It's nice to see someone else figured out how to use a tap! Yes the drilling process is very important for the tapping process. I do mine in a milling machine. I have yet to find good quality thread rolling taps in my area though.
Nice. What type of machine?
Yes, Fronius TIG welder
I bought my first about 17 years ago and it is still going strong! It's one of those things that although not cheap, is certainly good value 😉
For SA2014 I use even higher VAS current: ~ 17mA. 2 stage EF OPS need more current from VAS in comparison to 3 stage EF OPS.
Don't know if this is "too high". My total LTP current is also very high - 6mA.
This allows me to use bigger compensation capacitors (easier to get) and reduce dependency of stray capacitance's.
BR, Toni
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Depends on speaker loading.
Assuming a 3pair output stage:
I'd suggest dual 35Vac for 4ohms. Dual 40Vac for 6ohms and dual 45Vac for 8ohms.
If you're using very high SOA transistors, then you may find you can increase the transformer voltage by one step:
dual 40Vac for 4ohms, dual 45Vac for 6ohms and dual 50Vac for 8ohms, with 4302/4281 and with very good cooling.
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SA2014 is designed for 8 ohm speakers using 2x50VAC transformers, 550 - 650 VA.
SOA safe with good cooling also for 4 ohm speakers so you can bridge it for 800 W @ 8 ohm speakers.
BR, Toni
SOA safe with good cooling also for 4 ohm speakers so you can bridge it for 800 W @ 8 ohm speakers.
BR, Toni
I have an old Bridgeport that was retired from a near by factory that used to produce satellite parts.
The question is: what are the rails under a load of e.g. 200W, 8ohm. At least +-60VDC are necessary.
Yep! With +/-60VDC you get exactly 200W8R or 400W4R. That was the max. supply voltage of my test bench. With 600VA transformers the max. power below 1% THD20k was due to rail voltage sagging about 220W8R.
BR, Toni
BR, Toni
I assume 60V is the DC voltage at loading caps while 200W/8ohm. What is your transformer AC voltage, how many uF's do you use?
No. The +/- 60V are from my 2 regulated PS maximum setting (per PS 2x30V in serial configuration).
If you use the described 650VA transformer and the big SA2014 PS pcb the rails are sagging to 62 - 65V if you play 220W continous. One monoblock PS uses 8 x 10000uf/100V lytics.
If you use the described 650VA transformer and the big SA2014 PS pcb the rails are sagging to 62 - 65V if you play 220W continous. One monoblock PS uses 8 x 10000uf/100V lytics.
Hello Toni. I always find good suggestions in your post. What did you pay for the TAUSCHER-transformer? I suppose that was 1 piece? Is there a hum to hear? Since it is shed, is there any smell? Presumably it will not have primary / secondary shielding.
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I've ordered 6 pieces 600 VA custom made. Total cost incl. shipping was about 850 EUR. But you get them only B2B. Quality is very good. Mechanical hum only, if DC on AC line is present. No smell. Shielding can be ordered if wanted.
If you want B2C custom made transformery you can try toroidy.pl for example.
BR, Toni
If you want B2C custom made transformery you can try toroidy.pl for example.
BR, Toni
I have other experience: my custom made transformers in a stainless steel pot housing from toroidy.pl look very professional at a reasonable price. Maybe another company is able to deliver the same custom made transformers at a lower price. But we can discuss this in an extra thread where you can summarize all B2C toroid manufacturers.
BR, Toni
BR, Toni