"WHAMMY" Pass DIY headphone amp guide

My BOM is just about sorted.

I'm having some trouble sourcing a transformer though, all the recommended options are not available/on back order at mouser and digi-key.

Has anyone tried the recommended alternative?

Here's a link to a factory surplus transformer that fit the PCB will work beautifully - You will want to make R16, R22, R29, R32 15ohm if using this transformer.

70054K PC Mount Transformer 110/230V-18/36V 110V-36V 110V-18V 230V-18V 230V-36V

I'm assuming the resistor change is to take into account the lower voltage secondaries?

Will the lower 15VA rating be an issure?

(sorry I'm a bit of an electronics newbie)

Cheers,
Jeremy
 
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My BOM is just about sorted.

I'm having some trouble sourcing a transformer though, all the recommended options are not available/on back order at mouser and digi-key.

Has anyone tried the recommended alternative?



I'm assuming the resistor change is to take into account the lower voltage secondaries?

Will the lower 15VA rating be an issure?

(sorry I'm a bit of an electronics newbie)

Cheers,
Jeremy

Yes, I used the transformer from surplussales.com. It worked fine for me.
 
Burson Vivid v Classic

I am forever changing my system around to try new things, the Whammy being relatively new.

Overall, using the Whammy as a pre, the system now has too much gain, so I swapped out my power amp for a power buffer, similar to a crippled F4, it's as neutral as I can make it. I spent a week acclimatising to it before pulling the Muses 03's and trying the Burson's, I gave each one a 1 week audition.

First in was the Vivid.
I immediately noticed was how 'up front' it is, a little too much in your face, the next immediate thing I noticed was the dynamics, this thing is on steroids! the dynamics are great. A bit more listening revealed on some poor recordings the top end can get a bit hard and scratchy, which could get a bit tiring at higher listening levels. There is some loss of finer detail throughout the spectrum, very low bass appeared to be slightly attenuated, this is probably due to the overall tonal balance.
The sound stage is wide with good height and is forward of the speakers, It has good instrument separation.

Swapping from the Vivid to the Classic.
It came as a bit of relief, the overall balance was more relaxing and has a warmer tone. The Classic is superior in almost every way, except the dynamics which are much softer, maybe a little too smooth which leaves you wanting a bit more bite. Long term listening was never fatiguing but could sometimes get a little boring due to the softer dynamics.
If the speed and dynamics of the Vivid could be injected into the Classic, you would have something near unbeatable.

Swapping back to the Muses 03.
I missed the nice warm 'tone' of the Classic, the Classic also has better fine detail, but overall; I prefer the Muses 03, it seems to be better balanced in my system, more foot tapping, YMMV.

Overall conclusion, lay back or dull systems would benefit with the Vivid, over forward or bright systems, choose the Classic.

I'm waiting for the delivery of a Staccato OSH-DHa to see how that fairs.
 
I’ve tried to do a semi-rough difference in cost calculation based on what I could figure out as the kit parts that I swapped out for “premium” versions.

1) Glassware Audio’s “House GND” ground isolation board/kit: House GND Kit - $9.95 (1)

2) SparkOS discrete, low-noise regulators: Sparkos Labs, Inc. audio power supply discrete voltage regulators (one SS7815 and one SS7915) - 47.00 each (note I bought these at %15 off as he had a sale going). The stock ones are https://www.mouser.com/ProductDetai...=/ha2pyFaduj3LqfbGA7x66QboUvVoNfvQqJMkUKO/T8= and about $.57/each (you need a 7815 and a 7915). Difference here is $47*2-1 ~= $102.95.

3) Burson Classic 6 OpAmp (Burson Audio V6 Discrete Opamp – diyAudio Store) $70 each.
Texas Instruments RC4580 op amp (https://www.mouser.com/ProductDetail/Texas-Instruments/RC4580IP?qs=sSOk4GDDv7yJoSozpf3%2Brw==) $.58.
$70-.$.58 ~= $69.

3) UXCEL M4 rubber isolators for the main board for some vibration isolation: uxcell M4 Male Female Rubber Mounts, Vibration Isolators, Shock Absorber 10mm x 10mm Black 8pcs: Amazon.com: Industrial & Scientific -$12.39 for a pack of 8, 1 package needed. Standard stand-offs are about $.50/each * 6 needed for the project which is about $3.

4) I used 2 rubber washers under the transformer to help dampen mechanical vibrations there. I bought these at HD. Everbilt Neoprene Washer (https://www.homedepot.com/p/Everbilt-1-2-in-x-2-in-Black-Neoprene-Washer-815878/204276446) $1.23 * 2 (I used two).

5) Solen 1 uF 700V Silver Sound MKP Film Caps for the input coupling caps (C1/C2). (Solen 1.0uF 700V Silver Sound MKP Silver Metallized Polypropylene Film Crossover Capacitor) $15/each * 2. Stock caps look like these (https://www.mouser.com/ProductDetail/Panasonic/ECW-FE2W105JA?qs=FCwj0qo8zF%2Bmbv2kO1EgCw==) which are about $.43/each * 2.

$30 - $2 ~= $28.

6) GlassWare Select-5 5-input switch/breakout board: Select-5 Signal Selector Switch (https://glass-ware.stores.yahoo.net/select5.html) $15.

7) blue front panel knobs from TESI Switch: Amazon.com: Tesi Solid Aluminum Replacement Knob Set for Line 6 Helix Floor and Rack (Hot Pink): Musical Instruments. $44. I don’t know where the stock knob is gotten from but I’ve seen similar ones on AMZN in the $5 department. Note you need two: one for volume, and one for the selector.

8) blue front LED uses a power supply breakout board from Gareth (Gaz213) that he helped me locate off the main supply. Board was about $5 each. LEDs all basically cost the same so no savings for a blue one.

9) DiyAudioStore Alps potentiometer breakout board (https://diyaudiostore.com/collections/misc-pcbs/products/rk27-breakout-pcb) These are $5/each and well worth it!

10) Neutric D-style RCA i/o connectors (https://www.mouser.com/ProductDetai...bJzGI4/4l%2B6KFs6UysXwkcqbNL5yPvZazi2bt7bvA==) $4.45 each. I used 6. The stock RCA connectors are similar to these (https://www.mouser.com/ProductDetai...EpiMZZMvlX3nhDDO4ANv5m%2BWbGXRyC%2BK9eLKHxrE=) which are $1.72 each.

($4.45 - $1.72 ) * 6 -> $2.73 * 6 ~= $16.38.

11) Nichicon Audio KA(M) and KG(M) caps for the power supply (50V filter caps in the supply) and elsewhere. For the 22uFs I used the Muse types (bright green).

Nichicon Muse 22uF 25V caps (Mouser https://www.mouser.com/Search/Refine?Keyword=ues1e220mem ) 6 * $.47. The stock caps are Elna Simlic II’s which are about $.30/each (https://www.mouser.com/ProductDetail/Elna/RFS-25V220ME35?qs=HV/SjD3ivR/i1/x/n517CQ==)

Roughly an additional $3.

Nichicon 220uF 50V UKAs (https://www.mouser.com/ProductDetai...By/QjvSYUSQw7FpY4sfr5M3jpd0WA2PRAGT3gt9oQqZYh) are about $.78/each. The stock ones appear to be Kemet (https://www.mouser.com/ProductDetai...GAEpiMZZMukHu%2BjC5l7Yb6Zt8jw0u8hF7hWMHHNZIY=) which are about $.50/each. There are 6 of these so we get about $.25 * 6 = $1.50.

Nichicon 3300uF 50V (power supply filter caps) (https://www.mouser.com/ProductDetai...QSeJD/%2By37V3W/9CFiNzaZM3IwE4Xd8NxmwG6PceA==) which are about $2.87 each (you need 6). The stock are FC Series Panasonics (https://www.mouser.com/ProductDetai...05zz2/Ww%2BaoTveFxTVmBxbre7eKLdBxxO2NKs/3/sQ=) and those are $1.78/each. Here we add about a dollar, so multiply by 6 and we get $6.

13) WIMA MKS 2 bypass caps everywhere except in the power supply. The ones that come with the kit appear to be these (https://www.mouser.com/ProductDetai...X1Z5YPvFSK3K1y9%2Bcpu20pGq38%2BlcyTTYxElbWA==) which are $1.98/each. The Wimas found here (https://www.mouser.com/ProductDetai...cNBgjYauIqbFtu5%2B2CdSw%2BcGgUxAqoh2KPNFUlA==) are about $.30/each. There are 4

The bypass caps (2 optional in the build so lets actually call it 2), so here we actually save about $1.68 * 2 !


This is the rough sum of the additional costs to what I built from the kit version:

$102.95 + $69 + 3 + $2.50 + $28 + $15 + $44 + $5 + $16.38 + 3 + $1.50 + $6 - $3.36 = $299.69. The diyaudio kit costs $189 excluding the chassis which from where I sit, using it as-is is a freakin awesome deal even using the stock TI OpAmp. Beyond that its largely changing the sonic character of the preamp much in a way that is subjective. For me adding one of the discrete OpAmps for about $70 and $100 for the discrete regs gets you into top-shelf hi-fi audio land.

With that in mind, we should thank Jim/6L6 and the diyaudiostore folks for putting together such an awesome kit from Wayne’s initial design/build at such a reasonable price every time we listen to this thing.

Now back to listening to some really amazing music with my Whammy 2!

—Tom

Definitely worth a try then :)


A BIG advantage for me personally with the Whammy is the fact that its quite simple to roll opamps on this platform and figure out what you really enjoy versus taking others' word for it (including manufacturers). Go ahead and order up the different discretes and try each one. I've found that all of them are quite clearer/sharper/easier on my ears and provide much more realistic imaging and realistic vocals in particular, and better defined (low low) bass as compared to the monolithics. Try them all and see for yourself. :)
 
Using AC relay for front panel LED

I recently built a one of the AMB.org signa 22 power supplies for another project, and noticed that on the DAC project

The γ3 high resolution DAC where they show this AC relay as the means to enable the front panel LED (plus a diode or two and a resistor ahead of the LED):

https://www.mouser.com/ProductDetai...sj69HIp9HY79stR3c4hn6J5K0unEGRgfjjlgBkF4ZGQ==

Has anyone else tried this? I ask because I went to considerable lengths with the front panel LED on my last Whammy build and this seems a lot simpler.

--Tom
 
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@thomasnadeau: It would be best to get clarification from the AMB gurus. It appears to me (NOT an AMB guru!) that digital signal "SSRTRIG" controls two things: (1) it lights or extinguishes the LED ; (2) it controls a solid state relay which connects, or disconnects, the AC mains to transformer T1 primary. Transformer T3 primary is not switched by the solid state relay.
 
@thomasnadeau: It would be best to get clarification from the AMB gurus. It appears to me (NOT an AMB guru!) that digital signal "SSRTRIG" controls two things: (1) it lights or extinguishes the LED ; (2) it controls a solid state relay which connects, or disconnects, the AC mains to transformer T1 primary. Transformer T3 primary is not switched by the solid state relay.

Good point. Its hard to see from the figures and instructions, exactly how to hook it up which is why I asked here, but I'll try over there too.

Thanks!

--Tom