some Qs for tubes in HRDx

[whitewave]

I'm going to buy a used MIA Hot Rod, it's a very good deal but I've to change all the tubes.
I'm in Europe but not going to use TADs because they're much more expensive than Svetlana C for example.
Assuming that I'll use 6L6GC are the SED C the best I can buy at reasonable prices?

I have a probe for single tube and I'll buy a matched couple of power tubes. The "right" spot at 68mv is the reading for the couple or for the single tube? Should I set bias at 34mv on a tube?

As for preamp tubes I'm going to experiment some lower gain ones, I'll use mostly clean channel with good pedals and I like smooth and not harsh/bright crunches, any suggestions?

V1= advantages/disavantages in using lower gain pre tube
V2= same question
V3= PI - same question.

Thanks.

[Guitar_Mc]

V1 Lower gain tube lowers gain for both channels.
V2 Lower gain tube lowers gain for both channels with more of an effect on overdrive channel
V3 Changing tubes might have an equalization change, but is not as critical. It just splits the signal to send to the 2 power tubes.

I changed V2 to a 12ay7 and am happy with the results.

68mv is a multimeter reading for a test point on the pcb that is in reference to both power tubes in action. You can use that as a starting point and adjust to taste. Please read Justin's instructions at...

http://studentweb.eku.edu/justin_holton/bias.html

I put JJ 6L6 power tubes in. I'm happy with them. Some people put JJ 6V6 in. There is a lot to consider when doing this.

Be careful inside the amp, they can be dangerous.

[TELEPICKER]

Make sure you get a balaced tube for V3. A 12ax7 will keep the amp sounding bright and a 12at7 or ecc81 will give a darker more bluesy tone.

Pete

[whitewave]

ok, darker and bluesy tone is what I'm looking for.
What happens to distortion? Is it smoother or not?

Any suggestion for specific non-NOS tube will be appreciated.

I'm going to play the amp with a PRS CE-22 for blues to classic rock to some stoner, obviously with pedals.

Thanks.

[TELEPICKER]

By Distortion I assume you mean the Drive and More Drive channels.
These are inherantly terrible on the HRDLx. The good news is that it is genuine tube distortion and so reasonable quality tubes should provide significant improvement. The level of improvement will depend on the quality of the tubes you use. I personally have used NOS tubes sourced from Watford Valves in England. They were not all that expensive. (Around 32 Euros) You should use a 12AT7 equivalent in V2. I have a Mullard CV4024/ECC81 cryo treated. The Drive channel is much improved although I almost never use this channel. I have a really clean sound and use a Boss ME50 for effects.
Another thing you should do is to change the Master Volume pot for an Audio Taper (Log) pot. This will give you more control over the Drive/More Drive. Fender used a Linear pot here to make the amp sound loud at low settings. All volume pots should be Audio Taper.
Hope this helps.

Pete

[whitewave]

Yes, I know HRDx drive channel is terrible, infact I'm thinking at this amp as a single channel clean amp. I was forced to sell a Ceriatone plexi, I know what a good tube distortion is, I just can't live with the drive channel of HRDx.
But I need to go on the cheap range, so since I have some good pedals a Fender Hot Rod or a Traynor YCV seem reasonable choices.
I want to stay on a warm clean/crunch sound and add pedals, no more than that.

Yesterday I've found a good deal on a Traynor YCV40 WR with Celestion V30, quite the same price of the Hot Rod, the right speaker and no need to retube.
Unfortunately I can't try it because they're no more imported here in Italy and it's a private deal for a used amp far from me.
Fender HRDx can be easily modified, but I'm a bit concerned about cold solder points issues and plate load resistors, while the Traynor seems more reliable.

Thanks.

[dirtdog]

ok, darker and bluesy tone is what I'm looking for.
What happens to distortion? Is it smoother or not?

Any suggestion for specific non-NOS tube will be appreciated.

I'm going to play the amp with a PRS CE-22 for blues to classic rock to some stoner, obviously with pedals.

Thanks.

hey whitewave - I have just gone through what you are going through (with the Deville, not the Deluxe). Do some searches on this forum and you will find all sorts of wonderful information. Justin Holton's site and eurotubes.com have been particularly helpful resources.

FWIW, I put in GT 12AT7s in V1 and V2 and JJ 6V6s in the power slots biased at 42mV (for both) at the bias test point. I kept the stock Fender/GT 12AX7 in V3.

I found that the lower gain tubes in V1 and V2 defintely softened the harshness of the gain on the Drive/More Drive channels. The 6V6s and the 12AT7 in V1 gave me VERY desireable breakup on the clean channel - my picking dynamics come through much more blatantly now. I'm a blues/rock player and have found that with this setup I get much more useable tone than stock out of the box or with higher gain tubes in general. I use a Voodoo Lab SparkleDrive for boost/additional grit as required.

I'm looking to try other 12AT7s or 12AY7s in V1 and V2 just to see what they sound like.

I also owned and played the Traynor YCV40WR with the Celestion. I liked the sound, I liked the reliability but I wanted a bit more volume and a more organic, "Fendery" if you will, reverb. Hence the Deville. Now I've dropped the wattage down on the Deville using the 6V6s, but I still love the dark powerful 2x12 sounding coming out of the Deville over the 1x12 Traynor.

Good luck!

DD