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I'd like to build a pair of MkIII's from scratch on my own chassis.

I just need a few pointers and suggestions. I've built 2 point to point amps so far that weren't all that complicated so I'm fairly confident I can do it.

Should I build the psu or buy the SDS board?

Is the SDS board the whole psu minus the 5AR4?

I know I need the Poseidon board

The Poseidon manual has a parts list that looks like it includes the rest of the parts that would complete an amp. Is that right?

Using Poseidon or other driver boards will save you time on construction, even though you sound confident enough to handwire one. What irons are you going to use? Hammonds, Dynaclones, Edcors, or others?

The SDS cap boards are great for solving MKIII PSU's problem with their inadequate can caps. You can choose to use either diodes or 5AR4 for rectification with the boards. Either method of rectification will be fine as the cap boards can handle upto 630 VDC. Unless you're planning on building a pair of MKIIs, you will need a choke in the PSU. So, the board alone won't cut it.

I like MKIIIs, except I never fancied their chassis size. Make sure that you give yourself a plenty of room in your chassis. I would totally go for chunkier chokes to mount on top.

It shouldn't be a problem to build your own MkIII "from scratch" on your own chassis, especially if you plan to use the Poseidon boards. Technically, you could wire it ALL point to point and skip the Poseidons. Personally, I like the boards.

You'll need:
Chassis
Tubes
Transformers and chokes
Poseidons and parts
Tube sockets (8 and 9 pin)
Power supply components (or SDS cap board)
Bias supply components
Miscellaneous parts (input jack, binding posts, power switch, power cord, etc.)

I think it's all outlined in the Poseidon manual, more or less. Grab a copy of the original Dynaco MkIII assembly manual as well.

http://www.dynakitparts.com/store/manuals/

SDS-PAGE wrote:What irons are you going to use? Hammonds, Dynaclones, Edcors, or others?

I'd like to use hammond or dynaclone for the power. But for the output I'm torn between having electra-print wind a pair or trying the dynaclone. I would assume edcor's are the cheapest.

What combo is yielding the best bang for the buck?

Ty_Bower wrote:Personally, I like the boards.

I'd pay good money for everything on one board

I think the Eiclones with the CCS option would be the closest thing to that. But, I don't think Shannon has any Eiclones available right now.

sbelyo wrote:

SDS-PAGE wrote:What irons are you going to use? Hammonds, Dynaclones, Edcors, or others?

I'd like to use hammond or dynaclone for the power. But for the output I'm torn between having electra-print wind a pair or trying the dynaclone. I would assume edcor's are the cheapest.

What combo is yielding the best bang for the buck?

You may want to look into toroid output and power transformers.

http://audio.engineeringvista.com/Trafo ... /index.htm

You can get a quote, here -
http://audio.engineeringvista.com/Trafo ... r_form.htm

There are some current production EI transformers from China. You can find them on ebay, but buyer beware.

I'd like to use hammond or dynaclone for the power. But for the output I'm torn between having electra-print wind a pair or trying the dynaclone. I would assume edcor's are the cheapest.

What combo is yielding the best bang for the buck?

If it's economy that you're after, you can't go wrong with Edcor OPTs. They are good performers for the price. If you can afford it, I'd go with Electra-prints. Pricey, but worth it.

Dynaclone and Hammonds are good options too. No need to hunt for original Dynaco OPTs. They both perform just as well.

If you really feel like spurgin', look for a pair of Peerless OPTs on eBay. You need to hear them sing to truly appreciate. Yellow_Light_Colorz_PDT_11

P.S. Incidently, there are some Peerless OPTs for sale on eBay:

http://cgi.ebay.com/PAIR-ALTEC-KT88-OPT-TRANSFORMER-MORE-FOR-TUBE-AMP_W0QQitemZ350047823912QQihZ022QQcategoryZ67815QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

Troidal output transformers are a waste of time and money IMO. Magnequest is a good bet, Edcor's larger units seem to perform well, and the Dynaclone iron is also pretty solid. Electraprint and O-netics are nice, but you may end up waiting a fair bit of time for them. I would generally stay away from Chinese output iron if you can, although there are some decent transformers rolling out of Taiwan.
-Paul