[Tomo]

Hello,

Before anything please forgive me for keeping your soldering fingers warm and itchy. I really did not mean to leave you in wonders. Our FTP server went down and I could not upload to our website server. Anyways, it's fixed. (And, I was working my butt off at office. ...)

So here it is my latest Szkeres amp.

As usual, Hi-Rez for your dirty pleasures.

I would like to publicly thank vdubjunkie and Squalish for offering to host my picture.

Tomo

 

[Budgie]

Glad to hear you are still building Skeres amps. Have you made any changes since the original discussions at Headwise?

 

[MisterX]

Removed..

 

[Tomo]

Hey,

I have not implemented CCS. This is because it help when you use higher impedance models. However, I am exclusively building it for low impedance cans such as Grado. R4 is a silicon wirewound 5W 20 ohms. This is a high quality one from Dale (but not NS-5).

MOSFETs are now bypassed with Cerafine 2200uF (one per chennel). Ceramic caps are omitted in favor of the Cerafine.

Input coupling caps are now Solen 4.7uF. It is chosen because I have them in abundunce. I was going to bypass it by Siemen MKP 0.47uF, but the result show they are in fact unnecessary.

Output coupling caps are 1000uF caps with HFQ-level quality. (Don't remember the brand ... ) Each output coupling cap is bypassed by a pair of polypropylene caps (Siemen MKP and Solen).

The gate blocker resistor and the source resistors are extremely close the mosfet to reduce inductance near the mosfet. The rest of circuitry is kept very simple and short.

The board has two ground planes. I used one for ground and the other floating ground. The ground plain on the component side is floating.

No hum, no buzz. I can't hear looseness. This has wet/juicy and weighty sound compared to articulate and delicate sound I get from THS4022 w/ K240M. Because of this, the amp is very accomodating to poor quality CDs.

T

 

[Tomo]

Hi,

Dark? Well I am kinda impressionist and like "dark" pictures associated with post-renessance period artist such as Goya.

Anyways, can you pump up your backlighting on ya monitors?

Please PM me if you are having the same problems.

T

 

[ofb]

thanks for posting a pic, and yes, dark indeed. looks like you're using a scanner? i found that some units will have reduced vermeer if you use a black backing paper.

 

[Tomo]

Fixed.

Ain't it beautiful?

I forgot to mention the fact that I have changed biasing. My calculations show it is still very far into saturation regime.

I think this is very sweet sounding amp. And, it is full blown Class-A. You can't get anymore Class-A than this. Provided you pick right caps, you can get reference quality sound. I think I am going to get me Grado Cans sometime.

Considering the quality I get out of it, I think Szkeres amp is an excellent candid for low impedance headphones. (Perhaps even better choice than opamp based designs for low impedance cans.)

Stopping at META-derivatives would be a shame, methinks.

T