"WHAMMY" Pass DIY headphone amp guide

[cyc1994622]

Hi, can someone give me some advise on the thickness of the wire connecting ac to the board.

i am looking for solderable C14 iec inlet with switch, and i found this,
4304.6079 Schurter Inc. | Connectors, Interconnects | DigiKey
is this good or is it a overkill?

 

[6L6]

The inlet module is very nice!

Wire gauge required is more a function of length than anything else, if less than a foot 18ga or even 20ga would be fine. Use what you have, and you can always double it up if you are worried.

 

[wayne]

I tried the OPA2134 and it works fine just don't use the 100 pF caps.

 

[mbedwani]

I tried the OPA2134 and it works fine just don't use the 100 pF caps.

Thanks @wayne much appreciated.

I assume we still use the 22uF c26/c27 caps for this opamp?

Mark

 

[wayne]

Yes still use the 22uF. The FQP3P20 3N30 combination and LM833 are what I am listening to now from a Raspberry Pi with a Pi-DAC+. It makes a good little music player on my desk with a pair of SR325.

 

[msikk]

Complete - Sounds Great!

WHAMMY complete and sounds amazing! Thanks to everyone who worked on this project! Now on to the Aleph J...

 

[cyc1994622]

The inlet module is very nice!

Wire gauge required is more a function of length than anything else, if less than a foot 18ga or even 20ga would be fine. Use what you have, and you can always double it up if you are worried.

thank you very much for the reply. unfortunately digikey and mouser are not providing free shipping unless i have spent enough in the place I live so that means i need to plan everything ahead.

 

[erix]

This is a nice project, great presentation, and thorough documentation. Thanks to all who pulled it together!
I’ve a couple of questions:
Ever try an OP275 in the opamp position?
Can the opto-biased source follower stage operate stand-alone, without gain?

 

[wayne]

Haven’t tried the 275 but the output stage will work stand alone that is the beauty of it.

 

[jphabc54]

Would the TKD 2CP-601S make a decent upgrade for the pot?

TKD Potentiometer 100K 2CP-601S Series 6R25 Log Taper Stepped

 

[Zen Mod]

100K is too much

10 to max 25K

 

[heijnsva]

I bought a 50k pot. I saw it in one of the BOM's in the other thread. Am I in trouble?

 

[Zen Mod]

not so much , as with 100K

relax , majority will not hear the difference between 10K and 50K

(that's exactly one of the reasons why I hate BOMs ; it's always better just looking at schematic and using own brain)

 

[promitheus]

not so much , as with 100K

relax , majority will not hear the difference between 10K and 50K

(that's exactly one of the reasons why I hate BOMs ; it's always better just looking at schematic and using own brain)

Why is 100K too much?

 

[jwjarch]

Schematic says 25-100K. My ALPS 100k just arrived from China. Please tell me I don't have to wait another 3+ weeks for another one.

 

[Zen Mod]

when introduced between source and amp circuit itself , pot is becoming source to amp

that means pot's own output impedance is thing in the game

lower , the better

in most critical position , Rout of pot is approx. 25% of it's nominal resistance , so better to have 2K5 as source Rout , than 25K

go figure

aha , one thing more - with 10K pot , interconnect cables are much less important players in game

 

[jphabc54]

Thanks for the tips on the pot. Would implementing a 10k pot require changing any other components? Similarly, do people think the 10k TKD is a worthwhile upgrade to the ALPS?

TKD Potentiometer 10K 2CP-601S Series 6R25 Log Taper Stepped

 

[wayne]

All the units I built used the 100K Alps mostly because they are 10 meters away in the stock room. The TKD is pretty nice not sure I could tell the difference.
You can use a 10K with no value changes it would be less noise sensitive.

 

[Ultrasparc]

Almost complete, Need to tidy up some metal work, add a volume knob, and add a Headphone jack. Sounds very nice driving my A40. A big thanks to Wayne, 6L6, and alexcp (who sold me the board).

 

[promitheus]

Hi, can someone give me some advise on the thickness of the wire connecting ac to the board.

i am looking for solderable C14 iec inlet with switch, and i found this,
4304.6079 Schurter Inc. | Connectors, Interconnects | DigiKey
is this good or is it a overkill?

Those are very nice. I have used before for a power amp.
Its not overkill. You also have a power switch and you only need one opening for everything.