Dynahi?

[diebenkorn]

Is it still possible to get a Dynahi built and if so how much would it cost? Or would it be wiser to just get a headroom desktop with max modules?

[JBLoudG20]

Is it still possible to get a Dynahi built and if so how much would it cost? Or would it be wiser to just get a headroom desktop with max modules?

It's all about the Beta Deuce Deuce, now.

[n_maher]

I haven't seen a set of Dynahi boards for sale for a good long time and posty's amp was the one of the few that I've seen listed that I would have felt ok telling someone to buy.

[xand1x]

It's all about the Beta Deuce Deuce, now.

You mean Beta Deuce Quad

[Pars]

Dan Gardner still has boards available (as do some of us ). The input dual FETs (2SJ109 / 2SK389) are no longer available, but can be replaced with singles (2SJ74 / 2SK170), which have also been discontinued.

IIRC, the only commercial builder that I might have trusted was sft, and I'm not sure if he is still building them. And as mentioned, more interest in the B22 these days.

[JBLoudG20]

You mean Beta Deuce Quad

Heh, the BDQ is not up to my Kef standard.

[luvdunhill]

Dan Gardner still has boards available (as do some of us ). The input dual FETs (2SJ109 / 2SK389) are no longer available, but can be replaced with singles (2SJ74 / 2SK170), which have also been discontinued.

IIRC, the only commercial builder that I might have trusted was sft, and I'm not sure if he is still building them. And as mentioned, more interest in the B22 these days.

B&D has 8 2sk389 in stock right now, I'd buy them if I were you.

[jp11801]

as a somewhat contrary view I always like the dynahi over the beta amps. Although the dynahi doubles as a portable space heater it continues to be my favorite solid state amp. The beta is a great amp something in the presentation leaves me slightly detached from the music while with the dynahi I am immersed in the music.

The builds on the betas were better though my Veda was of suspect build quality mostly attention to detail but sounded great.

[Pars]

B&D has 8 2sk389 in stock right now, I'd buy them if I were you.

I still have a few (of each)...

Since I have the heatsinks from the GB, etc., I should probably get around to building one one of these days

The only Dynahis I ever saw in person were KG's and Dan Gardner's Dynamight. Of the commercial pics, sft's probably looked the best, the Veda's looked OK, and trevornetwork's.... well, lets just leave it at that

[postjack]

The builds on the betas were better though my Veda was of suspect build quality mostly attention to detail but sounded great.

Same here with my Veda. Sketchy attention to detail, but still the best sounding amp I've personally owned.

[JBLoudG20]

still the best sounding amp I've personally owned.

So the natural route is to sell it.

[diebenkorn]

Thanks for the replies. Beta is out of reach right now :'( any other suggestions no love for the headroom,CK? budget around 1000$) Pars if you do get around to it would you be interested in building me one?

[Pars]

Were yours (jp11801 and postjack) Dynahi's or balanced (dynamight)?

Dammit, wasn't looking for a headphone project, but since I already have most of the stuff....

[JBLoudG20]

Were your's (jb and postjack) Dynahi's or balanced (dynamight)?

Dammit, wasn't looking for a headphone project, but since I already have most of the stuff....

Mine? Headphones suck.

[n_maher]

Thanks for the replies. Beta is out of reach right now :'( any other suggestions no love for the headroom,CK? budget around 1000$) Pars if you do get around to it would you be interested in building me one?

I'd go w/ the balanced desktop w/ Home modules before I went single-ended MAX.

[justin]

IIRC, the only commercial builder that I might have trusted was sft, and I'm not sure if he is still building them. And as mentioned, more interest in the B22 these days.

I think this is partly because the free-for-all dynahi building once boards were available drove the price down to practically nothing, killing the value of the design, and with it the opportunity to offer properly built units at realistic prices

[postjack]

So the natural route is to sell it.

To change my statement, the Wheatfield sounds better with the HD650, and I am confident the balanced beta22 will sound better with everything.

[JBLoudG20]

To change my statement, the Wheatfield sounds better with the HD650, and I am confident the balanced beta22 will sound better with everything.

Now buy a bike!

[luvdunhill]

I think this is partly because the free-for-all dynahi building once boards were available drove the price down to practically nothing, killing the value of the design, and with it the opportunity to offer properly built units at realistic prices

just curious, are there any significant changes / improvements to the design? I have a set of boards and all the required parts, including transformer. I was sorta thinking about it as a preamp, but I would like to know its max voltage output, as I would use it into a Pass F4 current buffer and need lots of voltage swing.

[n_maher]

http://www.ibiblio.org/tkan/audio/dynahi.html

I think that the only notable improvement has been folks using a sigma22 for the power supply. And it would be a pretty absurd preamp.

[jp11801]

my dynahi was single ended with only one of the rcas wired up , they are probably the best used amp value out there

[Pars]

just curious, are there any significant changes / improvements to the design? I have a set of boards and all the required parts, including transformer. I was sorta thinking about it as a preamp, but I would like to know its max voltage output, as I would use it into a Pass F4 current buffer and need lots of voltage swing.

I'm not sure how this would work as a preamp... seems somewhat massive overkill from a power perspective.

Have you ever looked at something like the Pass Aleph P1.7 on diyaudio? The boards aren't available anymore, but the layout was pretty easy on them...

As Nate mentioned, I would be really tempted on the Dynahi to use the sigma22 PSU(s) instead of the original, as blowing up $20 OPA541s isn't real enticing to me, even though I have the boards.

[luvdunhill]

well, since my amp would provide no voltage gain, absurdity is merited. Aleph doesn't have enough voltage gain (I'll go hunt for what I need)

edit:

according to Papa: "...which is about 16-20 dB (gain) and +/-20V (swing) per input leg"

the amp can handle a +/-40V unclipped output in balanced mono (as it's called in the docs)

[justin]

just curious, are there any significant changes / improvements to the design? I have a set of boards and all the required parts, including transformer. I was sorta thinking about it as a preamp, but I would like to know its max voltage output, as I would use it into a Pass F4 current buffer and need lots of voltage swing.

there's no reason to use it as a pre-amp. it's the same design as the dynalo, but with higher power output transistors, and cascoded input stage which is required due to the 60V of power supply. just more noise and a slightly more complex design.

[luvdunhill]

well, since my amp would provide no voltage gain, absurdity is merited. Aleph doesn't have enough voltage gain (I'll go hunt for what I need)

edit:

according to Papa: "...which is about 16-20 dB (gain) and +/-20V (swing) per input leg"

the amp can handle a +/-40V unclipped output in balanced mono (as it's called in the docs)

heh. I think the replies to this thread got lost at some point. Anyways, I'm still looking for a preamp project that can handle the above. I think the preamp I posted here:

http://www.head-case.org/forums/speakers/2471-preamps-3.html#post73554

is probably the most accessible project out there. I agree with Kevin's comments but don't really know of a good project off hand that will address his design concerns and get me the specs I need.

So, last call for projects!