Guitar Gear Forum

Still chomping at the bits to get my Laney GH100S home.

The GH100S can be set to run 6L6 power tubes. I've seen other amps that were 6l6 amps that had KT66's in 'em.

Can I run KT66's in the Laney GH100S on the 6L6 setting?

I'd think so. My Engl is 6L6 amp, but I use KT66's. I wouldn't think it would have made that much of a difference, but yeah. I was about to sell that amp until I did that.

you can, but the GH sounds better with 6L6s IMHO so save your $...

Soooooo.....would that mean I can run KT66s in my 5150 212 combo?

You have to be cautious with using KT66's in amps that aren't designed to take them as their screens are much more flimsy than those of EL34s/6L6GC types. The screen voltage in the GH100TI/S is pretty high for a KT66 (~460V) and it only uses 1k5 screen grid resistors so I see that combination as resulting in glowing screens. Increasing the screen grid resistors to 3k3 would be wise as would perhaps adding a resistor in parallel with the choke but then it would sag like a motherfucker and thats not really what the GH series is about. Why do you wan't to use KT66's anyway? If you're conservative with how loud you play it then they might not die immediately.

Zozobra wrote:You have to be cautious with using KT66's in amps that aren't designed to take them as their screens are much more flimsy than those of EL34s/6L6GC types. The screen voltage in the GH100TI/S is pretty high for a KT66 (~460V) and it only uses 1k5 screen grid resistors so I see that combination as resulting in glowing screens. Increasing the screen grid resistors to 3k3 would be wise as would perhaps adding a resistor in parallel with the choke but then it would sag like a motherfucker and thats not really what the GH series is about. Why do you wan't to use KT66's anyway? If you're conservative with how loud you play it then they might not die immediately.

Gotcha.

As for running the kt66's, a buddy of mine has a quad laying around that he didnt like, so I thought I'd try em if they worked. I'll roll the 34's for now, but eventually wanna go with 6l6's. There are very few amps I like an EL34 in. I like more of a "bigger" / rounder sound.

I didn't have a problem with the tubes redplating, it just didn't sounds as good as 6L6s. I think the GH series sounds best with 6L6's. I didn't like the EL34s either.

Yeah. It'll be awhile before I have the scratch for new tubes.

I have a trade worked up on a MXR 10 band EQ. It'll be used in the loop of the Laney. I always liked running an EQ in the loop of my old 8 knob AOR Pro Tube Lead (god damn, I miss that amp) . Im hoping that I can get some of a similar vibe I got with the pro tube, with the GH100S. I think the GH100S will be a bit easier to deal with. The AOR sounded killer, but was always a bitch to get dialed in right. She was a finicky beast. When she was dialed in right, WOW.

I cant wait to run the Laney side by side with one of my hermaphrodite Superbass bastards :evil:

Didja get the laney yet? Or still working on the trade?

phrophus wrote:Didja get the laney yet? Or still working on the trade?

I got it, but I owe a bit on the difference, so he put it in layaway for me. I'll have it homw in a couple of weeks. I woulda went ahead & paid him the diff, but this pay check is "bill week", so Im having him hold it for me. Just made my house payment, & my light bill is due, so 1st things 1st

100 watt wrote:

phrophus wrote:Didja get the laney yet? Or still working on the trade?

I got it, but I owe a bit on the difference, so he put it in layaway for me. I'll have it homw in a couple of weeks. I woulda went ahead & paid him the diff, but this pay check is "bill week", so Im having him hold it for me. Just made my house payment, & my light bill is due, so 1st things 1st

Gotcha. Completely understandable. You'd be a shitty person if you bought an amp instead of paying your lectric bill or mortgage.

KT66 tubes require more filament current than a 6L6GC....so you have to watch that your PT can handle that.


Another problem is that sometimes in fixed bias amps they just can't be biased down cool enough without modifying the amp.


I have a Fender Concert II that I've been trying to install KT66 tubes in and it's been a real headache.

I used to run KT77s in my GH50L with no issues, dunno about the KT66s.

GH Laneys sound best with 6L6's, though with the right speaker the KT77's are right up there...

Yeah. I may look into 77's at some point.

I may look into a lower gain pre-amp tube, as they say the GH100s's & GH100TI's can be a bit hissy. I used to run 12AT7's in V1 of stock MArshall 2203's to tame them a bit.

I'll be using it with a quad of Mesa MC90's , and my other cab, which has a mix of Eminence Delta 12B & Eminence Lynch Super V.

100 watt wrote:Yeah. I may look into 77's at some point.

I may look into a lower gain pre-amp tube, as they say the GH100s's & GH100TI's can be a bit hissy. I used to run 12AT7's in V1 of stock MArshall 2203's to tame them a bit.

I'll be using it with a quad of Mesa MC90's , and my other cab, which has a mix of Eminence Delta 12B & Eminence Lynch Super V.

I much prefer a long plate 12AX7 (ECC803S) over a 12AT7 for dropping the gain down a pinch.

100 watt wrote:I'll be using it with a quad of Mesa MC90's , .

When I had my Laney Protube, I ran it through MC90's that amp liked those speakers

flyingskull wrote:

100 watt wrote:I'll be using it with a quad of Mesa MC90's , .

When I had my Laney Protube, I ran it through MC90's that amp liked those speakers

Yeah. My AOR Pro Tube Lead 100 worked good with them. At the time, I had them in a SLM/Crate/Ampeg (not sure what it was) 4x12. Real plywood, but not the best construction

Add another vote for 6L6s. My VH100 sounded great with the stock 6L6s, when they wore out I went over to E34Ls for a change. While they, the E34Ls, sound better than EL34s, they don't compare to 6L6s. If I used my VH100 more, I'd switch back, but it is a spare amp really now.

You're going to love the your Laney!

Derek