jamiecantar
Well-Known Member
i bought a Dynaco st-70 for parts that came with no transformers. Are the transformers proprietary or can i use another transformers from other amplifiers or new aftermaket ones out there?
Dynaco ST-70 for parts transformer replacement options
- Thread starter jamiecantar
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There is several sources for Dynaco transformers ( clones of course but exacr replicas)
Visit dynakitparts.com or tubes4hifi.com for new transformers.
Triode Electronics also has Dyna transformer clones albeit a bit pricey. Theirs appear to be in stock whereas it appears that Dynakitparts are currently out of stock. Tubes4hifi appear to have the best (cheaper) prices for their Dyna clone transformers. No affiliation with any of these guys although I have bought parts from Triode and Dynakitparts in the past.
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Yes and no. If you want it to work exactly like a Dynaco, you want modern reproduction Dyna iron. The output transformers in particular really ought to be originals or the modern copies of the originals if you don't want to get into re-working the feedback and all to make sure its proper and stable. They aren't the cheapest thing on the planet but the originals are extremely good and by all reports the modern ones are a faithful copy.
the power transformer is also available and the modern ones are supposed to be beefier. If I'm being honest though, there isn't anything real special about the power transformer. Any that will supply appropriate voltage and current will work, but that gets into questions about whether or not it fits the holes, and if you are going to have issues with core alignment. If I had a usable transformer in my parts stash I'd stick one on. If i was buying one, I'd just buy what is designed to fit there.
the power transformer is also available and the modern ones are supposed to be beefier. If I'm being honest though, there isn't anything real special about the power transformer. Any that will supply appropriate voltage and current will work, but that gets into questions about whether or not it fits the holes, and if you are going to have issues with core alignment. If I had a usable transformer in my parts stash I'd stick one on. If i was buying one, I'd just buy what is designed to fit there.
+1 I think you will find the price great and the product very good. I have used his output transformers to great effect.
As far as the power transformer, there are more options that fit if you can do without the rectifier tube and go solid state rectification.
jamiecantar
Well-Known Member
All great suggestions, thanks guys. thats what i thought, you have to use one that is exact in specifications to the originals...
There is a set of originals on eBay right now out of Canada for for a little over $400 USD. Also, complete and total long shot and I very much doubt this is the norm, but when I was building my MK3 clones I was after a set of power transformers. I really wanted modern 120VAC versions, but everyone was out of stock except Triode and they are a bit over the too-pricey threshold IMHO. Dynakitparts had a mix-matched vantage used pair listed so I contacted him for a price. He told me he had some new stock just in and if I checked back in a few minuets he'd have two listed in stock. He did, I bought them... Again, no idea if this is the case for other items he has listed out of stock, but it may not hurt to contact him and ask. At least ask when he expects new stock in. He picked up the phone and was very helpful.
