opiniion survey on amplifier style

I've been making these custom amps for a few years now, but I'd like to standardize on the design.
These layouts are shown using standard Dynaco/VTA transformers, rather than the round toroids.
(the amps can be built either way, same price, same quality).
The photo below makes the layout of the upper design with the output tubes staggered
The 2nd layout at the bottom puts the tubes across in a straight line.
Let me know your preference.
BTW, with a steel chassis for the base, this only raises the price of an ST70 or ST120 amp by $50.
With the wood chassis for the base, the price is $150 above the usual price.
The photo at the very bottom was a custom ST120 I did about ten years ago.

I much prefer the "staggered tube" config. Tubes better spaced, so cooler design. Also a cooler design

Blitzen wrote:I much prefer the "staggered tube" config. Tubes better spaced, so cooler design. Also a cooler design :)

I agree. I also like not seeing the caps if it doesn't create a rat's nest under the hood.

Staggered, no caps = cleaner look

I like them both. I prefer the 2nd pic but would not want the caps sticking up through the plate.

The partially hidden, or exposed - glass half empty or half full? - caps look(s) really silly. Mount them on top.

I like the first pic. Staggered tubes, no caps showing, wood base. Very clean and classy looking.

Never understood why Dynaco amps had/have exposed driver boards. What's the appeal in seeing exposed caps, resistors, transistors, tube sockets, etc.? I wonder why David Hafler did it to begin with?

wgallupe wrote:I like the first pic. Staggered tubes, no caps showing, wood base. Very clean and classy looking.

Never understood why Dynaco amps had/have exposed driver boards. What's the appeal in seeing exposed caps, resistors, transistors, tube sockets, etc.? I wonder why David Hafler did it to begin with?

Dynaco never exposed driver boards, they had a cover over the amp.

And to add to PeterH comment. Use the covers. Once you need to work on them the board mounted on the chassis top makes these amps the easiest, most accessible of all the vintage gear. Work on the other vintage top manufactures products for a while and it is a pleasure to come back to a Dynaco. Simple and straightforward.

They were not intended to be used without the cover and some of those exposed voltages make it a risk to do so. I suggest you buy those new chassis if you want good looks with minimal risk.

I like the first picture with the tubes staggered.

I like the first pic, but I don't care for the driver tube sockets sticking as they do when the output tube sockets are 'flush' with the deck. Not a 'deal-breaker'.....and I understand that you probably have them PC mounted unter the deck. BUT..... I just don't like the inconsistancy! I believe there are not people who are PC mounting output tube sockets on a board that screws to the bottom just like the driver board. So, if you were to adopt this technique as part of your design, 'yes!', you'd have two more PC boards to have to supply (one for each side). BUT..... with the quality of of today's boards, you'd make the kits themselves somewhat easier to construct, probably more reiiably built too since the wiring aspect of the output tube area would be controlled by the PC board..... AND, the tube sockets could all be equally protruding above the chassis deck. I know it's a petty comment, but seems like going through all the trouble to 'sub' mount the driver board (as opposed to 'open' mount it like in the OE Dynaco design), cut holes for tubes and sockets to make it all look 'neet', then to do the output sockets 'the old fashioned' way.....that just seems self-contradictory. Anyway, I much prefer the staggard look of the #1 pic!!

So, while I'm at it, I have to ask: Are there standard type OTs under the round covers that are just mounted below the deck and then also protruding up through and just finished off with that round cover? And finally, is the PT a torroid also mounted under the deck?

Thanks! Tom

Tom,
the first top photo uses all toroids, both outputs and power.

Either style is OK with me, BUT move the input jacks AWAY from the output transformer and power transformer. Can you give details on the toroids used in the output?

Yea, I'd like some detail on the torroid OTs as well. I wasn't aware there was such a thing.......

send me a PM or email if interested in an amp with the toroidal output transformers.
They are super high quality and actually cost less than conventional EL transformers.