"WHAMMY" Pass DIY headphone amp guide

The Start of my Whammy!

The Start of my Whammy!
 

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The Start of my Whammy!

Those look great! As you, I had the option to orient the PCB in either direction (I actually designed the case from scratch with that in mind, nothing as good looking as yours, that's for sure!).

There were pros and cons for each orientation... in the end, I decided that having the Pot as close to it's original position with minimum wires (but I didn't solder it to the PCB) outweighed the pros of putting the PCB rotated 90°.

I'd be interesting in your reasonings to do it with the PCB "sideways".

Case looks incredible!
Rafa.
 
I just installed a 10K Aliexpress SMD stepped attenuator.

I did not know what I could expect from such a cheap part, but It's very very good.

Perfect channel matching, 10.03K left and right, and the intermediate values I measured match exactly as well. The build quality appears to be good, and it feels pleasant when turning. The turning resistance is just where I like it. Not harsh at all, nice and soft.

Volume changes are heard with very quiet ticks in the headphone. 21 steps are fine, I need no more control.

Hoe does it sound? Well, it's just not there it seems to me. I cannot see how there's a better attenuator tbh. Amazing for just EUR 12.

If this thing holds up, it's an absolute steal.
 
Last edited:
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Joined 2018
Paid Member
yeah - they're insane bang4buck

as I wrote before, only some grease inside and they're good for eternity

without grease - you can expect them fail sooner or later

Which part are you supposed to grease? I tend to just put deoxit on the contacts themselves, and potentially a tiny bit around the little ball bearings (on the ones I've seen). Hope I've not been doing it wrong lol
 
I've heard from Andrew Sparks (AKA Sparko) with Sparkos Labs. He has confirmed what I'm sure many of you already knew. The "naked" configuration is best when using discreet regulators.



Have you reached out to their customer support? If so, I'm curious what they may say here since I just placed an order. :)

Btw, as I'm typing this, I'm listening to my Verités on naked regulators without C8/C10 installed. This little amp is very impressive.
 
I just installed a 10K Aliexpress SMD stepped attenuator.

I did not know what I could expect from such a cheap part, but It's very very good.

Perfect channel matching, 10.03K left and right, and the intermediate values I measured match exactly as well. The build quality appears to be good, and it feels pleasant when turning. The turning resistance is just where I like it. Not harsh at all, nice and soft.

Volume changes are heard with very quiet ticks in the headphone. 21 steps are fine, I need no more control.

Hoe does it sound? Well, it's just not there it seems to me. I cannot see how there's a better attenuator tbh. Amazing for just EUR 12.

If this thing holds up, it's an absolute steal.

I can only agree with you.
I've been using these potentiometers for a long time (over 1 1/2 years) and the original old Alps 27 have no chance compared to that.
I couldn't hear any difference to my relay-controlled volume control, and I have never liked the large potentiometers with the external resistors.
So far I have found 2 versions of these resistance pots, one in a blue housing like the Alps pots, and one that looks like the cheap pots, without plastic, which I also like better.
 
I can only agree with you.
I've been using these potentiometers for a long time (over 1 1/2 years) and the original old Alps 27 have no chance compared to that.
I couldn't hear any difference to my relay-controlled volume control, and I have never liked the large potentiometers with the external resistors.
So far I have found 2 versions of these resistance pots, one in a blue housing like the Alps pots, and one that looks like the cheap pots, without plastic, which I also like better.

I’m intrigued. Can I get a link to these?
 
I’m intrigued. Can I get a link to these?
Just look in the bay for "SMD Stepped Attenuator" or "Step Volume Control SMD", it is a bit more difficult on Aliexpress.
Costs around € 8-15.

SMD Stepped Attenuator
or
AL-SMD-Pot

@funhouse61
I tested these parts against the € 150, - - 250, - 48 Step SMD potentiometers and couldn't hear any difference.
And relay-based volume controls are available from € 30 with 128 - 256 Steps.
 
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Joined 2011
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The Forum software won't let you link-quote to a post in a thread that's been closed, so I'll separately provide the (link) and then the

I am glad that I tried out the eBay DACT attenuator module [in the T2/Noir headphone amplifier], and in listening tests it seems not to change the sonic presentation at all. I.e. same as the ALPS RK27.

However, I discovered that I like the ALPS more, for other reasons. The DACT has "only" 21 steps, which is too few for my taste. I prefer the continuous adjustment on the ALPS. Worse, the DACT has less friction; it's far easier to turn the volume knob than on the ALPS. I prefer the stiffness / solidity of the ALPS.

For me: good experiment, worthwhile results, non ambiguous conclusion.

edit- whoops, forgot to say, mine is 20Kohms. I bought from the seller who offers them two to a package.
 
I won't be putting my Alps back, as I like the 21 steps better :) also, the stepped attenuator measures quite a bit better with regards to channel matching. I never measured.the alps before, but seeing how perfect the attenuator measured, I was curious. The Alps is never perfect, and the level of matching differs depending on volume position. It is actually worse in the middle position compared to the extremes, contrary to what is often said.

I would probably hard pressed to pick one over the other in a blind test just listening, but I like the attenuator better for the same reasons you prefer the Alps. Funny how that works :)
 
So, I just finished my WHAMMY build a few days ago. This is my first dedicated headphone amplifier so i don't have much comparison. But it does blow my Astell & Kern SE100 (portable DAP) out of the water. Right now i am using the Burson Audio Vivid discrete opamp. I have the classic on order and have a few other opamps that i am looking at acquiring. This has been a fun little project.