New Tubes Advice

[trader144]

http://www.tgpwebzine.com/?page_id=83

Good article on tubes including a Mullard alternative

[trader144]

When I look at the schematics there is a definate difference in the size of the negative resistor between V1 and V2. This means they are biased differently.

Based on the very small V2 resistor I would say it is probably near center biased. Based on V1 having a larger resistor than V2 I would say it is not center biased.

So consistent with the MP-1 user manual, V1 and V2 have different purposes as in V1 is for more distortion than V2. So different tube purposes..

Notwithstanding the above, most of the color comes from
V1 since that is the first place the sound is being duplicated/amplified.

David

[MarshallJMP]

trader,keep in mind that the kathode resistor of V1 is not connected to ground but to the -15V,so that's why the reistance is higher!

[rnolan]

And also different EQ is applied in the tube circuits depending on voice setting.

[trader144]

Rnolan can u explain more?

[rnolan]

Rnolan can u explain more?

My understanding, and MJMP knows this better than me BTW, is that part of the choice of different voices (MP1 - SS,Cln T. Dist Tube) or (MP2 10 tube voices) etc. changes  things in the tube/(and SS MP1) circuits. Some of the change is eq, e.g. the MP1 Dist Tube has mid boost (MJMP has posted about this elsewhere here). My understanding is that this eq is in the V1 and V2 circuits (apart from overall eq).

[j4q0]

Took me a while but managed to read all the 12 pages, lots of interesting comments and questions.
So far mos of the preamp tube talk if for a stock MP1 aside from some mention about using long plates on a 3TM (which is the one I have)
I have been using a couple of Baldwin long plate tubes with good results but decided to change them for a mix of Boogies SPAX7A and Russian short plates.

I try to ride the volume of my guitar to play with different colors of overdrive and go to a quasi-clean tone but as MarshallJMP mentioned to me some time ago the 3TM has just too much gain to clean up nicely riding the guitar volume.

Though I like the way the 3TM sounds and has very low noise these tubes are old and I'm considering getting new ones, any other advise besides the Sovtek LPS long plates and the JJ to get a tight punchy high gain tone with enough bite but not thin sounding?

I like the description of Rnolan and the 3d of the Mullard, would this be a good idea for what I'm looking for? I like articulation and like that tracking of your every move like I've read this tube provides.

[rnolan]

Hey j4q0, Now I've heard a Mullard short plate (in MP1 V1 with Boogie STR/SPA in V2), the Mullards open up your sound and are very articulate and will suit volume riding but there's so much gain in 3TM as MJMP says. The Mullard long plates have more depth (but that's in my MP2), I found the 1 short plate in MP1 went the right direction. But as I run 2 long plates and love it, I wanted more  >:D . Theoretically the short plates should be less microphonic than the long plates, maybe at super high gain ?? but I haven't noticed. So an approach might be grab a few Mullard long plates and/or short plates, and try adding them one at a time from V1, V2, V3. You may find just one in V1 works for how you want it to sound ? The boogies are nice tubes , great feedback mmm >:D best I've heard BTW but a bit 2D, tight, not expansive. But the Mullard short plate in MP1 V1 with Boogie STR/SPA in V2 makes quite a difference. One comment MikeB made after he put them in was he had to be more articulate in his playing (as they track everything so well (good and less intended LOL)).
These are high gain tubes, but the articulation shines through even with copious distortion.

[El Chiguete]

Can't wait to see what Marshall says of the Mullards after he tests them!

Have,'t got the time yet.I need 48 hour days 

No time for testing them still?

[trader144]

For me after spending some time with them the Mullards were very 3D but I am leaning back to the original MP-1 tubes. The original MP-1 tubes have better note separation although the distortion is more digital sounding and there is more useable distortion range.

The Mullards have more of a classic overdrive sound but I think I have to give up note separation which is not a tradeoff I can accept.

[rnolan]

Maybe do a hybrid of one Mullard and one Boogie STR/JJ, works quiet nicely in MikeBs MP1 (V1 Mullard short plate/ V2 Boogie STR/JJ). I agree though the original tubes were very good, hard to get these days though. And I do find the Mullard long plates an improvement, but that's in MP2.

[rnolan]

Based on input from SC, it seems the closest modern tube to the original Chinese bottles are the TADs, so worth a try if you want the original stock sound, (which is awesome  )

[Dante]

IIRC, I have a TAD in one position and something else in the second position of my MP-1 Classic. I can't remember the details, but the TAD is great for clean sounds with lots of headroom. The other tube (whatever it is) is more for saturated gains.

I'd have to take the Classic out of the rack to figure it out, but it's marked on the top of the unit, so I don't have to take it apart to find out.

[trader144]

Go with a dual amp setup: an original MP-1 thru one amp and a mullard Mp-1 through another amp.

The original mp-1 will retain your note separation and the second mp-1 will add in the mullard sound

[dmax]

I see this is kind of an old thread but here's my 2 cents.

I put TAD's (Tube Amp Doctor) in my ADA MP-1. They work fine for me and I like them. I put the 7025/E83CC (RT030) in V1 and the 12AX7A-C (RT001) in V2.  I tried the 7025 WA (RT080) but it had more gain than the other two and it noticeably increased the noise level in the distortion voice (which is not normally noticeable).

There are probably some other combinations that would work well too.  The TAD and Humbucker Music websites have good descriptions of all the tubes.