Got the PIO's matched: 3,94uF and 3,95uF.
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An externally hosted image should be here but it was not working when we last tested it.
Sorry I've come in late to this thread, been off the forum for a while due to ill health. I have these you could have had...
All the TDA 1541A's are original, sourced from Philips many years ago for my now defunct Cambridge CD2...don't know where the 4th chipset is, or the upgraded SAA7220.
These are the CD2 originals....
Ian
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
All the TDA 1541A's are original, sourced from Philips many years ago for my now defunct Cambridge CD2...don't know where the 4th chipset is, or the upgraded SAA7220.
These are the CD2 originals....
An externally hosted image should be here but it was not working when we last tested it.
Ian
Hi Evilbat,
What are the circuits in the first pic for? Parallelling TDA1541A's?
Shoot me a PM with what you want for the TDA1541A's and also the two circuits.
What are the circuits in the first pic for? Parallelling TDA1541A's?
Shoot me a PM with what you want for the TDA1541A's and also the two circuits.
Started putting the ECC86 output in to the box...not looking pretty now, hopefully it will when I'm done.
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Bigger may well be better, but 18V is not bigger than 20V.
Common toroidal mains transformers in particular may be on the edge of saturation if not sufficiently loaded. Certainly they'll tend to produce more odd-order mains harmonics because they'll be pushed into the wriggly part of the relationship between flux and current.
As a rule, don't use transformers with higher voltages than intended on any winding. Over-voltage eats low frequencies.
Generally, if you compare equally well-specified transformers with materials of equal quality, bigger will be better. That's one big reason why good stuff is heavy, and most valve amps can be dismissed at a glance.
Ian
I think the comment quoted above was ment for VA, not V.
And it was also ment as an attempt at humor. I honestly thought that a 200VA toroidal was atleast as good as a 20VA provided Voltages were the same. I've never built dac's before but several amps, and when it came to PS went as big I could afford.
And it was also ment as an attempt at humor. I honestly thought that a 200VA toroidal was atleast as good as a 20VA provided Voltages were the same. I've never built dac's before but several amps, and when it came to PS went as big I could afford.
Mayday, МБГОs are not exactly PIO, but PIW (Paper in Wax). You can open one from it's metal casing and take a look. I can recommend getting rid of the steel casing anyway and put an organic (paper, wax, wood) case, fill it with wax and seal it with resin. The sound really does improve with these cheap babies, I use them for power supplies.
Made some progress on the tube output today. Not sure I'll have time for more work today...
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The problem is, many people mistake them for PIO, even I did. They are very good for the price I think, but you really should get them out from the metal casing. I use a dremel to cut it. The terminals are a little PITA, they eat the cutting discs pretty fast, because they're made of glass.
I get them for real cheap and I get use to replace the electrolytics in a PSU 🙂
My advice is - listen first with their metal casing on, then try to remove it and listen again.
I get them for real cheap and I get use to replace the electrolytics in a PSU 🙂
My advice is - listen first with their metal casing on, then try to remove it and listen again.
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Thanks for the heads up 🙂
I'll keep them as is for now, maybe you can tell me wich russian caps that are actual PIO's ?
I'll order proper ones later then. I need about 4uF pio's. And space is starting to become an issue in the box.
I'll keep them as is for now, maybe you can tell me wich russian caps that are actual PIO's ?
I'll order proper ones later then. I need about 4uF pio's. And space is starting to become an issue in the box.
A great for the price russian PIO is К40-У9. I'm not sure if you can find it in big capacities though. It's in a metal casing and I remove it as well, then I put it in heat shrink tubing and seal both ends with sillicone. It sounds awesome for the money.
K40-U9
http://www.ebay.com/sch/i.html?_from=R40&_trksid=m570.l2736&_nkw=K40U9
Removing the casing of these is a piece of cake. I can give you details if you need.
K40-U9
http://www.ebay.com/sch/i.html?_from=R40&_trksid=m570.l2736&_nkw=K40U9
Removing the casing of these is a piece of cake. I can give you details if you need.
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I've had those as well as some axial Green ones. I think they can handle high voltages, but I doubt they go very high in capacitance?
Hi Jonas, Take your time on the tube stage. Don't rush and avoid errors. 🙂 Interesting on the Russian PIO's.... Dave
Hi Dave,
I will take my time, and I'll test all conections twice before putting in a tube and powering it up.
Jonas
Soldered the 47R/47nF-filters to the I/V-resistors.
Also soldered the wire that'll go to signalgnd, left to do is solder wire from TDA1541A out to I/V-resistors and from I/V-resistors to Grid(with gridstopper between).
Also soldered the wire that'll go to signalgnd, left to do is solder wire from TDA1541A out to I/V-resistors and from I/V-resistors to Grid(with gridstopper between).
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An externally hosted image should be here but it was not working when we last tested it.
Will do Dave.
The AMRG should be the best of the bunch, but I also have Holco H2's 50R and Dale 50R(on the way).
Jonas
Got some more work done on the tube output.
Soldered both supplies to one 4-pin connector and soldered connectors to the I/V-resistors.
Soldered both supplies to one 4-pin connector and soldered connectors to the I/V-resistors.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
A first idea about how to place I/V-resistors and filter.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
