Another DIY SS Amplifier with NVA Boards

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SteveTheShadow
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Re: Another DIY SS Amplifier with NVA Boards

Unread post by SteveTheShadow »

Everything in my system is referenced to earth. I'm used to extreme safety measures given the high voltages I usually play with.
We'll see if there is any hum once I get it in the system.
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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 »

How thick is that base plate, it seems to me you are under heatsinked.

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SteveTheShadow
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Re: Another DIY SS Amplifier with NVA Boards

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4mm
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SteveTheShadow
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Re: Another DIY SS Amplifier with NVA Boards

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It's all working and is currently soaking on test.
Image

Gentle hiss with ear to each speaker.

Devices only slightly warm to the touch, although it is of course only idling.
Mains transformer very quiet.

I'll try it on some music shortly.
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Re: Another DIY SS Amplifier with NVA Boards

Unread post by Dr Bunsen Honeydew »

You are under heatsinked for that voltage. No problem normally but 4 ohm or difficult loads and played loud then it will get very hot, maybe too hot. For you if it is just your speakers just keep an eye (hand) on temp. For a production unit I would have used a proper heatsink not just a plate, unless bloody enormous like Stu's one.

Smaller voltage less VA as with the A20 then a plate is fine.

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SteveTheShadow
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Re: Another DIY SS Amplifier with NVA Boards

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Thanks Richard.
I'm only intending to use it as a low power amp like the A20. I'm only using 25V secondaries as I wasn't in the end, prepared to fork out for transformers until I was sure I wasn't going to blow the things up so I used a toroid I found in one of my boxes. I did however fork out for a nice case; a case of arse about face priorities maybe? - go figure :lol:

Now I know what I'm doing (sort of) I could easily up the power, monoblock it and put it in a pair of whacking great heatsinked cases. A new set of output devices and boom! (not literally I hope)
Last edited by SteveTheShadow on Sat Mar 10, 2018 4:56 pm, edited 1 time in total.
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Re: Another DIY SS Amplifier with NVA Boards

Unread post by Dr Bunsen Honeydew »

Maestro - music please!

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Re: Another DIY SS Amplifier with NVA Boards

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Dr Bunsen Honeydew wrote: Sat Mar 10, 2018 4:56 pm Maestro - music please!
There you go.
Image

Been going for about 15mins
Bloody hell, this is good 8-)
I'll run it up for an hour and check the devices' temperatures
Once that's done, I just need an LED and resistor fitting and the front panel and top plate.

Review later.
Last edited by SteveTheShadow on Sat Mar 10, 2018 5:14 pm, edited 1 time in total.
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Re: Another DIY SS Amplifier with NVA Boards

Unread post by karatestu »

Nice one Steve :guiness;

I bet i know what you will be doing tonight :dance:
DIY FREE ZONE

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SteveTheShadow
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Re: Another DIY SS Amplifier with NVA Boards

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Aye, there'll be a bit of listening and appreciating.

Finished job, complete with LED indicator:
Image

That was fun. I'm doing the snapbackjack, stimulator, alligator! :dance:
Somebody’s telling me the latest scandals.
Somebody’s stepping on my plastic sandals. Joe Jackson (1979)

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