Retubing Dual Recto Preamp

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Undeadpaladin

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Hey guys quick question, i know its pretty much subjective but i want to retube the preamp of my Dual Recto. I changed the stock V1 to a Tung Sol reissue only, seemed to sound a bit better than the stock one.

Anyway i'm running with a pair of El34's in my amp. I keep the effects loop off, so i know one position i can skip(I forget which V position is the loop). I play mostly very clean to crunchy classic rock sound(think ac/dc but more gain). I stay off the modern channel and mostly stick to raw with a tubescreamer in front. So i don't need gobs of gain or anything.

What preamp tubes do you think would sound the most sparkly clean(prolly my first priority) for the first channel. In addition which have that more vintage crunch and smoothness, not the typical recto buzzy high end.

Thanks for any feedback!
 
Thanks for the help!

What is the V5 position for exactly?

V1 is the most important and affects the tone the most correct?
 
V5 is your phase inverter/poweramp driver tube. It is best to have a balanced tube in this possiton. It's been my experience, w/ adj. bias amps anyways, that a balanced tube in this possition make the bias alot easier and more stable: ie an unbalanced tube and I watchd the bias meter jump around and never settle on a constant reading.
 
Thanks, any more feedback? Wanna keep the cleans as mentioned, but get rid of fuzzy and some of the harsh sound when the gain is turned up. Less of a cutting high and more smooth sounding.


While i'm at it, any suggestions for a power tube section? I tried straight El34's, wasn't crazy about them. I was looking at retubing with just a 6l6 variety. As said before, something very clean... don't need alot of low end, but very smooth sounding.

Thanks.
 
Shredd, you seem to be quite knowledgeable concerning the pre tubes and it was upon reading your posts that I purchased an NOS RFT to start with. It's labeled "Tesla". I have a 2002 Dual Rec 3 channel and it went down about six months ago. Burned spot on the main circuit board. I bought a Mercury OT for it and Mercury choke but until I find out if I need to pick up a new board I'm in wait mode. I like your choice of tubes but I play a heavier rock/metal style music and don't want to tame the DR too much. What would be your best suggestion to finish out the pre tubes. Looking for strong low end, strong low mids, and a smooth high end but very adjustable (prob what sold me on the RFT). Thanks!
 
Awesome Shredd! Dude you're right on. I had the Mullard 12Ax7 next on the agenda for V2. Expensive though. 129 I think at Tube depot. I was thinking what you suggested a long plate for V3. It's at this point that I need to attempt to open the amp up a bit and try to keep it aggressive. I may shy away from the AT7's. Also the Mercury mods may change this tube choice also. Until I find out about the circuit board I'm stuck though. Got a bad feeling the repairs to get it back to stock (ship to Mesa) are gonna be necessary b4 I can even advance to the next step.Not to mention costly! It should give me a little more time to get all of the tubes. Thanks Shredd! :D
 
Shredd what kind of mask is that your wearing?


Just kidding man, thanks for all the tube advice, I really like your explanations, you should be a lawyer.
 
So I just got off the phone with Tube Depot...




They suggested Sovtek 12ax7lps preamp tubes in all 5 spots.

Thoughts?

I asked about Mullard and RCA tubes, they said as far as "best value" I would be happy with the sovtek long plates. He said the Mullards are better, but not worth the price.


As far as Poweramp tubes I figured I would see what his suggestion was since I had him on the phone.

He suggested Sovtek 6L6 wts+ tubes in all 4. He said again they are the "best value" and are not far off from the more expensive and slightly better sounding high end tubes.

He said the best, in their opinion, for power amp was SED 6L6.


Any thoughts on this. I have heard great things about the mullards, and rca tubes.


Keep in mind we were talking about a tight metal tone with little noise. (unearth, etc..)
 
Shredd,
Ended up shipping my amp back to Mesa to get that burnt spot on the circuit board repaired. They may end up replacing the whole board and the tubes. I was running an integrated quad of 34's and 6L6's-all JJ's. Also all high gain JJ AX7's. I have here the new Mercury Mag Tranny and choke and the RFT AX7 for V1. I'm still hoping to go NOS Mullard for V2 and GE/JAN long plate for V3. It is from my understanding and I'll know more about this as time goes, that the burn was caused by the switching jacks in the rear of the DR while I was attempting to set up Voodoo GC and GCX units and not from the Integrated Quad of tubes.
0628081955.jpg
 
When you get that thing fired up again it's gonna feel like Christmas Day.

That explains the MMOT red end bells. Now if only I could order a green Power Tranny! HA! In December I may even apply for an internship at Santa's Workshop! :lol: I'm looking forward to it. I emailed Jerry at FJA mods and asked if he would do this work for me cause I am a bit interested in the DR FJA mod. I've always said and will say again, "If you're gonna do it, do it right or not at all."
Off subject here, Undead I owe you an apology. The last three or four posts of mine I never even asked how your amp and tube selection came along and this was originally your post. So how did it turn out?
 

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