You can by twisting wire between board as holes are at same place in each IPS /OPS
After some more soldering job......Board are up to 95% complete because those parts need to be on heatsink as Output BJT, sanken driver, rectifier diode. I have to build 2uH self. I need to link on NS-OPS board left side to rigth side 0V
Marc
Marc
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Just great work ! 
I'm upgrading mine but already sounding fine with every preamp I connected it with.
What kind of transformer are you using ? (volts and amperes)
I'm upgrading mine but already sounding fine with every preamp I connected it with.
What kind of transformer are you using ? (volts and amperes)
Thanks savvas,
The big ones are Talema 500VA 2x35Vac(2x7.1A)
And the little ones are Talema 15VA 2x15Vac(2x0.5A)
The big ones are Talema 500VA 2x35Vac(2x7.1A)
And the little ones are Talema 15VA 2x15Vac(2x0.5A)
Thanks for the info. I too have 35VAC big trannies (it's about 100W / 8Ω) and was told by the boys that it performs better delivering 160-220W.
So buying a new trannies was first on my list but then I've decided to finish two preamp projects to test them at last with this amp. Holy smoke, they play to the level it needs serious auditions to decide. For the moment, I've upgraded to separate trans for front end and double up the capacitor bank. Definitely I'm gonna go for higher voltage, probably 42VAC, so I can use 63V main capacitors
I'm wondering if anyone here tried the new psu for front end.
So buying a new trannies was first on my list but then I've decided to finish two preamp projects to test them at last with this amp. Holy smoke, they play to the level it needs serious auditions to decide. For the moment, I've upgraded to separate trans for front end and double up the capacitor bank. Definitely I'm gonna go for higher voltage, probably 42VAC, so I can use 63V main capacitors
I'm wondering if anyone here tried the new psu for front end.
I've just noticed that you have the same chassis plan as mine. Heatsinks enclosed I assume. My plan too has the trannies at the bottom. Any particular reason you've chosen r-cores ?
My first build has 40Vac transformers. I do not hear any difference. You have to change some resistors on dc protection and also in VAS when you go higher voltage.
The reason is simple : i bougth them about 15years ago for 25€ each instead 110€ each during sales
Marc
The only difference I've found by using the new regulator board for the input is a slight boost in output power due to no supply sag. Noise and distortion levels are unchanged, the PSSR of the input stages is excellent, so a quieter supply doesn't really make a difference there.
Yeah, Valery already told me but I always appreciate first hand experience of others. Many times in my system I hear differences in parts that others don't experience
And another thing with the new regulator boards is the ability to place the regulators and main cap bank near front end and OPS respectively.
I don't remember who of the two mentioned it, that amp sounds better with bigger psu (output 160-220W) so I thought of 42VAC. Are the differences substantial ? In this scenario do I need to change anything in OPS and protection board as @filenet mentioned. I vaguely remember remember in email we exchanged that I don't
That's explains it. I'm in no hurry replacing my existing trannies but I wanted to know if it was worth buying r-cores if opportunity appears (I'm not gonna order ones from China)
I don't think any changes are necessary to run with 42VAC transformers. That should give you around +/- 60V supplies which is around the lower end of the voltage range they were designed for.
The improvement with higher supply voltages depends on you source and how loud you play it, and your speaker efficiency. With a good source it's actually quite easy to clip an amplifier, which almost never sounds good. I've had quite a few arguments that tweeters sound better when the amp has a higher voltage supply, and clipping is likely why I've found this. Bob Cordell has a good paper on amplifier power supplies. http://jipihorn.free.fr/Documents/Divers Blog/Cordellinterview.pdf
The improvement with higher supply voltages depends on you source and how loud you play it, and your speaker efficiency. With a good source it's actually quite easy to clip an amplifier, which almost never sounds good. I've had quite a few arguments that tweeters sound better when the amp has a higher voltage supply, and clipping is likely why I've found this. Bob Cordell has a good paper on amplifier power supplies. http://jipihorn.free.fr/Documents/Divers Blog/Cordellinterview.pdf
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I play music at low to average sound levels but my speakers have low impedance (4Ω) and low sensitivity (86db) so more power is always welcomed
I have the limitation of 63V caps (main bank) and taking into account the voltage swings of the AC line, I chose 42VAC (not ordered yet). I haven't seen anywhere (thread or manuals) any discussion of rail voltage / output power and I only decided to upgrade to bigger toroid when you suggested that in one of your emails (great support always).
Before sometime I was wondering how the tube preamp was going but l put another two preamps on the rank and they play surprising very good, hard to decide and it's time consuming too. So progress of putting it into chassis is moving slow.
I have the limitation of 63V caps (main bank) and taking into account the voltage swings of the AC line, I chose 42VAC (not ordered yet). I haven't seen anywhere (thread or manuals) any discussion of rail voltage / output power and I only decided to upgrade to bigger toroid when you suggested that in one of your emails (great support always).
Before sometime I was wondering how the tube preamp was going but l put another two preamps on the rank and they play surprising very good, hard to decide and it's time consuming too. So progress of putting it into chassis is moving slow.
I usually use a 40VAC transformer with 63v capacitors.
Off load sometimes the transformer output can be a little high.
Also mains voltage fluctuations need to be taken into account.
Off load sometimes the transformer output can be a little high.
Also mains voltage fluctuations need to be taken into account.