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The Black Adder
11-07-2010, 15:24
Hello all.

I have a Raysonic CD 128 of which is an amazing bit of kit, if you have not heard one then try and do so, I am well impressed!

Being as curious as I am I was wondering if anyone could give me some information about doing a bit of rolling with the quartet of 6922 valves it currently has in place?

The stock valves are Electro Harmonix and after reading up on them a lot of people prefer Mullards.

So my questions are:-

Which Mullards would be best?
Are they the matched paired E88CC tubes?
Gold pins = better?
How much would 4 matched pairs be?
Where is the best place to buy them?

Hope someone can help
Many thanks
___
TBA

jandl100
12-07-2010, 07:22
Mullards? Yup, good. And tbh those EH will sound a bit sad and inadequate in comparison.

Don't necessarily restrict yourself to Mullards though, I'm having excellent results with some NOS Amperex - I preferred them in my Graaf amp to Mullard and Telefunken. Very much horses for courses with valves - which is best depends on the circuit you put them in. But I'd be pretty damn sure that they would all be a significant improvement on the EH. Def worth trying a few different types!

The Black Adder
12-07-2010, 07:45
Where is the best place to buy NOS matched valves like Mullards, Amperex etc Jerry?

Cheese

jandl100
12-07-2010, 07:49
Dunno - I usually get mine on eBay! :)

6922/ecc88/6DJ8 ... I'd loan you some but I don't have 4 of anything. Pairs of Mullard, Telefunken no problem./ But not quads.

Here's a reccie that will likely get me shot down in flames by the valve gurus here ... I'd strongly recommend you try some pcc88 valves - 7DJ8 instead of 6DJ8.

Even the cheapo pcc88 will often outperform quite exotic ecc88 valves ime, and I've not come across an application where they haven't worked fine as a drop-in replacement for an ecc88. And yes, I've tried quite a few.

Spectral Morn
12-07-2010, 07:55
Where is the best place to buy NOS matched valves like Mullards, Amperex etc Jerry?

Cheese


As an option you could ring Ian Large at Alium Audio, he has a pretty big selection of NOS and new production valves. Really nice guy too imho/e :)


Regards D S D L

The Black Adder
12-07-2010, 09:06
Cheers Neil.

I'll take a look. Does the type of Getter make a difference in experience?

Cheers

The Grand Wazoo
12-07-2010, 09:25
Don't get too hung up on finding matched pairs for small signal valves - especially dual triodes.

Marco
12-07-2010, 09:50
Where is the best place to buy NOS matched valves like Mullards, Amperex etc Jerry?

Cheese

Hi Joe,

IME, Watford valves are excellent in that respect with new valves. They also do it with NOS, but you need to phone up for that. Some others recently have also recommended Hot Rox:

http://www.hotroxuk.com/matched-valves-links-page-12ax7-6l6-909-0.html

Marco.

Barry
12-07-2010, 13:18
Dunno - I usually get mine on eBay! :)

6922/ecc88/6DJ8 ... I'd loan you some but I don't have 4 of anything. Pairs of Mullard, Telefunken no problem./ But not quads.

Here's a reccie that will likely get me shot down in flames by the valve gurus here ... I'd strongly recommend you try some pcc88 valves - 7DJ8 instead of 6DJ8.

Even the cheapo pcc88 will often outperform quite exotic ecc88 valves ime, and I've not come across an application where they haven't worked fine as a drop-in replacement for an ecc88. And yes, I've tried quite a few.

Not going to shoot you down Jerry, but I'd like to make a couple of points concerning the PCC88.

Electrically it is identical to the ECC88, save for the heater voltage which is 7V. The PCC88 was designed for TV use, where the valves use a constant current 300mA heater; the idea being that they were connected in series and directly connected across the 240V mains via a dropping resistor.

Using a PCC88 in place of an ECC88, means that the heater of the PCC88 will be running at 10% under voltage. This is on the limit of under running heaters, any less cathode 'poisoning' can occur.

Joe, I can recommend The Chelmer Valve Company for valves. They can supply specific makes and will match pairs for you. I have bought several valves from them, including Mullard E88CCs - they are just up the road from me!

Regards

The Black Adder
12-07-2010, 14:04
Hmm.. interersting stuff.

I'm a newbie to tubes so thanks all for the info.

Cheers Barry, I think I'll give them a ring. Cheers Neil. Do you know if type of Getter makes a difference? - Just curious.

Cheers
Joe

Barry
12-07-2010, 14:15
Hmm.. interersting stuff.

I'm a newbie to tubes so thanks all for the info.

Cheers Barry, I think I'll give them a ring. Cheers Neil. Do you know if type of Getter makes a difference? - Just curious.

Cheers
Joe

Being outside of the electrode structure, the style of the getter ought in principle not to make any difference. However I'm sure valve connoisseurs will tell you otherwise.

One other thing to bear in mind, the ECC88 and PCC88 were designed to be used as an RF amplifier. As such they use a frame grid, to reduce inter-electrode capacitance, and are thus prone to being microphonic. As far as I know the 6922 does not use a frame grid, though it is electrically similar to the ECC88.

Regards

The Black Adder
12-07-2010, 15:29
oh... I thought 6922 was the same as ECC88's just with a different reference.

Barry
12-07-2010, 17:33
oh... I thought 6922 was the same as ECC88's just with a different reference.

The 6922 is identical to the E88CC and the E88CC01. It is similar to the ECC88; it has a higher anode - cathode capacitance, however it is so similar to the 6922, that I wouldn't let that stop you trying them out.

Mullard E88CCs were part of their 'Special Quality' valve series. Built to higher standards and subject to more thorough quality control and testing. They are more rugged and proof against mechanical shock and vibration, and because of that, likely to be more reliable. The E88CC01s were selected E88CCs, usually reserved for military use.

If you want the best, go for the Siemens E88CCa, usually simply called the CCa. These were hand picked E88CCs, reserved for the German PTT. They are very expensive ~ £50 each - if you can find them!

Regards

The Black Adder
12-07-2010, 18:14
Righto Barry... Many thanks matey, I think I'll try some Mullards. Chelmer Valve company were very helpful btw.

Cheers

Barry
12-07-2010, 18:17
Righto Barry... Many thanks matey, I think I'll try some Mullards. Chelmer Valve company were very helpful btw.

Cheers

You're welcome Joe. May I ask how much CVC are asking for a matched pair of Mullard E88CCs?

Regards

The Black Adder
13-07-2010, 11:10
Hello Barry, just short of £200

Batty
13-07-2010, 11:18
I must try a pair in my Copland, at the moment I have the cheapest I could find (read I'm skint) when one of the originals popped

Ali Tait
13-07-2010, 11:21
Langrex have a good selection-

http://www.langrex.co.uk/sales.html

Also Hi-Fi Collective-

http://www.hificollective.co.uk/valves/b9a_pre-amp_valves.html

The Black Adder
13-07-2010, 14:14
Mike at Chelmer Valve has been tops. He's found me 2 pairs of NOS Mullard E88CC's that all match as a quad... Great service!

Barry
13-07-2010, 19:49
Hello Barry, just short of £200

Bloody hell! :eek: Was that for two or four valves?

Regards

The Black Adder
14-07-2010, 05:04
4 valves

Barry
14-07-2010, 08:25
Ah -that's more like it. I bought a matched pair of NOS Mullard E88CCs from CVC a few years ago, but I don't remember how much I paid.

Regards

The Black Adder
14-07-2010, 10:23
They didn't have many left so they said, should be here today. Not sure how long they would take to bed in, would you know?... I guess it would probably be a while but I'll keep this thread updated.

Ali Tait
14-07-2010, 11:48
Should take a few hours,it'll probably be quite obvious.These are getting expensive now,but they'll last you a lifetime.Don't forget to take them out if you ever sell the player!

selfaddict
03-11-2010, 18:15
How are you getting on with your 6922's?

Have you tried Russian 6N23P-EV ones? Cheap and plentiful on offer, on e-bay for example.