[migo]

1. What is the CFA-3P?

Power version of CFA3

2. WIll Headamps CFA-3 be sonically superior to other's or same thing in a different chasis?

Every CFA3 is original one built in different specs and used components, so there may be small sound differences, but superior is not to be expected maybe a bit different.

 

[rsbrsvp]

I assume the POWER version of the CFA-3 is of no extra sonic value to headphones but only for speaker use.

Is this correct?

 

[migo]

I assume the POWER version of the CFA-3 is of no extra sonic value to headphones but only for speaker use.

Is this correct?

well, that is THE question! I'll try to find it out how it copes with Susvara.

 

[slazhx]

well, that is THE question! I'll try to find it out how it copes with Susvara.

Look forward to your finding, please!

 

[migo]

Look forward to your finding, please!

According to CFA3 specs and experts opinions there should be no difference for ANY headphones, and CFA3 is beefy enough for this purpose. But I'm curious and will try to go this route too, like @normie610

 

[slazhx]

I've been stalking you guys for quite some time

The more I read, the more itch I have ... but in a pleasant and torturing way at the same time ... haha

I almost pull the trigger with CFA3 from another member I trust, unfortunately, I'd just bought J2 by that time.

CFA3 will be the next project for sure. CFA3, CFA3P, CFA3 Headamp, Supratek DHT, Elrog 300B, ... oh man.

 

[rsbrsvp]

Does anyone think thick silver occ wire on the internals would make any difference in sound?

I asked this question to several technicians who have quite good reputations including Dr. Gimore, and all said- NO. As long as the impedance is correct, silver internal wireing instead of standard wire should be either inaudible or so close to inaudible that it would be ridiculous to do it. Any other opinions out there?

On the one hand- I am no technician and need to trust those who know better than me; on the other hand I can hear (perhaps in my imagination) big differences in IC and headphone cable between copper and silver, and palladium and wire thickness as well, and litz vs solid wire as well, so why should the innards of the amp. be any different?

 

[normie610]

According to CFA3 specs and experts opinions there should be no difference for ANY headphones, and CFA3 is beefy enough for this purpose. But I'm curious and will try to go this route too, like @normie610

Yep theoretically there should not be any difference in sound. However, with a beefed up spec, who knows it might bring better control over the headphone drivers and hence has a different effect on the sound, etc. The components Dukei is using this time around is also a bit different with my previous build e.g. Toshiba transistors, a combination of AN Kaisei & Nichicon caps (though not in the signal path so it shouldn't affect the sound but perhaps cleaner power), thick copper wire, etc. So maybe all these new elements plus higher power rating could bring something new to the table in terms of sound quality. Or perhaps not we shall see when the build is completed.

 

[migo]

Yep theoretically there should not be any difference in sound. However, with a beefed up spec, who knows it might bring better control over the headphone drivers and hence has a different effect on the sound, etc. The components Dukei is using this time around is also a bit different with my previous build e.g. Toshiba transistors, a combination of AN Kaisei & Nichicon caps (though not in the signal path so it shouldn't affect the sound but perhaps cleaner power), thick copper wire, etc. So maybe all these new elements plus higher power rating could bring something new to the table in terms of sound quality. Or perhaps not we shall see when the build is completed.

Exactly that! Output Transistors are Sanken, there are three pairs output transistors and higher rail voltage can be used.

 

[kevin gilmore]

there are lots of reasons to use pure silver in teflon wire.

solders real easy
when you make a bend, it stays bent.
can't corrode, and what micro thick layer of silver oxide is still conductive.
there is a reason why the us military requires at minimum heavily silver plated copper wire.

1 foot of sound, not so much.

 

[jlbrach]

well, that is THE question! I'll try to find it out how it copes with Susvara.

it is the same 15 watts into 50 ohms so it will power the susva just fine as mine does

 

[audioguru1]

Does anyone think thick silver occ wire on the internals would make any difference in sound?

I asked this question to several technicians who have quite good reputations including Dr. Gimore, and all said- NO. As long as the impedance is correct, silver internal wireing instead of standard wire should be either inaudible or so close to inaudible that it would be ridiculous to do it. Any other opinions out there?

On the one hand- I am no technician and need to trust those who know better than me; on the other hand I can hear (perhaps in my imagination) big differences in IC and headphone cable between copper and silver, and palladium and wire thickness as well, and litz vs solid wire as well, so why should the innards of the amp. be any different?

I have tried copper and then after trying various combos ended up with balanced parts connexion pure silver wire on the input side, and cloth covered copper on the output side. Silver does have different measured conductivity differences (elemental), its maybe? smoother and richer. Using all silver (input and output) was too much. The parts connexion stuff is one of the few silver cables that's not bright. If I were to build it again, I'm not sure I'd bother (especially at 11.50 a foot). I'd just use good quality balanced Canare wire. It doesn't make a major difference in sound, maybe the last few percent (i'm 100% agreeing with @kevin gilmore above). Also, (as some of us do to make it easy to service) the screw terminals we use are much lower quality than even soldered copper -- usually nickel (once I finalize my case, I plan to hard solder the last few connectors -- I just have them on the protector board). Ultimately I think voltages, bias points and electronics parts choice matter most. In my build, what I'd consider the most impactful choices were the actual transistors (eg matched NOS Toshiba input transistors, matched NOS Motorolla MJF outputs - which actually measure different), going with dual mono power supplies @24v (need to try 25v and 30v, and DNM guided current power supply caps) with each having a 250va toroids (complete overkill, but not much more expensive for me to source), Dale metal film output resistors, Audio Note Kaisei electrolytic caps (successor to black gates, and used in some of the Holo Audio stuff), and dual discrete Khozmo volume controls with remote (so I can adjust each channel) with amtrans resistors.

One case in point, we all have different systems and preferences. These are my choices, I make no claims about what is best, just what I did and liked. As much as I could I tried to get the absolute best parts and do some actual testing, listening, and swapping things in / out. I actually used a Audio Precision ATS1 (old with not as good precision as newer units, but still useful) as I adjusted bias (distortion keeps dropping up to about 215mv, but its summer and that was too much heat), it was also a tad rich sounding. I found 200 the best balance for my application. As is always the case your choices and mileage may vary.

 

[migo]

it is the same 15 watts into 50 ohms so it will power the susva just fine as mine does

Depends od PS used, can be configured much more than 15W/50Ohm.

 

[AndyDU]

decided to ask here as the other site is eerily quiet...

----

• What's the latest gerber file with both input and output? (filename should be sufficient
  
  
• what's the minimum voltage I can use with the amp?
  
  
• average power consumption? (or shouldn't even think about it considering it requires massive heatsink? )
  
  
• What's the difference between cfa3production.pdf vs cfa3productionss.pdf
  
  
• Kevin Gilmore posted a split board Gerber files. He only posted the files for the output section. I am not sure which one is the input section. I looked at the shared folder and I don't know which input section to use.

Thank you.

Hi, do you find latest Cfa3 Gerber files? Where? Andreas

 

[ScornDefeat]

Quick question for anybody who might know; does the (prospective) Headamp CFA3 have a pre-out?