I'm planning an amplifier build in my head and I do not have the power transformers yet. I've always used EI transformers but for this project I'd like to try using a torroid transformer. First off, I'd like to know the names of some manufacturers so that i can search their catalogs.
Hammond doesn't have much in the range I'm looking for. What are my other options? Audiophile cachet is of little importance to me I'm looking for a standard commercial product which I can buy for a reasonable cost and build 4x 6550 monoblock amplifiers using potted Dynaco 430 transformers via a solid state voltage doubler.
Secondly.
Has anyone got any opinions or experiences to share as to the pros and cons of one vs the other?
EI vs Toroid?
Hammond doesn't have much in the range I'm looking for. What are my other options? Audiophile cachet is of little importance to me I'm looking for a standard commercial product which I can buy for a reasonable cost and build 4x 6550 monoblock amplifiers using potted Dynaco 430 transformers via a solid state voltage doubler.
Secondly.
Has anyone got any opinions or experiences to share as to the pros and cons of one vs the other?
EI vs Toroid?
I don't have any EI vs. torroid opinions, but Antek is one that is used for electrostratic headphone amps, both tube and SS, for stuff like the Gilmore Blue Hawaii, KGSHV, Carbon, etc.
https://www.antekinc.com/
https://www.antekinc.com/
I've also used Antek for a few builds. For off-the-shelf toroids, they are a good option.
The other company that I have used a lot for custom toroidal power transformers is Toroidy in Poland. Their Supreme Audio Grade transformers are very well built and look great with their polished stainless case. It generally takes a few weeks from order to delivery in the US, and the prices are a fair amount higher, but the quality is exceptional.
https://sklep.toroidy.pl/
The other company that I have used a lot for custom toroidal power transformers is Toroidy in Poland. Their Supreme Audio Grade transformers are very well built and look great with their polished stainless case. It generally takes a few weeks from order to delivery in the US, and the prices are a fair amount higher, but the quality is exceptional.
https://sklep.toroidy.pl/
The de minimis exemption in the US doesn't expire until May 1, so if you might be able to get it delivered before then if you ordered soon. The last pair of custom transformers I ordered took 19 days from order to delivery in Oregon, with no import duties. This was in February.
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Toroid power transformers work well under one condition; no DC on your mains. Most of the reported problems people have with toroidal power transformers has more to do with the quality of the mains feed than it does with the transformer itself.
So do yourself a favor. Before you go any father, measure your mains and make sure you don't have any DC on the mains feed. If not then continue your search for the right toroid to try. But if you have a dc offset on your mains, stick with the El configuration and you'll be much happier in the end.
I've used Anteks with no problem in several builds. They're powering my current preamp. Despite the 115 primary rating, they are designed to produce specified voltages at 120VAC. They were inexpensive but I don't know know how the new tariffs will affect the prices. I've never had a problem with DC offset but you can buy DC blocker kits.
Thank you.
Dc on my mains feed is irrelevant because what i am building needs to be able to plug in anywhere i decide to take it... thanks for that.
How common is dc on the line?
Seems like it would cause all sorts of problems...
Good to know.
Not to mention millions of other non-audio devices that have toroids, and they don't buzz and overheat. This is non issue.
Does Antec use copper wire for winding their torroid transformers?
I once got bamboozled by some charlatans selling copper coated aluminum wire and vowed never to let that happen again...
I'm building at least 4 of these so 2 transformers are not going to cut it.
Also my intended B+ is 650 to 700 volts dc. It'll be difficult to get the power I'm after without at least 600v on the plates. I'd like these to be capable of delivering 100w of power midband, and the 430 transformers should do the job. The intent is to have a multi channel PA rig which i can use to dj shows at a local Jamaican restaurant. Back in the 70s in Jamaica the djs would build massive walls of speakers and massive tube bass amplifiers and throw big dances in the streets.
I'm going to build a pa rig in that style but which is serviceable in the modern era. 4x 6550 push pull amps for subs and 4 or 6 more 6bq5 channels for monitoring and remote speakers...
All in all it would be nice to have a 10 channel rig which can be configured to the venue and which I can DJ through without any squalid state components mucking with my sound.
I once got bamboozled by some charlatans selling copper coated aluminum wire and vowed never to let that happen again...
I'm building at least 4 of these so 2 transformers are not going to cut it.
Also my intended B+ is 650 to 700 volts dc. It'll be difficult to get the power I'm after without at least 600v on the plates. I'd like these to be capable of delivering 100w of power midband, and the 430 transformers should do the job. The intent is to have a multi channel PA rig which i can use to dj shows at a local Jamaican restaurant. Back in the 70s in Jamaica the djs would build massive walls of speakers and massive tube bass amplifiers and throw big dances in the streets.
I'm going to build a pa rig in that style but which is serviceable in the modern era. 4x 6550 push pull amps for subs and 4 or 6 more 6bq5 channels for monitoring and remote speakers...
All in all it would be nice to have a 10 channel rig which can be configured to the venue and which I can DJ through without any squalid state components mucking with my sound.
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https://www.antekinc.com/as-8t650-tube-amp-transformer/
I like that Antek typically has dual secondaries, HV and LV, so it's easy to do dual mono builds. Or wire em parallel for more current. Sounds like that's right up your alley.
I like that Antek typically has dual secondaries, HV and LV, so it's easy to do dual mono builds. Or wire em parallel for more current. Sounds like that's right up your alley.
The 430V is the right one for a 600V supply and 100 watts per channel. I used two in parallel for each 200W monoblock. Depending on your OPT you might go to 700 V, with the 475V unit. Higher impedance needs more voltage.
The 650V unit would give 1300 VCT. Transmitter tube territory, not for 6550’s. Some sweep tubes would work ok with that, but they all require a sub-200V screen supply.
The 650V unit would give 1300 VCT. Transmitter tube territory, not for 6550’s. Some sweep tubes would work ok with that, but they all require a sub-200V screen supply.
Is Antec just a Chinese transformer re-boxed and sold in USA?
Their website gives their address but no made in______. Sort of info so one is left to assume.
I've got a few companies to look into but I think Antec is out due to being ambiguous about their products origin.
A similar thread on a different site yielded a few stateside manufacturers to look into.
Their website gives their address but no made in______. Sort of info so one is left to assume.
I've got a few companies to look into but I think Antec is out due to being ambiguous about their products origin.
A similar thread on a different site yielded a few stateside manufacturers to look into.
I order Toroidy from TME in Europe only $9 flat rate shipping, no VAT, no tariff, shipped to Lockport IL in about 4 days. If TME is not stocking the model you need, Toroidy is very easy going to get you the part at lowest cost.
There are always US manufacturers to look into, but I doubt anyone will meet/beat Antek for the price. They aren’t like fake 2SC5200’s that blow up when you try to make amplifiers out of them - they work as well or better than ones in most consumer product and give no trouble at all. If you are going to avoid them on principle - that’s of course your choice, but don’t run scared worried about quality. A lot of us use them. Can you get better? Sure. For an amplifier that I’m going to DJ with? They are good enough. The shielded ones are butt-ugly, but none of my creations is ever going to win a beauty contest anyway.
The tariffs will make EVERYBODY’s prices go up - even made in USA, because the supply chains are global. Where does the copper come from? Not here.