100W Ultimate Fidelity Amplifier

well done,xrk971, I have a directory devoted to the Apex designs, incomplete I may add.
wish that this site/forum could have a means to create individual projects for proper sorting of documentation and related threads, I asked they did not consider my suggestions

Perhaps you can augment my post with your collection? PCB layouts, BOMs, photos of confirmed builds etc
 
You missed a few. Here is one off the top of my head.

A33
451846d1417544972-100w-ultimate-fidelity-amplifier-apex-a33.jpg
 
As this is a "living" index, we need to quote it each time we add to it, otherwise we will keep on having to go back and search. If Apex Audio could point to the index post from post 1 that would be helpful.

Here is an addition by Still4given for AX33...

Here is a collection of just some of the schematics from Apex Audio over the course of time in this thread. These were obtained from using the search feature and I am missing many but think it's a good start if others can add to this, and also add PCB layouts - use the quote feature so it is all intact. We can perhaps begin to use this as a "Living Index" to the profound productivity and good will that Apex has given us.

FX8 (50w) - uses lateral FETs:
347359d1367965695-100w-ultimate-fidelity-amplifier-apex-fx8sch.jpg


AX11 (50w):
342757d1366040499-100w-ultimate-fidelity-amplifier-apex-ax11sch.jpg


AX11TEF (50w):
536257d1457475704-100w-ultimate-fidelity-amplifier-apex-ax11tef.jpg


AA11 (class A):
537337d1457974999-100w-ultimate-fidelity-amplifier-apex-aa11sch.jpg


AX13 (50w?):
347374d1367973319-100w-ultimate-fidelity-amplifier-apex-ax13sch.jpg


AX14 (80w):
167581d1271628000-100w-ultimate-fidelity-amplifier-apex-kelvin-v2.jpg


FX14 vertical MOSFET (80w):
178830d1278159595-100w-ultimate-fidelity-amplifier-apex-fx14.jpg


NX14 NMOS amp (80w):
179301d1278422412-100w-ultimate-fidelity-amplifier-apex-nx14.2.jpg


AX15 (80w full symmetric amp):
246036d1319407815-100w-ultimate-fidelity-amplifier-apex-ax15.jpg


AX16 (80w):
179202d1278348376-100w-ultimate-fidelity-amplifier-apex-ax16.jpg


AX17 (80w):
246444d1319579956-100w-ultimate-fidelity-amplifier-apex-ax17.jpg


AX18 (80w):
246153d1319466566-100w-ultimate-fidelity-amplifier-apex-ax18.jpg


AX20 (120w):
246443d1319578391-100w-ultimate-fidelity-amplifier-apex-ax20.jpg


BX20 (w?):
536674d1457638070-100w-ultimate-fidelity-amplifier-apex-bx20.jpg


AX30 (w?):
519308d1450126875-100w-ultimate-fidelity-amplifier-apex-ax30.jpg


AX33:
451846d1417544972-100w-ultimate-fidelity-amplifier-apex-a33.jpg


AX40 (?w):
461233d1422093709-100w-ultimate-fidelity-amplifier-apex-a40.jpg
 
It may be of general interest in this thread - anyone making one of the larger amps, I have tested the Abletec 450w 53v SMPS with a class AB amp and it works very well. A nice PSU for $25 - can save some cash and weight for your next amp project.

http://www.diyaudio.com/forums/clas...ual-rail-450w-supply-20-a-12.html#post4732609

552527d1464763634-abletec-53v-dual-rail-450w-supply-20-vhex-amp-build-3-abletec.jpg


20mV ripple after passing output through a Dx PSU filter bank. It has 190mV ripple without the Dx PSU so the filter is needed to keep noise levels down.

If I used my newer CRCLC PSU, I think the ripple would probably be <5mV.
 
How does one use this "living" index?

One feeds it with pics, PCB layouts, and BOMs - or links to those items. It will grow with user participation. I managed to put it together in about an hour, just think if the 500 people reading this thread would contribute to it by adding links how useful it could be. Maybe there should be a Wiki for Apex amps and then we could indeed collaborate on editing and updating an index with diagrams, text, layouts, etc. For now, lets use this to collect content.
 
As this is a "living" index, we need to quote it each time we add to it, otherwise we will keep on having to go back and search. If Apex Audio could point to the index post from post 1 that would be helpful.

Constantly quoting a single post with tons of embedded images will make this topic even more unreadable then it currently is. Personally, I would leave topic management in the hands of original topic poster, Mr. Mile himself.

Oh, and you have missed quite a few of the CFA amplifiers in your list:

A9, AX9, A17, A23, FX9, A15, etc...
 
It may be of general interest in this thread - anyone making one of the larger amps, I have tested the Abletec 450w 53v SMPS with a class AB amp and it works very well. A nice PSU for $25 - can save some cash and weight for your next amp project.

http://www.diyaudio.com/forums/clas...ual-rail-450w-supply-20-a-12.html#post4732609

552527d1464763634-abletec-53v-dual-rail-450w-supply-20-vhex-amp-build-3-abletec.jpg


20mV ripple after passing output through a Dx PSU filter bank. It has 190mV ripple without the Dx PSU so the filter is needed to keep noise levels down.

If I used my newer CRCLC PSU, I think the ripple would probably be <5mV.

what amp is that and how does it stack up against fh9?
 
what amp is that and how does it stack up against fh9?

It's the VHEX+ and it also uses IRFP240/9240 like the FH9 but topology is completely different and it's twice as powerful as FH9. Can't really compare as they are like apples and oranges. The FH9 sounds just as good and has a similar MOSFET output quality at comparable power levels. The VHEX+ just has so much more dynamic headroom. It's a very nice design that uses SMT and through hole parts.

More info here:
http://www.diyaudio.com/forums/solid-state/286992-irfp240-9240-amplifier-simulated-tina-33.html
 
All that is needed is a periodic update of post #1 to point to the various designs.

I second this option. We don't really need the images in the post #1, just a list of designs, maybe short description and links. Like

FX8:
50watt, NPN differential input, complementary NPN/PNP VAS, lateral MOSFET output.
APEX FX8 post 2125, APEX layout post 6174
Prasi initial PCB layout post 6160, Prasi/Sonal edited layout post 6184
Bimo-mod version with simulation post 6483 using 2SC1845 input, 2SA1381/2SC3503 VAS, 2SK1058/2SJ162 output.
Prasi layout of bimo-mod post 7146

I hope Apex/Mile will consider editing the first post with some links for each design, but I understand it is a lot of work. Sorry I only have the information for the FX8 since that is the one I am building and studying, and I hope my understanding and description of the design is correct.
 
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It may be of general interest in this thread - anyone making one of the larger amps, I have tested the Abletec 450w 53v SMPS with a class AB amp and it works very well. A nice PSU for $25 - can save some cash and weight for your next amp project.

http://www.diyaudio.com/forums/clas...ual-rail-450w-supply-20-a-12.html#post4732609

552527d1464763634-abletec-53v-dual-rail-450w-supply-20-vhex-amp-build-3-abletec.jpg


20mV ripple after passing output through a Dx PSU filter bank. It has 190mV ripple without the Dx PSU so the filter is needed to keep noise levels down.

If I used my newer CRCLC PSU, I think the ripple would probably be <5mV.

I think you will all be interested in this development. I swapped over to the CRCLC PSU filter and the ripple at 51v with VHex+ amp is now 1mV! The speakers have never been this quiet before with no music playing. This is perhaps one of the highest value ultra low noise power supplies I have seen. SMPS is $25 on eBay and filter is maybe another $7.

A high value 50v class AB power supply that sounds great. Lighter weight than toroidal transformer too.
552738d1464831772-irfp240-9240-amplifier-simulated-tina-abletec-smps-crclc-psu.jpg
 
It's the VHEX+ and it also uses IRFP240/9240 like the FH9 but topology is completely different and it's twice as powerful as FH9. Can't really compare as they are like apples and oranges. The FH9 sounds just as good and has a similar MOSFET output quality at comparable power levels. The VHEX+ just has so much more dynamic headroom. It's a very nice design that uses SMT and through hole parts.

More info here:
http://www.diyaudio.com/forums/solid-state/286992-irfp240-9240-amplifier-simulated-tina-33.html

In thread http://www.diyaudio.com/forums/solid-state/162043-mosfet-amplifier-irfp240-irfp9240-47.html post #470 you can find nice and powerfull amp with IRF240/9240. and there is FX120 in thread http://www.diyaudio.com/forums/solid-state/162081-dc-servo-mosfet-amplifier.html ...
Regards