Hi LC,
This week Nbip3 (alias brother of quasi) is born ( http://www.diyaudio.com/forums/solid-state/88258-brother-quasi-44.html#post3224050 ), that's done i can yet go foward on TSSA BIGBT HP. I will not have time in the evening so saturday or sunday i will go on CCSs test.
I have to purchase new filtering/smoothing caps (this i have are old used one....). Have you an advice on µF amount per chanel?
Marc
This week Nbip3 (alias brother of quasi) is born ( http://www.diyaudio.com/forums/solid-state/88258-brother-quasi-44.html#post3224050 ), that's done i can yet go foward on TSSA BIGBT HP. I will not have time in the evening so saturday or sunday i will go on CCSs test.
I have to purchase new filtering/smoothing caps (this i have are old used one....). Have you an advice on µF amount per chanel?
Marc
Hi Idefixes,
Nice work. Hope your build went well. You took the audio ground from the wrong point.
A single device is the purest amplifier. Thus the fewer the devices, the better. Keep It as Simple as Possible.
In the hunt for lower THD and DC to light performance we may put together many devices, it works sometimes.
A situation where many devices work together to reduce THD due to random noise cancellation exist, such as used by Self paralleling Op Amps.
Listening Tests are strange things that leave us with even more questions whether something is worth it or not. Thus the refusal of tube gear to die out.
Thank you for your continued contributions to audio.
kind regards,
Harrison.
Yes. I think THD is not a useful concept. Nowadays I don't even look at the THD number in LTSpice. I simply print the FFT from 0v1 to 0v7 or more (up to 2v). From the chart you can see if 0v1 will give higher distortion than 0v2. Or you can see how distortions move with input voltage increase. And many more.
Nice new amp you have there. TSSA will follow soon. I also li 63v
ke to have more amps in the house, a lot of posibilities to explore, compare, improve, to learn and above all to have fun.
For good smoothing I suggest you from 40 to 60 mF per channel.
Ok thanks, i will go for 4x 15.000uf
Marc
From some regular ELCO producer or more audiophile type?
BTW, you don't know what you're missing ...
Some Rubycon MXR 15000uF 63V that we can found on ebay. I am not an "audiophile" product fan ... in french we said "idiophile" as adiot audiophile....
Marc
Just look at the data/price of each: I prefer paralleling little ones to divide serial inductances and resistance.
Have-you tried my stabilized one ? (big caps before Ballasts, parallel after).
LC: i wonder if we can try to study a constant current soft start based on some triac.
We can do all settings with TSSA PCB without waiting to those Rubycons to arrive. BTW those ELCOS have really high riple current value, nice
I have what i need to do setting test but i missing time for moment. I just transfer last week hifi devices to dedicated room that i was building in my basement house.
Marc
NTC suits the need well enough. Maybe it would be better to have inrush current sensing with comparator to turn on the triac when current falls to 20% or so.
Super
I see you're occupied as well as me lately, anyhow TSSA will give you more insights when operating.
Super
I see you're occupied as well as me lately, anyhow TSSA will give you more insights when operating.
No doubt,
I have put backside a second stereo BIGBT combination for another amp project as i have on hand two other nice 500Va 2x36V rcore trafo or two 300Va 2x24V.as some more various heatsink.
Marc
My idea was to use a time dependent ramp to fire the Triac, starting at the end of each AC half sinus, and slowly firing the triac up to its beginning as charging time increase (100%). AS top of he sinus will be half the time, even with a simple RC, we have the chance to set a near linear peak current for charging the caps,, just to change the time constant of the amp, to tune-it for different caps values of the PSU.NTC suits the need well enough. Maybe it would be better to have inrush current sensing with comparator to turn on the triac when current falls to 20% or so.
Marc, so now you have eight BIGBTs all together ready to go. Very good, for me personally I consider BIGBT as one transistor only because it acts like one, no oscillations, no problems with it whatsoever, it is powerfull, high current capability and high transconductance enables VAS to breathe with full lungs.
Hardly wait to start with your TSSA BIGBT.
My CSA is ready, just waiting to get heatsinks from CAD CAM company.
Hardly wait to start with your TSSA BIGBT.
My CSA is ready, just waiting to get heatsinks from CAD CAM company.
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I don't like at all those high temp of NTC or resisatence during start-up. EMI is not an issue; it is only during some seconds at start-up. But i understand the simple and easy way.
You do not answered my question about stabilized . Did-you have made the listening test ?
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