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  #1  
Old 20th January 2009, 11:42 PM
Nakman Nakman is offline
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Red face 5-20 received yesterday and revived toady

Hello - 1st post on this forum, with my arts degree and lack of knowledge you'll have too bear with my inability to understand the deep tech talk you are used too.

However this amp came to me via www.freecycle.org which we participate in as greenies. Its to stop unwanted item heading for the dump by giving them away for free thus recycling them.

Imagine my joy when amidst the baby carriers and IKEA furniture, x box games etc up came "2x 35 watt Hifi World monoblok valve amps -one is faulty may suit someone- needs new valve perhaps".

This was the maker himself so he knew well enough what he was offering. Like some here I was off like a shot and very effusive in my thanks.

Anyway after much polishing, joint checking valve swopping and minus a variac I got some help on PinkFish to come here and then switched on the good one. All seemed well with stability in glow and no smoke.

Used the good blok to check the valves from the 'faulty' one.

The valves are Sovtek EL 34g's/ 1 Golden Dragon EF86 1 CVC 86 & 2 generic (CVC ?) ecc83's.

It turned out the 2 amp fuse had blown! - I could not with my knowledge discern a cause for that but found the exact fuse in my drawer and switched on for a minute - all seems well behaved -

if this sounds reckless to anyone remember I was told it was faulty so I was not expecting so much good news.

So 20 years since I sold my ESL57's, Radford SCA-STA15 and Leak tl12 during a period when I was skint (no change there ) I can at last report that both my wife and I took barely 3 secs to grin and gnotice what was coming thru my b team speakers (little mission/denon things)

Indeed it was my wife who was in a rush to hear it and cleared surfaces to make space. Its been playing for 5 hours now with only a slight hiss in one channel at higher volume, otherwise stability.

The pre is a cobbled together pre out from a bog standard Denon cd.tuner amp but I have a Naim NAc 42 and 12s pre in the wings as well as the 32.5 if I dismantle the main system.

I have monoblokked Naim 110's into Isobariks as my main system and use various Nakamichis and a r300'd 401 nowadays far more than my Linn12 and Ittok and rega cd player which drives me nuts thru the Naims but fingers crossed for this new set up. I see I am slowly returning to an early days hifi

I will try the 5-20 in the 'briks soon enough but hardly expect synergy from that set up. Or does someone know oterwise?

My wife and I want to bring the main system back into the living room and out of my den, which means I can sell off quite a few components presently doubled up. This would surely include the briks (whose bass I love but prefer a better imageing really)

I cant use the spare Naim pre's until I cobble together a power supply for it (any ideas ?) as I only have one power supply for the brik system (a snaps).

Imagine it ending in the dump! Good heavens

I realise this is an ancedotal report but I welcome any views on what to aim for in a (penniless) pre or different valves or what to expect will be wearing out - its from 1993-4.

But you'll know that and has no later tweaks in it.

The maker also built the valve line level pre - and I might encourage him to sell that as I know he no longer has a power amp to play with - I should keep an eye on freecycle if I were you!
ian
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  #2  
Old 20th January 2009, 11:58 PM
andrew ivimey's Avatar
andrew ivimey andrew ivimey is offline
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Default Re: 5-20 received yesterday and revived toady

Well done, we all dream of this sort of chance happening. It hasn't happened to me but other good things have.

Its the right way to go!

I scoured freecycle and ended up giving lots more away, which is nice. And I got a lovely collectioin of VAl Doonican and some Classics for Pleasure, which although were in good condition, only a few of this label were worth having.
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  #3  
Old 21st January 2009, 10:00 AM
Mark Wood Mark Wood is offline
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Default Re: 5-20 received yesterday and revived toady

I built a pair of these in 1993 and they've been the only power amplifiers I've used ever since. (There's a photograph of them somewhere on another thread which I'll try to find later.) I've only ever had one problem and that was when an Edicron branded El34 failed rather spectacularly(!) and took the auto cathode bias components with it. (A smoking 10 W resistor is quite something to see!) Other than that, fingers crossed, no problems.
The valves I'm currently using are Sovtek EF86 and ECC83 and "large bottle" Electro Harmonix 6CA7 (EL34) output valves. I've no desire to change them for anything else which must say something.

Last edited by Mark Wood; 21st January 2009 at 10:31 AM. Reason: spelling mistake!
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Old 21st January 2009, 11:53 AM
Ali Tait's Avatar
Ali Tait Ali Tait is offline
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Default Re: 5-20 received yesterday and revived toady

Great story! So which WAD amps are they?
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  #5  
Old 21st January 2009, 12:09 PM
Richard Richard is offline
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Default Re: 5-20 received yesterday and revived today

Hi Ian,

Yes, a great story and very lucky

These were the HFW 5-20 monoblocs from 1993. Maplin did their 4-20 version the next year. Both used ss rects so I suppose they are both 4-20s really.

Re a cheap pre, sensitivity is 250mV so why not build a passive pre (pot in box) for your line sources so you'd just need a phono amp for vinyl. This can work very well.

The power amps should have a very good sound and would do justice to a WD3 phono and pre set-up long term.

Rich
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  #6  
Old 21st January 2009, 02:56 PM
Mark Wood Mark Wood is offline
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Default Re: 5-20 received yesterday and revived toady

Pictures of mine (hopefully) uploaded with this message. They're sporting my cobbled together wooden surrounds (nearly 16 years on and I still haven't made base plates for them). Sincere apologies for the carpet...

I initially used them with a Quad 33 which worked very well but now use a Velleman valve kit preamp which used to be sold by Maplin. It's still on the Velleman web site:

http://www.velleman.be/ot/en/product/view/?id=343035

and for what it cost as a kit (ca £200), it's remarkably good - apart from the terrible unbranded ECC82s that came with it.
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File Type: jpg HFW5-202.jpg (99.2 KB, 47 views)
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  #7  
Old 21st January 2009, 06:32 PM
Nakman Nakman is offline
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Default What price are these top flight Phillips Mullards?

Thanks very much - for the tips. Yes Mark I found your thread and subscribed to it looking for transformer covers as they clearly never arrived for this set either. Your box set up does look tidy but I hope for a more diminutive arrangement.

The existing Sovteks seem absolutely fine but I know I would like to hear some Phillips/mullard clones if not the other recommendations.EH's seem ceap enough. I have to say we are all in a state of musical bliss no matter what we play thru it - for which we are deeply grateful in these days and times - the better quality kit awaits but is at least a week away from being plugged in tho' due to hassle factors involved.

I only say this as it seems like recieved wisdom that the 'MULLARDS are it'. As I paid zero for the amps I wouldnt mind splashing out on disgracefully priced tubes - As I say first the naim pre's then the 'bariks' "then we take Berlin"

The pre languishing alone at the donors house will be under pressure from me first I expect.

Last edited by Nakman; 21st January 2009 at 06:36 PM. Reason: phyllosan shortage
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  #8  
Old 21st January 2009, 07:14 PM
Mark Wood Mark Wood is offline
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Default Re: 5-20 received yesterday and revived toady

Ah, the mythical transformer covers and side panels! The kits were (it appears) made up by a small UK hi-fi manufacturer and a price list came from them with the original instructions, advertising side panels and covers for the transformers and chokes. I duly sent off my cheque for the side panels and never heard anything back for months until I complained and finally got the cheque back with no explanation of what happened. By this time, the new K5881 kit had appeared and Hi-Fi World never really mentioned this kit again.

I very briefly tried some well used Mullard EL34s but ultimately settled on some very good Sovtek EL34gs as you have to make sure that I had a matching set. These lasted for 5 or 6 years and were followed by some superb nos GE 6CA7s (shown in the pictures) which came from Chelmer for £10 each - you can guess how long ago that must have been from that price! When one of them died, I replaced them with the identical-looking Electro Harmonix 6CA7s and I've been delighted with them.

The amplifiers have had almost daily use since 1993 and I've yet to hear anything for which I'd swap them. The original magazine articles talked about the quality of the output transformers (which their measurements backed up) and I've no reason to doubt them.
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  #9  
Old 22nd January 2009, 12:52 AM
Nakman Nakman is offline
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Default I dont believe it! Pink nail varnish maybe involved

My Beloved asks well 'why dont you paint the transformers with heat resistant pain until you get something sorted out?'

She is an artist so has that sort of approach.

I thought I'd just throw this in to shock you and show how standards are dropping around here!

I answered that althought there did appear to be lacquer on the transformer plates etc this didnt mean paint was viable or safe!

I tried to sound authoritative but thought I'd check! and maybe cause 'much girning in the marsh'.
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  #10  
Old 22nd January 2009, 09:03 PM
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Greg. Greg. is offline
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Default Re: 5-20 received yesterday and revived toady

To maitain good appearance I always spray the edges of the Tx lams with satin black Plasticoat prior to construction. It will easily tolerate the temperatures and stops the edges rusting with the passage of time. Your biggest issue is trying to find matching covers.
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