find promising candidates and need some help on that.

I can't design a high-end speaker by myself (lack of knowledge/experience), but i can follow any given and verified plan. The tasks i can't do myself (e.g. cnc and painting) will be done by professionals, but i am quite confident i can do most tasks on my own. I don't have the money to shell out 30k for a commercial speaker, but i am willing to put quite some time and money into a diy project.

I am looking for a full range active speaker, that allows precise DSP-tuning to match the room it is in. It should work in rooms up to 40m², although my current room is somewhat smaller. I am not sold on any drivers or even type of drivers or type of speaker. I listen to a broad spectrum of music, with a focus on rock / blues.

So far i came up with the various Linkwitz speakers, esp the LX521 looks interesting. I found some kits in a german shop (Duetta aktiv), some other very interesting builds but without published plans and aloooot of passiv kits/concepts.

What outstanding active speakers am i missing here? I want to gather a list of candidates, narrow them down, listen to them and then decide what to build.

Looking forward for your suggestions, fire away 🙂

Good Day,

I have designed and tested a valve heater regulator using a LM317 but am keen to use a LDO regulator (< .75V DO) to reduce both the component count and power dissipation across the regulator. Only caveat is that the heater voltage is elevated to 140V. So does anyone have any suggestion for a suitable regulator? The heater voltage is 6.3 V and there are two in parallel ie .6A although I can run them in series (12.6V @.3A).

Also what rectifier diodes are recommended, anything special or would the UF4007 suffice? One with a low forward voltage drop would be of benefit.

Thank you,

Hi everyone.I want to build stereo slim subwoofer towers with shallow subs.(want to add different bookshelfs,fullranges on sub towers in future)
https://www.intertechnik.com/media/1382436_124227.pdf
and
https://www.intertechnik.com/media/1382315_124171.pdf

It seems items are same except colors but black ones recommendation have 10-17 liters box and silver one has 40 liters.Is there any mistake with datasheets?
Regards

Hello guys,

first I would like to apologize if I did something wrong (put this thread in wrong section etc.), it is my first post in this forum.

Now to the point. I found similar thread on this forum yet my problem is a bit different. When I turn on the amp I can hear a little crack on both channels, therefore speakers are receiving some signal, however only right channel is working correctly. Left channel stays quiet until I crank up the volume to cca 11 o'clock which is really loud. Then both speakers are equal and everything is fine. Also if I unplug right speaker I can hear that the left one is playing music from cd player but it is VERY quiet.

Now I will describe what I did so far:
Checked all transistors on the output board, all of the output transistors are ok. Checked fuses, diods and all other transistors... everything fine. Then I moved to volume control / input selector board. Checked capacitors, couple of those smd transistors . Switched couple of those ICs which are right next to volume knob (yes I have SMD rework station) to see if different range of volume will start working but no luck... still same problem and at this point I am clueless. Is it right to suspect Z86E21F1 on HA7A control board ?

And also I was not able to find schematics for HA7A only for HA7Z :/ That is why I am running around with multimeter and going trace by trace, shooting blind what could be wrong.

I've already spent couple of days trying to diagnose this amp but at this point I am stuck and dunno where to continue or what to suspect, therefore a bit of help would be appreciated 🙂

Oh, and I am also using PSX-R alongside with Cyrus 3 but that one is fine. I "unmoded" the amp for just the wall plug but problem preserved. Then I switched back to PSX-R configuration.

Thanks in advance for any suggestion.

P.S.: if you guys will need more tech info please let me know. I don't have the amp on my hands right now (writing this from university), therefore I was not able to write which exact components I checked etc.

P.P.S.: Sorry for any grammar error... I am not native English speaker.

Hello guys, I’m desperate to find an original power supply for this amp. It was handed down to me and I listened to it all the time but my partner threw out the power supply by mistake thinking it was for the keyboard we were getting rid of!!! 😡

If they are pure unobtainium would anyone happen to have a circuit diagram or know how to make one?? I have done a little research and there isn’t much online wrt the power supply. What I did find is what it needs a 19v+/- ac supply.

Any help would be much appreciated.

Matt

FE83En sound is nice vocal.










FE83En sound at YouTube
YouTube Live Test-FOSTEX FE83En at 2.5 meter(Logicool C270n HD Webcam、PC、TASCAM 102i、AKG P220で配信) - YouTube

I just happened to be looking around at audio websites during the last few days and noticed that some new models have appeared at Audio Nirvana since I was there last. Most noticeably the 'classic' line has expanded to include 12- and 15-inch models, in both ferrite and alnico versions. In addition, there is now a whole range of 'horn' models that have very unusual cones, as if a horn was built in. I haven't looked at that website for a year, but I can't find any comments on these models so I'm wondering if these are actually brand new and no one's noticed? I'll provide links to the T/S specs to save everyone from navigating that impossible site. 😉

http://www.commonsenseaudio.com/an10classicalnicospecs.jpg
http://www.commonsenseaudio.com/an12classicspecs.jpg
http://www.commonsenseaudio.com/an12classicalnicospecs.jpg
http://www.commonsenseaudio.com/an15classicspecs.jpg
http://www.commonsenseaudio.com/an15classicalnicospecs.jpg
http://www.commonsenseaudio.com/an8hornspecs.jpg
http://www.commonsenseaudio.com/an8hornalnicospecs.jpg
http://www.commonsenseaudio.com/an4hornspecs.jpg
http://www.commonsenseaudio.com/an3cfspecs.jpg

What is the final solution for anti-pop during power-on AND power-off on these boards?
I've read more than a few threads searched on google and using DIYaudio search engine. Nothing seems like the final solution during power-on AND power-off. The cap/resistor/schottky diode solution seems to work during power-on only.

Don't mean to beat a dead horse here, but hopefully future google searches will illuminate this thread as the final solution after we get some good responses in here from current owners/DIYrs. Thanks!

Four new, unused Jensen Mic Input Transformers JE-115K-E (note: theses are the previous version to the current Jensen JT-115K-E, current price $73 each). Build a high quality mic pre with these, an NE 5532 IC, and a few resistors and capacitors.

I would like to sell all four together. Asking $100 for the four, including shipping to the US.

Please PM if interested. Thanks.

11/26/2020 ***SOLD***

“Hans: An eye for an eye leaves the whole world blind, I believe that wholeheartedly.
Billy: No it doesn't. There'll be one guy left with one eye. Hows the last blind guy gonna take out the eye of the last guy left, who's still got one eye! All that guy has to do is run away and hide behind a bush. Gandhi was wrong, it's just that nobody's got the balls to come right out and say it.”

Before someone takes out my eyes, I want to build a speaker so when the eyes are gone, I will have something to listen to instead of chasing the guy behind the bush blindly.

My first post here. So, not sure if this is the right place for this question.

I wish to build a bipole mltl speaker using full range speakers.

Late last year, I came across few DIY speaker designs and I was impressed with it. Furthermore, I am also impressed by the design of Apple Homepod and Sonos Sub desgin. So, I went ahead and build one small bipole speaker using cheapest that I could find locally, Dayton PC105 4ohms (PC105-4 4" Full-Range Poly Cone Driver - Dayton Audio) driver, two of them in one box mounted back to back. Initially, I went with sealed cabinet but than ended up drilling a large hole and put a bass port, and I was impressed with it. Bass went lower than what the specs said and what I expected. It is nice and punchy and clean. No lingering boominess. Well this was speaker made by what was available, no measurements or calculations were used to design the cabinet, just went to hardware store and asked them to cut a long plank in 5 equal parts for 4 walls and last part cut in half for top and bottom. Anyway, it was a good outcome. This leads me to building a proper calculated speaker cabinet with better drivers but 4 of them in one cabinet.

So, what I am looking to build is...

A bipole speaker with 4 drivers 2 in the front and 2 in the back in MLTL cabinet for better bass.
The reason I went for fullrange is to avoid any crossover designs as I am just getting into DIY and want to reduce any complications. I would prefer to use 4 small drivers (3" or 4" inch) instead of mid woofer and big woofer for bass extensions.

Any suggestions on drivers to use. Any suggestion on speaker cabinet designs and cabinet measurement calculations and etc. What about the power requirement, I assume using 4 speakers in one cabinet will require more power.

Appreciate your help.

Hi all,

I'm building speakers with 3 drivers (treble, mid, bass) and bass port.

There's a multitude of info. here on various x-over designs, I'm looking for a passive system with linear response that might be avilable as a kit or at least based on an existing PCB. The speakers will be ~150w, 8 Ohms.

Words mentioned, I've seen 'eliptical' plus various 'orders'...

Any takers?

See my Audiogon ad. $1250 plus shipping.

Rare class T (switching class D) Tripath-based amplifier.
Excellent sounding amp. I have moved to a Class A stereo amp, so I am parting with this one.

I purchased it used from a hifi shop. It was advertised as from a non-smoking home and I also live in a smoke free/pet free home. Very clean with no marks on the face plate and very good top and sides and rear (see pictures).

It has served me well and I am certain you will be happy with it.

The 150.2 produces a strong 150 WPC into 8 ohms, and 300 WPC into 4 ohms. BAL and SE inputs are provided, along with a 12V trigger and detachable A.C. power cord.

Like the 150M, the 150.2 produces very little heat because of its high efficiency, so it is ideal for in-cabinet installations.
International buyers will pay actual costs for shipping

Hi all of you.
I bought 4 Scan Speak 15W/4524T02 at 4 Ohm. I am building a two bookshelf boxes with 2 mid woofers and one 8 Ohm tweeter. Should I just double the box volume designated for one speaker and should I just double the port area and keep the same length?
Thank you in advance.

The pandemic has left me with a backlog of 12 drivers which need surrounds. Normally I am quiet fearless about such things but all 12 are vintage drivers which need to turn out well. 4 of them are bentrene (polystyrene) ESS drivers. I have not shimmed before. Advice? Good shimming videos? Specific experience with bentrene drivers? Thanks

When you bridge an amp normally you feedback each branch individually and it gives what it gives. This type of error corrector acquires differential output and provides correction on one side only. To show how effective it adjusts, I take a VAS stage of gain +/- 5 on each branch to drive a nonbiased low quality pair complimentary transistors. One side receives directly the input where the inverting side receives corrected signal.

With 10v output I get a distortion of 0.04% with 10khz and perfectly stable.
The result is superior with AD8008.

Hayk

The pandemic has left me with a backlog of 12 drivers which need surrounds. Normally I am quiet fearless about such things but all 12 are vintage drivers which need to turn out well. 4 of them are bentrene (polystyrene) ESS drivers. I have not shimmed before. Advice? Good shimming videos? Specific experience with bentrene drivers? Thanks

I've had a pair of Epos ES12s for a number of years, and always loved them.
Recently bought a second pair for my girlfriends cabin, along with the stands.
The seller stated that he had replaced the front baffles/mid drivers a few years back due to rot. Figured, great, already replaced and newer-ish, well cared for.


When I got them, I noticed the speaker was totally different Epos molded unit, composite I think.


Attached is a photo of two different baffles: the newer one in the foreground and the 'older' one from my ES in the background.



The newer one is much larger, but feels to be same weight and stated specs. The rest of the baffle is exactly the same.



Anyone have any ideas the differences in sound, is the newer much better than older? I am afraid my set up and space don't lend to really tell a large audio difference, but it sounds as if the newer ones are.....cleaner, sort of? Brighter? More detailed but slight sound of tin can compared to my older ones.



Thank you!!

So, I run a sound company that hugs the line between DJ work and the corporate/live sound world. I've also learned if you have time & money, it's wise to spend what you have most of, and due to the Covid thing, I obviously have more time. So, I've spent most of this year building speaker cabinets & gear racks in anticipation of the day they actually can get used.

Just like everyone else though, my business isn't making the $ I thought it would this year & 'adapting to the new environment' instead of waiting for the environment to get back to normal is what seems necessary lately. I've been analyzing through what aspects of my company could make money on their own, because there simply aren't any audiences to put a PA in front of lately.

Anyway, I have 2 different ideas that I believe would work:

#1 Buy/build a CNC setup: Put it to work making knockdown cabinet kits for DIY kinds of people. That machine could also (possibly) source work from our local construction industry, and maybe make artwork for Etsy or something like that. Also, it makes sure the audio side of my company has a bottomless supply of speaker cabinets, I'd just have to buy drivers & amps 🙂

#2: Spraying U-Pol Raptor (or similar): This is the goop I've been spraying my cabinets with, and it's actually a DIY bed liner for pickups. Pretty sure it wouldn't be difficult to post a few pics online & get the phone ringing to refurb speaker cabinets, car sub woofer boxes, jeep bumpers, tool boxes & whatever else can fit in my limited spray space. I'd shy away from full vehicles & pickup beds though, I don't have the space & there's other shops in town that are better set up for that.

The CNC idea would require some $ investment on my part and time to get going, but it wouldn't necessarily be limited to local business. Shipping could make it workable for people all over the countryside. It also doesn't require a ton of my time once the machine is cutting up a job.

The idea of spraying Raptor has basically no barrier to getting it going, other than the willingness to do it. It also has the downside of it wouldn't make a nickel without me actually doing the work, where the CNC idea can to an extent. It also would be limited to a more local market I'd imagine.

So my question is this : Which way would you focus your attention on? Do you see another idea I've missed?

Thanks in advance!
Todd

Hi,


some resistors in tube amplifiers need to be able to handle some higher wattages, as you know. Is there any reason, why I shouldn't combine resistors to increase their max. power values? Or doesn't this create any difference or dangers and I don't have to buy the whole range of high power resistors of any value to be able to experiment at home without waiting for ordered parts all the time?


Thank you!


poppy

1.1" (29 mm) Soft Dome Tweeter

Bold North Audio Releases Soft Dome Tweeter Completely Designed and Assembled In America | audioXpress

Its nice to have a tweeter that is built in the USA. The price also seems to be reasonable, compared to the European ones. The manufacturer claims that this tweeter can be used down to 1kHz. Do you think that we really use this tweeter down to 1kHz using a passive crossover?

Bought a pair of these Dutch Masters from the local classifieds and, well, discerning audiophools best look away now, I stuck them in the worst enclosures thinkable. That's right, just some cardboard removal boxes. Yes, it's a bit like drinking a vintage Claret from a plastic cup (something I may or may not have done in the past...), but cheap and cheerful fun.
IMG_7688 by ctjr, on Flickr

IMG_7690 by ctjr, on Flickr

The verdict? These drivers have a very special sound all of their own: excellent drivers, not exactly neutral sounding but very nice for the stuff I like to listen to (and more besides). The soundstage is huge, the imaging is good too and, surprisingly, the speakers are hard to locate when listening with closed eyes. These speakers have no right to sound this good under these circumstances, yet here we are. The cardboard boxes act like a slightly undersized leaky box (just like many historical enclosures were build for these drivers); a very promising direction to look when it's time to build them some proper cabs

Bass, obviously, is not earth-shaking, but with floor coupling and room modes in a square 4x4 m, the bass is very, very acceptable. I ran a few frequency sweeps and the drivers comes in at around 40-45-ish (just like it says on the tin) and already produces quite a credible sound at 60hz. Nothing earth-shaking, but then again, that's neither useful nor desirable in a small city apartment build before sound proofing was a thing.

Anyway, lots of interesting possibilities with these drivers, they're definitely keepers.

Check this out: So as you can see, the far speaker is toed out while the near one is toed in significantly more than the other is toed out. My point is this is where they have to be to project a perfectly coherent sound stage where they disappear and only the music remains. 1/8" deviation by either and the image disappears. Very strange. I stumbled on this positioning while incrementally toeing them further out. I was not paying attention to symmetry but rather that they faced my listening chair at the same trajectory which is a bit off to the left of center. I knew this. When I adjusted them to zero toe in/out since they were so close and moved my listening position to center, it ruined the image. Is it possible my listening position is coincidentally exactly where the room acoustics place the sweet spot relative to where the speakers are located? These are Acoustat Monitor 3 ESLs. Both are exactly the same geometrically with no defect. I suppose my question is..can the room dictate speaker positioning regardless of symmetry?

Hi Everyone,

It's been a few years since I did much electronics diy, or posted on the forum, but I've recently been doing more, including the kit from the diyaudio store of Nelson's new crossover; I'm also planning a new FW amp build, maybe M2X, maybe F3, to use with it.

Searching out parts I came across a big toroidal transformer from a surplus site, which was cheap because it had few markings. I bought it on impulse, thinking I might need to rewind secondaries and that they might be fun (at least once). However after checking it out I'm wondering if I might be able to use it without doing anything. I've attached a couple of photos below.

It was sold to me as 1000VA, but I doubt it's as big as that. It weights about 11 or 12 pounds, is 5.5 inches in outside diameter, and about 2.5 inches high, so judging by this and other sites on the internet (like Rod Elliott's ESP site) it is more likely be between 500VA and 800VA. Which is still pretty big.

The side I presume is the primary (black/brown/white) has dual windings, each measures 2.6 ohms across black/brown, 2.2 ohms between black/white, and 0.6 ohms between brown/white. (This doesn't add up, but my meter may not be perfect, of course. Or maybe it's to be expected on a transformer.) The other (presumably secondary) side has four windings, all measuring the same, higher resistance. (Can't remember the value without checking.) Two are red/black, two are yellow/orange.

I tested it with a small AC voltage and then scaled up slowly. It turns out that if I connect the two primaries in series then each secondary gives slightly below 18V, which seems close enough. I used a modest load - can't remember precisely - so there was a reasonable current draw.

The plan is to wire the primaries in sequence, with a CL60 between them, as Nelson shows in his article on several FW amps. 110 V on this side, from the wall. Each of the secondaries would have its own rectifier bridge, and then all four would connect in parallel to a filter. With a little luck a big CLC filter, but that's not really relevant. (Although I note that in a thread of mine from a few years ago AndrewT said when secondaries are "bifillar", whatever that means, you can wire them in parallel to the same rectifier.)

So here are my questions.

1. Is there any reason to think I have it the wrong way round, and this is some sort of transformer to scale low to high voltage? Doesn't seem likely - just thought I ought to check. The "primary" side has the clips shown in one of the photos, if that helps.

2. I doubt I'm proposing to wire the primary side the way it was intended. I don't think this makes any difference, does it? 110V on the primaries in series will produce half the voltage in the secondaries that 220V would, which was presumably the idea. So as long as I don't draw more current than is safe then there should be no problem, right?

3. What would the purpose be for the off-center tap on the primary side? I'm not planning on using it, but I'm curious.

4. Any reason my plan for using this in a stereo FW build wouldn't work? If so, is there any advantage to wiring the secondaries in some other way than what I propose?

Thanks in advance for any input.

Best

Nigel

I have some 3 way towers that I would like to convert to 3.5 way actives. Any recommendations for DSP to use? My receiver's pre-outs and my amplifier inputs are un-balanced RCA jacks. I don't have a computer connected to my system and I don't want to add one. This is for home use in my living room. Here is what I'm considering.

freeDSP Aurora - I like it the best, but I have to pay for shipping from EU, I will need to add a lot of parts and time to make it work. The analogue inputs and outputs are balanced so I might need to add buffers to make it work with my un-balanced equipment.

MiniDSP 8x8 HD - Has everything I need but there is no way to access the DSP directly with Sigma Studio. This might not be necessary, also I see some posts saying miniDSP products have low quality ADC and DACs, not sure how much this matters in the real world.

2X miniDSP 2x4 HD - A little cheaper than the 8x8 HD, but managing two devices might make paying for the more expensive miniDSP a better solution. Same pros and cons as the 8x8 HD.

Something else?

Choosing the final parts I need to order for my SSE and working out pricing for various OPT options. One thing that really makes a difference is shipping charges.

I stumbled upon some relatively ugly 5k into 4/8ohm OPTs on ebay from China. They are described as "8-10 watt" and the specs match up approximately with the Transcendar 7 watt units and they are close to the same size as the Edcor XSE 15 watt units but the Chinese ones have a considerably thicker stack (35mm vs. 27.7mm). I have determined that 4-5 watts is about all I need 95% of the time.

I've made an offer on them and if it is accepted I will end up with two of them for $60 CAD including shipping. For comparison, the Edcors would be more like $130 CAD including shipping.

Believe me when I say, I do not have any expectations whatsoever about these OPTs. I know George stated on his site that people are unlikely to upgrade OPTs so they should buy what they really want the first time. Well, if these OPTs are crap, I will have no qualms about pulling them and upgrading to Transcendars.

This is basically just an experiment, with the benefit that it will expedite my ability to build and bench-test my amp. I'll update this thread when I have some experience with the OPTs.

What might cause noise like this? Class D amp.

Can't hear it on monitor speaker, just wondering?

Hello!

I am building a simple, cheap-o sub, something to cover the 35-100 Hz bandwidth. I am using the following speaker, Onkyo W20170A:

8 inch
Qms: 3
Qes: 0.372
Qts:0.331
Fs: 39 Hz
Vas: approx. 59 liters
Power rating: 30 W

I have placed it in a ~33 liter enclosure, with a 7.5 cm diameter vent, tuned to 35 Hz. Earlier it was tuned to 28 Hz, but there was a significant loss in power handling. Now I have tuned it to 35 Hz, there is an enormous hump (audibly) on about 33-34 Hz, and a huge loss on everything between 38-53 Hz.

Given the low Qts, should I tune it higher, like at Fs, or is there another issue? It seems what's happening is what you call "loss of headspace" for the bandwidth between the vent resonance and the -3 Db point at 55-60 Hz. Ideas?

Thank you in advance.

Hi,

I'm looking for internal photos of the DAB module that's inserted into the back of the DRA-700AEDAB AV receiver. The service manual sadly doesn't include the DAB module's circuitry. If anyone has the schematics for the DAB module, that would be even better.

Thanks so much in advance!

Sven

Looking for a pair of the BEX4008 or 16, if anyone is looking to sell. Thanks!

Hello all,

I'm thinking about linear power supply improvement.

Rectifying 3 phases transformer is better than single phase one because we obtain quite DC voltage without any smoothing. So if we use 3 phases transformer and then smoothing capacitors, the ripple quality will be far better than single phase version.

The problem is that in domestic use, we have only access to single phase AC.

What do you think about the usage of a Variable Frequency Drive (VFD) unit to transform single phase to 3 phases AC before supplying a 3 phases transformer ?

Another benefit could be also to increase the frequency of AC lines (up to 400Hz ?) in order to reduce more the ripple with same amount of smoothing capacitors.

I know that VFD generates shopper DC but do you think that transformers could handle that and smooth the current to have sine wave current at secondaries (as AC motor) ?

I thought I could just send a DM/PM to a mod, but that option doesn't appear to exist...

By which let me clarify, to include eARC from my TV, Airplay, HDMI input for a disc player, remote volume control, and room correction. And hopefully not spending a billion dollars.

I want to run a system of fullrange very efficient 2-way woofer/horn combos, maybe needing subwoofers and therefore possibly 5.1 bass management, and something like Audyssey/Dirac to fix the high frequency response droop of constant directivity horns. My default and seemingly cheapest idea is an AVR with preouts, AVR powering woofers and DSP amps powering the horns, the DSP providing highpass crossover and time delay versus the woofers. This is a little kludgy as it makes an extra A/D-D/A step.

I know miniDSP (and I presume others) make a variety modules. But is there any way to really do what I want without buying a expensive AVR or pre-pro? Or might I just as well stick to my kludgy plan?

The earpads for these headphones are smaller than what is commonly listed on eBay. They are 2.5"W x 3.12"H.

Where is a good source for Sony replacement pads?

I've been toying with the idea of building a 3-way speaker based on Troels Gravesen's CNO GRANDE design CNO-GRANDE for some time now. Why not build the CNO Grande you ask? Three reasons basically. Because I want to use some drivers that I already have on hands, because I'm not interested in overpaying for the kit from Jantzen audio, and lastly because the crossover values were not made public, so I'd have to reverse-engineer it anyway.

The CNO Grande is using the following Seas drivers: two W18NX001 woofers, a modified Seas W12CY0003 mid, and a T29CF002 tweeter.
E0042-08S W18NX001
E0044-08S W12CY003
E0040-06 T29CF002

Here is a link to the modifications to the mid driver: W12CY003

I'm guessing it's a few coats of surround glue applied with a brush, with the driver sitting on a low rpm turntable. I'll be doing these modifications myself, monitoring the results via measurement.


My design will be using the following drivers: two Seas U18RNX/P, a modified W12CY0003 mid, and a Morel ST728 tweeter. I'd get the enclosure professionally built, I simply don't have the time, space, tools, nerves or skills for that, sadly.

http://www.seas.no/index.php?option...e&id=102:h1571-08-u18rnxp&catid=44&Itemid=461
E0044-08S W12CY003
https://www.morelhifi.com/product/st-728/

Why this selection?

I currently have a TQWTL running the U18RNX/P and ST728 combo (factory matched tweeter pair), so I already have like half of the drivers.

And I'm convinced that the U18RNX/P is a better driver than the W18NX001 (W18 in black, U18 in red, matched sensitivity; look at the FR spikes in the W18 graph).



The ST728 looks better too. In my current 2-way design it has astonishing, near-constant directivity, resulting in a rock-solid stereo image. (T29 in black, ST728 in red, matched sensitivity)



I tried to model the crossover in VituixCAD using traced SPL and impedance curves, which are attached with this post (CNO_clone.zip). This is what I have come up with so far (XO points at around 1kHz and 4kHz, notice the 21mm setback of the tweeter):





I'm not sure I like the group delay and phase response.

I realize that the simulated response is not going to match the real-world, nor the in-box response, and much less the in-room response, but I have to start somewhere. The modifications to the W12 aren't taken into account either, obviously.

Now on to my questions:

How should I go about translating the simulated crossover into a real world build? I have a UMIK-1 and REW, so I can make basic measurements, although I have yet to spend more time with it.

Does the crossover topology make sense for my driver choice? Any criticism is welcome.

I really hope to get a discussion started, so any input is welcome.

I've already started building a small sealed standmount mtm, similar in layout to the old AE-2 but w very tightly grouped drivers. I'm using a small format tweeter and 15W rev's.
Any issues with the midbass drivers being so close, 1cm gap? Ie vertical sweetspot.

Q150 Bookshelf Speaker | KEF

Going to remove the drivers and XO to put together a rather tall MMUMM with 6” woofers and an active filter from woofers to the UniQ.

Will post some measurements once the Kefs get here and I get them apart.

On request here’s the builders thread for the assembly of the Inverted J-FET Circlophone.

The Inverted J-FET Cirlophone PCB was initially strictly intended for personal use only, but after several private requests over time I decided to make it available for the DIY community.

The component placement document (PDF) with reference designators matches the schematic.
The silkscreen (component) values on the inverted J-FET Circlophone PCB correspond with the schematic and are all correct, but the reference designators DO NOT match the attached schematic.
Cross-marked components without component values are ONLY for experimental use and/or a different outputstage configuration.

Highlights of this version:
Scalable outputpower, rails up to 50V
JFET input, (virtual) absence of gate/base modulation
Improved step response of the CFP configuration
Reduced phase inverter dissipation
Original Circlophone features:
No (very low…) cross-over distortion, semi class A
No need for thermal tracking the output devices
Idle current 200 mA, Gain : 28 dB

Long shot here, but I'm in need of 2 power transformers, one for a 222C and the other for a LK-48. As it works out, they're both basically the same power transformer. I have one of each amp here in my home for repair / refurbish, and neither even have the old 'dead' PTs on them. So, I don't even have a decent core to send in for a rewind. As such, I'm looking for 'dead or alive' units. ANY help here would be greatly appreciated! Many thanks!!

Tom D. - Wharfcreek@Outlook.com