NOS sylvania 6L6GC in my amp

[zodiac272]

ok, I just put 2 matched pairs of these in my HRG IIC+ which was recently worked on by Mike B. so i know my amp is perfect. I swapped out my mesa STR 440's for the sylvanias. everything is fine, but i feel when I switch off standby to start playing there is a bit more audible pop than when I had the STR 440's and switched the standby to on. Then it sounds great in the clean and lead channel. I'm guessing I should check to see if the bias is in the range it should be? about 35 ma or so? Can I do any major damage?
otherwise, the tubes sound really good, but I still don't have use of my right hand well enough yet that I can really play much like I could. I can say that the sylvanias slid very nicely into the sockets, to the point where it was almost erotic. haha.

I will say that it sounds really great (clean and lead) with my 1x12 open/1x12 thiele mesa cabs. I love how mark series sound better every little notch they crank louder.


scott

 

[topcat0399]

......... I can say that the sylvanias slid very nicely into the sockets, to the point where it was almost erotic. haha.
scott

dude

 

[stokes]

If you arent able to check the bias to be sure,you can look at the tubes while playing and make sure they are not "red-plating".This will tell you they are "safe",but not necessarily optimal.Being "safe" just means they arent biased too hot and wont damage anything.But since you payed a premium price for some very good tubes,it is wisest to have them biased to work/sound the best they can.

 

[gonzald1]

If you arent able to check the bias to be sure,you can look at the tubes while playing and make sure they are not "red-plating".This will tell you they are "safe",but not necessarily optimal.Being "safe" just means they arent biased too hot and wont damage anything.But since you payed a premium price for some very good tubes,it is wisest to have them biased to work/sound the best they can.

agree.

 

[zodiac272]

hey thanks for responding...

I paid 100 for the quad... not bad. when they red plate, they will look really bright, instead of a warm glow? maybe make noise? so far so good then...

Also, since i just swapped tubes, I noticed I had Mesa STR-440 yellow color in it. I'm 99.9% certain I had Grey color when I sent it to mesa for + upgrade, and cap job/cleaning. Mesa said nothing about changing the tubes... my grey ones were brand new... couple hours on them. you think they would put a new set, as a courtesy, without saying anything? Are they saying yellows sound best? or they just grab any set of STR-440's...

Also, the tubes had reading of 24 ma for a pair, and 31 ma for the other pair. thats on the colder end of things right?

thanks again

scott

 

[stokes]

I dont think Mesa would give you a free quad of tubes.I am sure you paid for them.Yes that is on the cold side.Dont know where the plate v's are sitting,but at 450 vdc your 6L6's could safely go to 45ma's and the 34's at the same volts could go to about 38ma's.That would be at the normal 70% that you would target for most amps.The thing with Mesa's tho,is that you get so much gain and overdrive from the preamp in the lead mode that when you get up near 70% in the power section your overdrive can tend to get kind of ratty if you get too high with your lead drive.But of course,its all subjective.I find the clean channel breaks up real nice when biased at or near the 70% current draw.In my own IIC+ I have NOS 7027A's biased up at 70%,but I use 5751's in key slots in the preamp to take some of the edge off.I mainly use the clean channel with this amp anyway.

 

[zodiac272]

Yeah, not much chance they would give tubes away, but they kept the ones (grey) that I sent with the amp. no charge on the bill for new tubes. So far so good. The pop after switching standby isn't recurring, and I'm thinking I may have hit a string or something the first time i switched from standby.

thanks again for the help!

scott

 

[stokes]

That "pop" is not tube related,it is just caps charging/discharging,it is normal.

 

[zodiac272]

ok nice, thanks!
scott

 

[topcat0399]

ok nice, thanks!
scott

glad you got it sorted.

now go fondle your preamp tubes....

 

[zodiac272]

now go fondle your preamp tubes....

man that is perverted... but judging by the bottom of your signature, can't say I'm shocked. lol j/k I do have a thing for chinese, but I think I'm going to fondle some eastern European tubes... maybe a mix

scott