Another DIY SS Amplifier with NVA Boards

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valvesRus
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Re: Another DIY SS Amplifier with NVA Boards

Unread post by valvesRus »

Dr Bunsen Honeydew wrote: Fri Mar 16, 2018 10:33 pm Are you like Steve do you build your own valve gear.
Yes, I have built a few valve amps in the past, but not up to the standard of Steves latest creation.

Trouble is with valves, good ironware is so expensive if you want the results to sound better than average and the pension won't run to it.

I've still got a few boxes full of components to play with though. :)

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Dr Bunsen Honeydew
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Re: Another DIY SS Amplifier with NVA Boards

Unread post by Dr Bunsen Honeydew »

What system do you use.

valvesRus
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Re: Another DIY SS Amplifier with NVA Boards

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Dr Bunsen Honeydew wrote: Fri Mar 16, 2018 11:25 pm What system do you use.
I downsized a few years ago, but my current system is a KT66 push pull amplifier, a Denon old style heavyweight DVD player (for CDs), an Ebay AK4396 DAC kit and some Frugal horn single driver full range speakers.

It gels quite well in my room but I know the amps are the weak point, followed by the speakers.

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Dr Bunsen Honeydew
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Re: Another DIY SS Amplifier with NVA Boards

Unread post by Dr Bunsen Honeydew »

I am willing to consider others for the DIY nva route but it would be my decision. Experience of amp DIY valve or solid state and basic knowledge and soldering and assembly skills, I want no fried up disasters. A willingness to talk us through the process as forum entertainment. Not a pro nva attitude but definitely not an anti me or nva attitude, or a cured one.

If interested convince me by PM.

Boards are £100 a pair with output devices.

valvesRus
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Re: Another DIY SS Amplifier with NVA Boards

Unread post by valvesRus »

Dr Bunsen Honeydew wrote: Sat Mar 17, 2018 1:21 pm I am willing to consider others for the DIY nva route but it would be my decision. Experience of amp DIY valve or solid state and basic knowledge and soldering and assembly skills, I want no fried up disasters. A willingness to talk us through the process as forum entertainment. Not a pro nva attitude but definitely not an anti me or nva attitude, or a cured one.

If interested convince me by PM.

Boards are £100 a pair with output devices.
Thanks Richard for the offer, it would be nice to test my DIY skills once more. :grin:

I'll do a few sums before I PM you.

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Dr Bunsen Honeydew
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Re: Another DIY SS Amplifier with NVA Boards

Unread post by Dr Bunsen Honeydew »

I don't think I made an offer, it is an ask for requests and to convince me you are up to it. Do it privately by PM.

valvesRus
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Re: Another DIY SS Amplifier with NVA Boards

Unread post by valvesRus »

A question please, regarding the power transformer.

I have a substantial 60v transformer with just two leads, if an 0v centre tap was created with two identical resistors would that be OK for the dual rail power supply ?

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Re: Another DIY SS Amplifier with NVA Boards

Unread post by Dr Bunsen Honeydew »

To be honest I don't know. The only way I know to put centre tap in would be to rebuild the transformer, so my instinct says no.

valvesRus
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Re: Another DIY SS Amplifier with NVA Boards

Unread post by valvesRus »

Dr Bunsen Honeydew wrote: Sat Mar 17, 2018 3:45 pm To be honest I don't know. The only way I know to put centre tap in would be to rebuild the transformer, so my instinct says no.
OK.

It's common in valve circuits for heater supplies.

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Re: Another DIY SS Amplifier with NVA Boards

Unread post by Lurcher300b »

valvesRus wrote: Sat Mar 17, 2018 3:50 pm
Dr Bunsen Honeydew wrote: Sat Mar 17, 2018 3:45 pm To be honest I don't know. The only way I know to put centre tap in would be to rebuild the transformer, so my instinct says no.
OK.

It's common in valve circuits for heater supplies.
Yep, but in the case of the heater you are not planing on pulling unbalanced current from either half (or much current at all). In the case of a power amp you would create a 0v of sorts but it would have to be a high impedance one (unless you used very small resistors in which case the dissipation in the resistors would be huge (and require a bigger transformer). You can get a 300va 30v+30v for £40, so not worth trying.

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