high gain tubes for the MP1

[El Chiguete]

Ok so its gotten in to my head lately that since I'm giving the final touches to my gear its time to think of tubes too. So I was looking at options and I think it might be down to these two:

- 7025 WA TAD http://www.tubeampdoctor.com/en/shop_TAD_Premium_Tubes_TAD_Pre_Amp_Tubes_SELECTED/7025_WA_TAD_HIGHGRADE_Premium_Selected_2192
- Mullard CV4004 http://www.thetubestore.com/Tubes/12AX7-ECC83-Tube-Types/Mullard-CV4004-12AX7

This TAD is not the one that has been talked before here, I believed the one you guys talked before was a lower gain version that you can compare in their catalog http://www.tubeampdoctor.com/pdf/TAD-Products_Info.pdf .

What do you guys think with this new TAD tube compared to the Mullard that some has tried?

Also thinking of the gain structure of the MP1, would you guys use the same one on both V1 and V2 or use different ones?

[rnolan]

Hey El, this is such a subjective area.... All I can advise is from the ones I've heard and you have MP1.  So boogies SPAX7s go REALLY well in MP1. Mike runs a Mullard short plate  in V1 and SPAX7 in V2 (IIRC) and this sounds nice and tight, good tones off his LP Classic. Based on my experience with Mullard long plates (in all of my 4 MP2's), they are the tube for me, and that's what I would start with. They add dimension and depth IMO, 3D if you like... Are they the tube for you ??? but I do know they won't disappoint you !!

[El Chiguete]

I was never clear if you used the long plates or the short plates version. Its interesting that they say this about the long plate versions that you use "Not really high gain at all, but a real good noise floor and a nice smooth tone that doesn't encourage ear fatigue the way some preamps can be." but for the short plates they say "The CV4004/12AX7 is a high gain, low noise valve with a short plate structure for reduced microphonics. Excellent for use in high gain Marshall pre-amplifier circuits where noise and microphonics can be a problem. Best for guitar amps."...

[rnolan]

Hey El, when I started using the long plates the short plates weren't around, they came out a bit later. The comparison I got to make was I put in a pair of SPAX7s because I could buy them at my local music store.  I used them at one rehearsal.  Then I put in the long plate Mullards and used them at the next rehearsal.  The Mullards were simply amazing, not that the SPAX7s were bad, just not as good as the Mullards.  They also have lots of gain and are not microphonic at high gain high volume, but this is in a MP2 which has lots more gain than the MP1. Mikes MP1 sounds great with the short plate and a SPAX7 so that's a combination I can recommend from direct experience.

I put a pair of LPs in my 2nd MP2 as it had EH tubes which were quite ordinary when I bought it.  My next 2 MP2s already had a new pair of LPs in them when I bought them, so all my MP2s have LPs which I'm quite happy about :)

[vansinn]

Been a long time since my MP-1 days; however, I find it's pretty much the same with all preamps. IMHO it's more about the tonal balance and aggression vs smoothness than about max gain.
The TAD's I find not really high gain, but nicely aggressive in the presence range, especially the RT001, which works well for me in pos #1 (on my MP-2) where it results in good clarity.
The JJ Gold Pin ones are high gainers, and do not really possess that good a definition in the presence range. I never could determine in which position they'd fit (IIRC, Peter use them in the MB-1 bass processor).
For pos #2, I really don't like aggressive ones, but prefer more rounded-off ones, and would suggest one of the long plates, though I use a NOS Phillips ECC83 with gain in the early/mid 90's.