Another DIY SS Amplifier with NVA Boards

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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 » Sat Mar 10, 2018 6:02 pm

How was your overall cost, did you end up with a bargain.

SteveTheShadow
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Re: Another DIY SS Amplifier with NVA Boards

Unread post by SteveTheShadow » Sat Mar 10, 2018 6:46 pm

Fifty quid for the case and about another thirty quids worth of components. The caps were the dearest electronic components of course, but yes a total bargain.

Thanks for giving me the opportunity to build with your boards.
I can tell you now after only a couple of hours burning in, it blows away most of the gear I've heard.

I know you don't agree with the power supply configuration, but I wanted to put a different spin, on things, otherwise I'd just have been copying. I found the twin rectifiers config I'm using, in Morgan Jones "Valve Amplifiers" where he gives it as an example of a power supply for use in a solid state amp.

"That feckin' figures, I hear you say. :lol:
DIY NVA amplification ( roughly equivalent to NVA A60) BTE Designs passive preamp, BTE Designs Lenco L75 turntable, Rega R200 arm, Goldring E3 cartridge, NVA Phono 1
Musical Fidelity M1 DAC, AppleTV4 with Apple Music subscription, ripped CDs streamed via WD MyCloud Home Duo NAS, with PLEX media server.
Speakers - Large sealed cabs, with Fane 12-250-TC 12" full range drivers.

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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 » Sat Mar 10, 2018 7:20 pm

If it works it works.

SteveTheShadow
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Re: Another DIY SS Amplifier with NVA Boards

Unread post by SteveTheShadow » Sat Mar 10, 2018 10:52 pm

Review

The word that keeps coming up, with everything I'm playing, is "Authority"
This amp is effortless on my omnis. It takes whatever I throw at it and just plays without fuss or favour.
The presentation is very detailed, but never hard nor nasty, no matter how complex the mix gets, which means that it digs right into the core of the music and brings it out into the room.

Because I use omni speakers, it means I am into the "they are here" aspect of hi-fi rather than "you are there" and this amp certainly brings the music into the living room with aplomb. The top end is clear as a bell, utterly devoid of any hardness, fizz or grain and deals with all the subtle and complex percussion details of Latin jazz with a deft assuredness that is captivating.

Cymbals shimmer, rivets rattle, hi-hats tsssk, like live ones do. Shakers shik-a-shik and bongos start and stop on a dime....lovely.

The bass performance is detailed, fast and goes as deep and powerful as my speakers will go. The amp would certainly shift some air if it were connected to a set of 12" drivers.

Through my own speakers, electric bass plays tunes way down, whilst maintaining the attack of finger or plectrum on strings. This is particularly good on Bert Kaempfert, where he often uses an acoustic bass and plectrum played electric bass at the same time. The amp makes it easy to tell which is which, without the acoustic bass becoming lost in the proceedings...again lovely.

In the midrange, vocals are correct, with no nasality on females or hardness on black male singers of the Levi Stubbs and Dennis Edwards variety. Electric guitars, bark and growl and are beautifully textured, with the creamy distortion generated by Marshalls and Fenders, coming over unsullied. Big band brass blares convincingly, again with a subtlety and lack of distortion, that makes it very easy to turn the wick up to high levels without the music becoming conjested or muddy.

Nothing stands out and everything hangs together like few amps I've heard. I'm loving what it does.
DIY NVA amplification ( roughly equivalent to NVA A60) BTE Designs passive preamp, BTE Designs Lenco L75 turntable, Rega R200 arm, Goldring E3 cartridge, NVA Phono 1
Musical Fidelity M1 DAC, AppleTV4 with Apple Music subscription, ripped CDs streamed via WD MyCloud Home Duo NAS, with PLEX media server.
Speakers - Large sealed cabs, with Fane 12-250-TC 12" full range drivers.

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karatestu
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Re: Another DIY SS Amplifier with NVA Boards

Unread post by karatestu » Sun Mar 11, 2018 10:03 am

Morning Steve,

I wonder how late you stayed up last night :guiness;

Funny how we both picked up on similar things when first commenting on these amps. We both know how well nva and semi omni speakers replay old jazz (blue note in my case) :dance: We both picked up on shimmering cymbals and brass instruments.

Enjoy :grin:
Naim, Linn & Harbeth fanboy

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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 » Sun Mar 11, 2018 10:59 am

It is still new Steve it has a fair amount of run in to do yet. Main benefit will be mostly bass clarity and tune playing. Just leave it switched on for run in. Take speaker leads out if worried (one per side).

SteveTheShadow
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Re: Another DIY SS Amplifier with NVA Boards

Unread post by SteveTheShadow » Sun Mar 11, 2018 12:19 pm

OK will do that.
Thanks.
DIY NVA amplification ( roughly equivalent to NVA A60) BTE Designs passive preamp, BTE Designs Lenco L75 turntable, Rega R200 arm, Goldring E3 cartridge, NVA Phono 1
Musical Fidelity M1 DAC, AppleTV4 with Apple Music subscription, ripped CDs streamed via WD MyCloud Home Duo NAS, with PLEX media server.
Speakers - Large sealed cabs, with Fane 12-250-TC 12" full range drivers.

SteveTheShadow
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Joined: Thu Sep 12, 2013 5:24 pm
Location: S Yorks
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Re: Another DIY SS Amplifier with NVA Boards

Unread post by SteveTheShadow » Sun Mar 11, 2018 1:33 pm

In my post further back about reading up on SS power supplies, here is the most helpful one I found and takes you through all the bits you need to know about when designing. I reckon Morgan Jones might have given an example from here as an illustration of a transistor amp power supply, given the date of the paper (2000). It's a long article in three parts but worth reading IMO.

http://www.tnt-audio.com/clinica/ssps1_e.html
DIY NVA amplification ( roughly equivalent to NVA A60) BTE Designs passive preamp, BTE Designs Lenco L75 turntable, Rega R200 arm, Goldring E3 cartridge, NVA Phono 1
Musical Fidelity M1 DAC, AppleTV4 with Apple Music subscription, ripped CDs streamed via WD MyCloud Home Duo NAS, with PLEX media server.
Speakers - Large sealed cabs, with Fane 12-250-TC 12" full range drivers.

Lurcher300b
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Re: Another DIY SS Amplifier with NVA Boards

Unread post by Lurcher300b » Sun Mar 11, 2018 1:50 pm

What it doesn’t cover is the benefit that adding a 1uf film cap across each capacitor (or at least the last ones) can give.

SteveTheShadow
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Re: Another DIY SS Amplifier with NVA Boards

Unread post by SteveTheShadow » Sun Mar 11, 2018 2:05 pm

Lurcher300b wrote:
Sun Mar 11, 2018 1:50 pm
What it doesn’t cover is the benefit that adding a 1uf film cap across each capacitor (or at least the last ones) can give.
Hmmmm....... :)
DIY NVA amplification ( roughly equivalent to NVA A60) BTE Designs passive preamp, BTE Designs Lenco L75 turntable, Rega R200 arm, Goldring E3 cartridge, NVA Phono 1
Musical Fidelity M1 DAC, AppleTV4 with Apple Music subscription, ripped CDs streamed via WD MyCloud Home Duo NAS, with PLEX media server.
Speakers - Large sealed cabs, with Fane 12-250-TC 12" full range drivers.

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