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diviy
07-10-2016, 22:09
found this vave preamp on ebay anyone heard one or recommend a valve pre cheap as possible
http://www.ebay.co.uk/itm/282183028724?_trksid=p2060353.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT

struth
07-10-2016, 22:27
Dont see an earth wire coming out of the mains socket, so worth checking that if you did get it.

walpurgis
07-10-2016, 22:34
I've had plenty of Chinese electronics and you tend to get what you pay for. It may sound just fine and be OK with UK mains, but the finish and standard of construction will be what I call 'hasty'. At the price though, if it does what you want, why not?

Not all far eastern Hi-Fi is dubious. There are some very well made products.

struth
07-10-2016, 22:38
indeed.. not saying it isnt :) but see stuff from there that isnt earthed

diviy
07-10-2016, 22:51
ok cheers anyone got a recommendation for a good VFM valve pre max £200.00 dont mind second hand

walpurgis
07-10-2016, 23:20
What power amp are you planning to use with it Gerald? There may be good alternatives to a valve pre-amp. £200 is unlikely to buy you anything sensible with valves.

I like valve gear, but haven't used a valve pre-amp for a few years, even though I have a rather nice one on the shelf.

diviy
07-10-2016, 23:35
I have two Arcam alpha P8 amps had a really good price for them to be recapped and upgraded. I was advised to look for a valve pre as my Arcam A65 is a integrated with pre out`s but was advised to get a dedicated pre amp to help open up the sound. If I am not going to get much by spending only £200.00 on a valve pre is there any good VFM ss amps I could look up .I am medically retired so have to do things on a budget that is why I do not mind second hand.

Firebottle
08-10-2016, 06:34
Hi Gerald, that pre-amp looks good to me, but with two caveats.

One , it definitely needs an earth connection to the chassis, two I would fit a small bucking transformer to give safe operation at 240V mains.

There is a good report from one user on the web. Do you have any electronic skills? The chassis is open enough for easy modification of circuit or components.

Cheers.

JohnJo
08-10-2016, 08:02
If you don't need a phono stage a passive pre might do you.

Or here's the obvious choice to go with your power amps, an Arcam Alpha 9 preamp which they should be able to post.

https://www.gumtree.com/p/amplifiers/cambridge-audio-pre-amp/1191978365

petrat
08-10-2016, 08:23
To start, maybe just look for the matching Arcam pre secondhand? My only experience of trying to pair an Arcam amp with another make, didn't work too well ... humming, as the grounding approach on the arcam was a bit odd, and wouldn't work well when connected to non-arcam stuff. It may have been a one-off problem, but suggest you try to get a trial with whatever you buy, before committing?

Maybe put a 'wanted ad' on this forum, explaining the situation? There are some right hoarders who have all sorts stashed away, so you might be surprised.

walpurgis
08-10-2016, 09:06
If you don't need a phono stage a passive pre might do you.

Or here's the obvious choice to go with your power amps, an Arcam Alpha 9 preamp which they should be able to post.

https://www.gumtree.com/p/amplifiers/cambridge-audio-pre-amp/1191978365

Good suggestion! :thumbsup:

Macca
08-10-2016, 09:27
You might get a Croft Micro Basic second-hand at around £200. Will be better than the cheapo chi-fi, safer too. No idea if it would work well with the Arcam though. I tried mine with a few power amps, it didn't like a Behringer A500, otherwise it was fine. Sounds a bit 'valvey' but I'm assuming that is what you want.

Firebottle
08-10-2016, 09:34
I have studied the circuit of this valve preamp and with a re-wire using the SAME components it could be turned into something quite good, with only one coupling capacitor in the signal line.

Even better to start with the kit and wire it differently from the start. I notice the kit doesn't come with a step by step guide, just a circuit.
Would anyone who fancied building their own preamp from the kit be interested in a step by step guide to build to my new circuit?

Marco
08-10-2016, 14:55
Unfortunately, Gerald, good active preamps, valve or otherwise, but especially valve, don't come cheap. That's why the advice here of going for a passive instead is good.

My advice, based on considerable experience in this area, is that if you're thinking about an off-the-shelf commercially produced item, don't even think of going for a valve preamp with less than £700-800 to spend, and even that is an absolute minimum.

However, if you're able to go the DIY route, then the story changes considerably.

Marco.

Arkless Electronics
08-10-2016, 15:07
.... and there is a DIY valve pre amp design by my good self here on AOS in "The Drawing Board" section which sounds superb and can be built for about £200;)

Marco
08-10-2016, 15:16
Now that would be one to go for! :cool:

Marco.

Sherwood
08-10-2016, 15:20
Gerald,

I know it is more than you wish to spend but I have a Croft Super Micro that has been in storage for many years whilst I was working overseas. In excellent condition, with new regulator valve fitted recently. Other forum members will attest to the quality of this pre-amp and especially its phono section. Will sell for 300 quid plus postage.

Alternatively, you may be interested in my Antique Sound Labs integrated valve amp, although this does not have a phono pre-amp just line in. That is on sale for 400 with brand new valve set (plus postage).

Geoff

diviy
08-10-2016, 22:43
Thanks Geoff way out of my budget. Ff I have to go ss what about a 70s jap preamp any recommendations

danilo
09-10-2016, 02:28
Having been erm 'naive' years ago and believing the Stereo-Pile bullshit recomendations.
I spent large ish (for me ) and bought a pair of Arcams. Inty and it's matching Power unit
Mo' is better.. certainly so, according to their brochure babbles.
Turned out to be crap sounds when all was said and done.
The Twit Arcam designers had No clue as to their craft.
Rendering amps with irfp240 Output devices as Piss Poor sounding. That's a singular accomplishment.

Fixating on a Pre is perhaps misguided.
That's Not going to help when saddled with Arcams.
Replace the Amps with 'anything' and Smile.
Then If you still feel the need (inevitable :) A Simple Stoopid 10 K pot may surprise. Also a very inexpensive experiment.

Sherwood
09-10-2016, 09:10
Gerald,

another option is to bypass preamp altogether. My Cambridge CXN music streamer has option of being used as a digital preamp. It performs very well and I am guessing there are other streamers at a lower price that have this facility.

Personally, I would avoid cheap valve pre-amps and go passive or ss.

Geoff

paulf-2007
16-10-2016, 09:03
Dont see an earth wire coming out of the mains socket, so worth checking that if you did get it.
Just come across this thread and you are right Grant about the earth. I bought a 6P3P amp by the same seller I think, from eBay. It came with a Chinese power lead, iec one end and Chinese plug the other with an adaptor for a UK plug. The adaptor had no earth, neither did the amp have an earth connected to the iec socket so connected an earth to the chassis and used a UK power lead. I also switched it on with just the rectifier to check the magic smoke was properly contained. I used the amp in my office system for some time before it developed a rustling sound that turned to be a loose connection which John Howes fixed while I was working in his museum. He also changed some of the caps for Russian paper in oil and put a resistor on the mains transformer as it is 220v. He rewire do it to triode mode and it sounded very nice into the voxativ ampeggio dues. John said he couldn't buy the parts for what I paid for the complete amp.

Dauntless
25-10-2016, 21:01
Just to add my 2p worth to this thread before it pops into virtual reality. I have a couple of these Douk valve pres one for £48 and one for £28 which you buy as a kit and assemble yourself a bit like a chinese Ikea! The P3 ( the expensive one ) is fitted with a transformer and a rectifier valve. When I put it together it had a Chinese mains lead and plugs and was clearly 220v. I sent it to David Lane in Gravesend and he sorted it out for me using power resistors to level things out for our Uk mains and earthing the unit and changing plugs leads. http://www.valveamprepair.co.uk/
Sounds damn good now. The £28 unit is fitted with a switch mode power supply so works without any fettling. My friend bought one and compared it to his Vincent Valve pre and he cannot tell the difference between the two units. So yes I agree the Douk pre will probably be very good with a little fettling as Firebottle says.