My first project SE(T) into high end audio.

[50AE]

The moment I dreamt of since last year came. My high end audio system and amp.

It starts from:

Optimized PC with XP OS, almost no fans, using CmP+Cplay -> 2496 AK4396 DAC unbalanced by E88CC Tungsram and 6N6P -> OFC interconnects -> SE(T) still on boards -> CapryNatty horns



This is the schematic I started with. Using 6N8S insteand 6SN7GT and 5Z4M as rectifier.

System



Then progressed to this:

Schematic



Then to this - the sound was getting better and better.
Schematic2
Amp



Few days after trying DC for the 6B4G's filament, because I couldn't defeat the hum, I tried 6P45S in triode mode and this is what my system looks like now.

Schematic3
System

I've been modifying it since.. Can't really remember, but a month or two. Every mod I did has improved the sound. I've been changing PSU caps, coupling caps, cables, tubes.
The DAC schematic is "the unbalancer itself". The OPT very high quality custom made. Tubes are NOS. Power transformer and output stage choke from DragonPriest audio, driving stage uses russian NOS chokes DR 5H-0,08A. The DAC tube PSU has separate filament transformer. It has a rectifier for each channel and then C LC LC LC filtration using PIO bulgarian caps and 5H russian chokes.

The coupling caps for now are PIO - Jensen, KBG. KBG is a very elite russian PIO capacitor. I've tried K42-U2, K40, K75-10 and many others. K75-10 is great also btw.

My amps are still on boards because I find it fun to learn and experiment with every new component I get.

[50AE]

This is the current system schematic, modified and the sounded is very improved. The most stunning improved was done by changing the coupling cap from KBG to Bosch MP. Power supply caps also improved stuff. DAC direct coupling and changing the DAC regulator resistors from wirewounds to metal film did a huge difference.

http://store.picbg.net/pubpic/BC/E2/...275080bce2.png

Edit: forgot the grid resistor, which is 200k

Current photos of the system:

Dark

Lights on

[disco]

PICBG is offline it seems...

Do you consider a computer a high end source?
I remember WAFs and AIFs as not top of the bill.
Things change of course

[azazello]

Looks good. To avoid hmmmm in schem. with 6S4S, You can rectify 6.3 v with filter CRC /10000uF, 1 0hm, 10000 uF/. My SE 6S4S sounds without hmmm in my
speakers Fostex206E- 96 db. /I prefer 6S4S, comparing to 6P45S/ E180F is very good choice / my favorite pretube/. I'd advice You use cathode caps for output tube BGate, ELNA, Nichicon instead ROE.

[50AE]

Sorry, did not have an idea that pic bg is offline for the foreign countries.

Currently, the schematic will be D3A + 6P45S + 5C3S or GZ34. d3A will have a 10m45S CCS at the anode. 6P45S will work in 300-330V-120mA, depending on the rectifier. No cathode caps or resistors. No electrolytic capacitors in the whole schematic. Power supply caps are PIO.

I will soon buy new output trannies specially made for 6P45S.

http://imageshack.us/a/img248/4683/picture040wk.jpg
http://imageshack.us/a/img231/8861/picture002mo.png
http://imageshack.us/a/img507/2968/picture003sm.jpg

I am currently working on the chassis and I'm about 70% done. Currently doing the veneering.

http://imageshack.us/a/img706/4927/picture032yy.jpg
http://imageshack.us/a/img849/4337/picture059d.jpg
http://imageshack.us/a/img842/7538/picture073nv.jpg

aazello, 6B4G might sound good, but I preferred 6P45S and it's more convenient for me - higher output power to match my medium efficient (92dB/W/m) speakers. Also I don't need to rectify the heater supply, the tubes are undirectly heated. There is not any hum in my system, just very slight when I stuck my ear to the speaker and it's from the smoothing filters.

[freax]

I love using http://www.imgur.com its far easier than using imageshack, you might come to prefer it too.

[50AE]

Thanks, I will try it.

Here are more links from the chassis work.

http://imageshack.us/a/img838/5646/picture050i.jpg
http://imageshack.us/a/img443/6898/picture048x.jpg
http://imageshack.us/a/img705/4238/picture055mb.jpg
http://imageshack.us/a/img849/4337/picture059d.jpg

What the amp looked like before http://imageshack.us/a/img713/9297/picture091l.jpg

[costis_n]

But if you are going to have a CCS at the anode, what are you going to do with the extra gain? I notice you have a 10K resistor, which gives low gain for d3a, so I would expect the gain to jump to a very high level. So you plan to add feedback maybe?

[50AE]

With a CCS, gain almost equals mu, right? My max input signal will be about 1,1V. Mu of D3A is 74. The swing the drive 6P45S in 300Va/120Ia mode is -75V.

1.1*74 is 81,4 gain. A little bit of extra doesn't hurt. It will help in fact, because later I'll increase Va and I'll need more gain.

With a little bit more of signal level, I could use E280F, which sounds orgasmic. 1,5V of input is enough for the E180F also.