Current feedback headphone amp

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
Jump to Latest
peranders

peranders

Member
Joined 2002
sjostromaudio.com
Paid Member
Originally posted by XELB I Liked the:

" Ultra high performance current feedback headphone amplifier with snuberized super power supply " :eek:
Click to expand...
Thank you guys but I discovered that I wrote snubberized on the pcb but it never got snubberized. Of some peculiar reason it sounds wonderful despite that :att'n:

So the right name is : DC servo controlled ultra high performance current feedback headphone amplifier with dual mono quadruple super regulated power supply"
 
peranders

peranders

Member
Joined 2002
sjostromaudio.com
Paid Member
I have listened to the amp the whole evening and it is really good, very revealing. It reproduces everything, shows no mercy. Noise, hum, noise gates, breaths from the people, noise from the instruments, everything is there wether you like or not. I'm not good with using a certain type of vocabulary but I could use: Spooky clearness, warmth, mint cool treble, mids with body, firm base, etc etc.

I wonder how much the super regulators do? It's hard to test the amp without them and I have no desire to ruin the pcb. I'm pretty sure that my discrete current feedback almost demands an ultra pure supply voltage due to it's rather low PSRR.

In anycase I'm extremely pleased with the results. I looks also very nice especially when it's switched on because of all red LED's.
 
jmd01

jmd01

Member
Joined 2004
jmd.szm.sk
Hi Per-Anders
Already I am wrote (post#30), you have nice works.
I am found some of

http://www.jmd.szm.sk/Audio/Measurement/CF_amp/CF_amp.html

with resembling results. In measurements get view a rest of PC and monitor (outside harmonic). Have view only for 2. and 3. harmonic, because work in A class. See even multiple 50Hz consequence imperfect power supply (only LM317 and 337).

Thank you for inspiration.


Best regards,

Bohdan
 
jmd01

jmd01

Member
Joined 2004
jmd.szm.sk
The first I hand made version QRV06 with modification to TO126. As I wrote, I wanted to improve parameters in area 50 Hz multiple and DC offset. SMD connection is very difficult to modify. Unhappy, but the only possible solution is to use air construction ( RC elements in supply and DC servo). Later I have came to realize that I didn´t have to have trobles, if I use so excellent stable power supply as you have.
My wife have bought me nice present for all my celibrations. Headphones HD650 by Sennheiser. After all the modifications which I have commited on my PCB, I have no courage connect to output my new headphones. That is reason why I prepare to do the second experiment with lower bias current (300ohm loads in class A), the same with TO126 on output.

Best regards,

Bohdan
 
peranders

peranders

Member
Joined 2002
sjostromaudio.com
Paid Member
jmd01 said:
Here is mearsurements PC card with long average sampling FFT, therefor is the noise lower.
http://www.jmd.szm.sk/Audio/Measurement/CF_amp/GEN.gif
You can not see PC monitor burst.
I have not digital camera at home.
I try to do something with it.

I provisory found:
http://www.jmd.szm.sk/Audio/Amplifier/amplifier.html
Click to expand...
I and some more people wonder if you really have done the soundcard measurement right? The values are 10 times better than the specifications and I myself think it's pretty fantastic with no harmonics over -140 dB. Maybe you have done FFT of the internal signal without going through the DAC-ADC chain? Nevertheless the specifications are very good even 10 times higher distortion.
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
Top Bottom