Our new preamp kit - Smash

Doc B. · 11618

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Offline Paul Birkeland

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Reply #15 on: April 21, 2014, 12:36:02 PM

Wish I could justify getting onee, but not at least until the backlog is taken care of.



Yeah, you sure have a lot of projects going!

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline xcortes

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Reply #16 on: April 21, 2014, 01:07:18 PM
Paul,

How complicated is the build? Again, the quickie being one and the BP 10 I would assume a five.

Xavier Cortes


Offline Jim R.

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Reply #17 on: April 21, 2014, 03:26:07 PM
PB,

Yes, but now I have a lot more energy and overall better health plus a nice electronics work area and a decent wood shop, so other than idintifying terminals and dealing with circuit boards, no real roadblocks. Oh, and with the analysis paralysis out of the way and a real plan in hand, the work feels fun and nicely mapped out for me.

-- 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 Karl5150

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Reply #18 on: April 23, 2014, 04:25:34 AM
Crackphones and Smash in a couple of months. It doesn't sound like anybody at BH headquarters is coasting.
I want 'em both!

Karl
Downstairs: Planar3>PH-16>Stereomour II>OB Betsy+
Upstairs: RP1>Eros/CD5004>Seductor (2x Monoblocks)>FH3
Office: Modi Uber 2/Sirius>SEX2.1.1>µFonken FF85WK + DC160 subs
BR: FiiO M6>SEX3.0.1>ScanSpeak 10F + TangBand W6 (Mono)/DT770Pro
Garage: X12 streamer>Quicksand>Minimus 77


Offline Mr. Davis

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Reply #19 on: April 25, 2014, 12:05:54 PM
Doc,

Can you give us some hints of what this new (middle price range) power amp will be?

Perry Davis


Online Doc B.

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Reply #20 on: April 25, 2014, 12:11:48 PM
It will be EL84 based, about 4.5 watts per channel. As usual we are doing things a little differently than others. I will give some more info once we are a little farther along with the project.

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


Offline Paul Birkeland

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Reply #21 on: April 25, 2014, 01:44:19 PM
I thought I'd also mention another feature in this thread that didn't make it into the announcement.

With the particular regulator that we are using, I am able to limit the maximum available current that the regulator will output.  For a directly heated tube, the filaments draw considerable more current when cold than when warmed up.  This puts a reasonable amount of stress on the filaments, so by limiting the current draw at start up, we can extend tube life a bit.

It is worth mentioning that this is a phenomenon that tube manufacturers are aware of and design for, so it is not mandatory and we do not plan to retrofit it into other kits. 

-PB

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline dougmon

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Reply #22 on: April 29, 2014, 11:31:08 AM
I hope I didn't miss something in reading about this, but the specs say one of the outputs can be used for a dedicated headphone amp. Does this mean one of the outputs can be wired as a fixed volume line out?  Will there be instructions to do this?

Thanks!



Offline Paul Birkeland

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Reply #23 on: April 29, 2014, 11:49:40 AM
You could wire a Tape Out to one of the outputs for this purpose, but I would instead recommend using the Smash as a buffer to drive your headphone amp instead.

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline Cleet Torres

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Reply #24 on: May 05, 2014, 04:43:25 AM
It will be EL84 based, about 4.5 watts per channel. As usual we are doing things a little differently than others. I will give some more info once we are a little farther along with the project.

Doc, am I assuming correrctly that the price range of the new amp will be below the Stereomour?

I cannot quite swing the $$ for Paramounts but I was toying of building Stereomour poweramp - sans selector, volume etc to run off my foreplay III (and soon my Smash).

How will the new amp compare with the stereomour? When I read "EL84", which is a nice sounding pentode for sure, I'm thinking it's not going to be able to compte with a 2A3  stereomour no?

Thanks
Cleet.



Online Doc B.

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Reply #25 on: May 05, 2014, 05:19:33 AM
Yes, the EL 84 amp is intended to cost less than the Stereomour and give the same or a little more power. We are still working up the design at this point and thus it's premature to make some definitive statement about how it sounds.

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


Offline Sonido

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Reply #26 on: July 05, 2014, 01:03:33 PM
Out of curiosity, does rolling the center VR tube do much in terms of affecting the sound?



Online Doc B.

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Reply #27 on: July 05, 2014, 02:25:31 PM
Rolling the bypass cap on it probably has more impact.

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


Offline Mr. Davis

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Reply #28 on: July 06, 2014, 06:17:57 AM
Rolling the bypass cap on it probably has more impact.

Are you talking about the  .1 uf 400V film capacitor? I was wondering about that.

Perry Davis


Offline Grainger49

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Reply #29 on: July 06, 2014, 06:33:36 AM
If Smash follows the FP III regulator circuit a USSR Military surplus 0.1uF@600V bypass will sound better there.