What?! Another headphone amp kit?! Smack me!

Doc B. · 36629

0 Members and 1 Guest are viewing this topic.

Offline Jim R.

  • Hero Member
  • *****
    • Posts: 2194
  • Blind Bottlehead
Reply #75 on: February 03, 2012, 02:54:12 PM
Yes, mine is still in the box and probably will be for a while yet. Got to get at least one s.e.x. amp and/or stereomour working first and then the Eros.

I'm definitely looking forward to what others say as more people get them built and broken in.

-- Jim

Jim Rebman -- recovering audiophile

Equitech balanced power; uRendu, USB processor -> Musette DAC -> 5670 tube buffer -> Finale Audio F138 FFX -> Cain and Cain Abbys near-field).

s.e.x. 2.1 under construction.  Want list: Stereomour II

All ICs homemade (speaker and power next)


Offline M^Cubed

  • Newbie
  • *
    • Posts: 9
Reply #76 on: February 02, 2023, 07:05:36 AM
@Doc B. - where can I go to find a build manual for the SMACK WOT.  Also, have there been any design adjustments for 'improvements' ?   I have some M-caps I believe upgraded in there and a TKD pot.

Thank you.

We just did the test firing of a new headphone amp prototype that I plan to take to the Bay Area Head Fi meet this weekend. The amp is designed as a complement to the Crack OTL headphone amp for high impedance headphones. This new design is a WOT (With Output Transformer) design that has been developed for low impedance headphones. I decided to call it Smack. It uses two 5687 tubes. One half of each 5687 is an active loaded single gain stage that is parafeed coupled to an output transformer. The prototype has a single tap of 32 ohms, however we might alter the production transformer design so that it could be configured for 32, 64 and 128 ohms. The second half of each 5687 is used in an active loaded hybrid shunt regulator. The prototype has been built on a S.E.X. amp chassis and uses the same PT-3 power transformer used in Crack, S.E.X. and Foreplay III. The gain stage and shunt reg use the new Soft Start PC board that we use in the new Paramount.

Unfortunately I only have some inexpensive Sennheiser 201s here today to try the amp with. But even with those it's showing promise. It's dead quiet, seems pretty quick and there seems to be pretty good bass for an amp that's about 2 minutes old. Gonna burn it in a bit and we'll see what folks think at the meet. Before anyone asks, I don't have a firm price. But it would probably hit somewhere in the $350-$400 range.



Offline Doc B.

  • Administrator
  • Hero Member
  • *****
    • Posts: 9593
    • Bottlehead
Reply #77 on: February 02, 2023, 07:46:06 AM

Dan "Doc B." Schmalle
President For Life
Bottlehead Corp.


Offline M^Cubed

  • Newbie
  • *
    • Posts: 9
Reply #78 on: February 02, 2023, 01:52:23 PM
Thank you very much!