Re: Another DIY SS Amplifier with NVA Boards
Posted: Sat Feb 12, 2022 10:57 pm
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Another DIY SS Amplifier with NVA Boards
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Re: Another DIY SS Amplifier with NVA Boards
Posted: Sat Feb 12, 2022 11:15 pm
let me help you Stu ;]
Re: Another DIY SS Amplifier with NVA Boards
Posted: Sun Feb 13, 2022 8:47 am
Thanks Rex and Tomasz.
Modern boards don't have polystyrene caps - red Wima film. Time to get the soldering iron out
Modern boards don't have polystyrene caps - red Wima film. Time to get the soldering iron out
Re: Another DIY SS Amplifier with NVA Boards
Posted: Fri Apr 01, 2022 9:09 am
I am also working on some NVA boards. I also want to try separate PSU for end and mid boards. I do not wan't to go with dual mono for my own reasons.
I have AP50 boards and a spare original NVA Rs 30v 160va transformer that i want to use with an extra bridge and caps. I know that NVA now uses 25v and that with older intergrated amps 30v for the output transistors and 25v for main board.
So, is there any objection against using two dual 30v power supplies for the NVA boards in this set-up?
With one 30v as in the original NVA AP50 the whole board gets the same 30v (before rectification) voltage anyways?
I have looked at the parts and one one or two 47uf caps needs to go to 50v.
I have AP50 boards and a spare original NVA Rs 30v 160va transformer that i want to use with an extra bridge and caps. I know that NVA now uses 25v and that with older intergrated amps 30v for the output transistors and 25v for main board.
So, is there any objection against using two dual 30v power supplies for the NVA boards in this set-up?
With one 30v as in the original NVA AP50 the whole board gets the same 30v (before rectification) voltage anyways?
I have looked at the parts and one one or two 47uf caps needs to go to 50v.
Re: Another DIY SS Amplifier with NVA Boards
Posted: Fri Apr 01, 2022 10:54 am
Our engineer, Tomasz, will be happy to have a conversation with you about what you are planning...but he is occupied full time for the next 10 days or so with building orders and replenishing stock. You could drop him a line here, by PM, in a week or so. His user name is Ithilstone.Adewitte wrote: ↑Fri Apr 01, 2022 9:09 am I am also working on some NVA boards. I also want to try separate PSU for end and mid boards. I do not wan't to go with dual mono for my own reasons.
I have AP50 boards and a spare original NVA Rs 30v 160va transformer that i want to use with an extra bridge and caps. I know that NVA now uses 25v and that with older intergrated amps 30v for the output transistors and 25v for main board.
So, is there any objection against using two dual 30v power supplies for the NVA boards in this set-up?
With one 30v as in the original NVA AP50 the whole board gets the same 30v (before rectification) voltage anyways?
I have looked at the parts and one one or two 47uf caps needs to go to 50v.
Hope this helps. Warm regards,
Paul
Re: Another DIY SS Amplifier with NVA Boards
Posted: Fri Apr 01, 2022 11:56 am
Thanks Paul for the service,
Wil drop hem a line. Wil be interesting.
Wil drop hem a line. Wil be interesting.
Re: Another DIY SS Amplifier with NVA Boards
Posted: Fri Apr 01, 2022 9:48 pm
30V is well within the capability of the circuit and 50v or even 63v caps are better parts anyway, used at any voltage (< rating), IME.Adewitte wrote: ↑Fri Apr 01, 2022 9:09 am So, is there any objection against using two dual 30v power supplies for the NVA boards in this set-up?
With one 30v as in the original NVA AP50 the whole board gets the same 30v (before rectification) voltage anyways?
I have looked at the parts and one one or two 47uf caps needs to go to 50v.
I don't recall any of the electrolytics on the board being exposed to the rail voltage though... Tomasz?
Re: Another DIY SS Amplifier with NVA Boards
Posted: Tue May 10, 2022 10:27 pm
Over the last few days, the amp has had a bit of an internal and external facelift. I retrieved my old Khozmo 10K shunt stepper and an Elma 3 position rotary switch from our Ant’s place and did an internal refresh, incorporating the attenuator, and switch onto the front panel and moving the phono board to the internal side wall. Regulator for the phono board sits between the two amp boards:
Reworked the front panel to take two control knobs and moved the LED on indicator to the other end of the panel. Gave the front a re-wax and there you go.
From a distance with the Pat Metheny Group on the turntable:
Niiice. 
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Re: Another DIY SS Amplifier with NVA Boards
Posted: Wed May 11, 2022 9:44 am
Love the front panel
Re: Another DIY SS Amplifier with NVA Boards
Posted: Wed May 11, 2022 10:07 am