Anybody use KT77s in an SV20?

1234_thumbwar

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I only have one pair of spare EL34s since the ones in my JCM 800 died a couple days ago.

I normally use EHX EL34s and they sound raucous and riley like a JMP should but I’m wondering how Gold Lion KT77s would sound if they’re even capable of being used safely with an SV20 since it’s cathode bias.

I love the way my SV20 sounds but I’ve never had a big bottle amp you can swap tubes with so easily and curiosity has me looking for opinions from those who have done KT77 or 6CA7 swaps in their SV20. Does it sound fatter for lack of a better word? More room for the lows? Also would I have to do anything to safely run KT77s? If it’s a real hassle I’ll stick with EL34s but curiosity has wanting to know.

I’d have also looked into 6550s but I’ve heard they’re a no-go for this amp. Not sure why but I’ll take any info I can get
 

Mitchell Pearrow

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I only have one pair of spare EL34s since the ones in my JCM 800 died a couple days ago.

I normally use EHX EL34s and they sound raucous and riley like a JMP should but I’m wondering how Gold Lion KT77s would sound if they’re even capable of being used safely with an SV20 since it’s cathode bias.

I love the way my SV20 sounds but I’ve never had a big bottle amp you can swap tubes with so easily and curiosity has me looking for opinions from those who have done KT77 or 6CA7 swaps in their SV20. Does it sound fatter for lack of a better word? More room for the lows? Also would I have to do anything to safely run KT77s? If it’s a real hassle I’ll stick with EL34s but curiosity has wanting to know.

I’d have also looked into 6550s but I’ve heard they’re a no-go for this amp. Not sure why but I’ll take any info I can get
:welcome:
To The Forum
All I can add is try them and see if you like the difference.

Mitch
 

1234_thumbwar

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:welcome:
To The Forum
All I can add is try them and see if you like the difference.

Mitch
I run KT88s in mine. Not a huge difference from el34s. I would imagine Kt77s would be even tougher t
I run KT88s in mine. Not a huge difference from el34s. I would imagine Kt77s would be even tougher to discern
You kind of make me want to stick with the EL34s but worse case scenario is I’ll stick them in my 800 and hope I hear a difference there. How do KT88s sound with it?
 

Kelia

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I only have one pair of spare EL34s since the ones in my JCM 800 died a couple days ago.

I normally use EHX EL34s and they sound raucous and riley like a JMP should but I’m wondering how Gold Lion KT77s would sound if they’re even capable of being used safely with an SV20 since it’s cathode bias.

I love the way my SV20 sounds but I’ve never had a big bottle amp you can swap tubes with so easily and curiosity has me looking for opinions from those who have done KT77 or 6CA7 swaps in their SV20. Does it sound fatter for lack of a better word? More room for the lows? Also would I have to do anything to safely run KT77s? If it’s a real hassle I’ll stick with EL34s but curiosity has wanting to know.

I’d have also looked into 6550s but I’ve heard they’re a no-go for this amp. Not sure why but I’ll take any info I can get
All I can say is that Gold Lions in my 2204 JMP really sound great ! My tech was really surprised when he heard them after a bias .
Welcome by the way !
 

Dogs of Doom

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I’m still trying to figure out how to reply to people if I even am doing this correctly but I appreciate the welcome
right now, we've had an unbelievable amount of fake accounts, scammers & spammers on the forum, so all new members are on probation/moderation to post. It's sad that it's come to this, but, I'm seeing it everywhere, not just music forums...

Just be patient & hang in there.
 

1234_thumbwar

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All I can say is that Gold Lions in my 2204 JMP really sound great ! My tech was really surprised when he heard them after a bias .
Welcome by the way !
I guess I’ll throw them in my 800 if they don’t sound much better in the SV20 but my 800 is that 2x12 combo so it might be a while before I do since I’ve got to take it to a tech and have it biased. Thing has to weigh at least 70 lbs
 

1234_thumbwar

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I put gold lion 66s in my 50 watt. They were OK but not night and day difference. Then one of them died spectacularly with a bang that woke the dead cats up. Also darn near made me crap myself. Luckily I hadn't had allbran for breakfast.
I don’t think I’d go for 66s until I have a proper JTM45 to put them in, was your 50 watt alright after that?
 

1234_thumbwar

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right now, we've had an unbelievable amount of fake accounts, scammers & spammers on the forum, so all new members are on probation/moderation to post. It's sad that it's come to this, but, I'm seeing it everywhere, not just music forums...

Just be patient & hang in there.
It’s all cool I’ve got no problem with it I just wasn’t sure if I was commenting to myself or replying to others for a bit
 

skiltrip

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I just bought a used DSL20hr and it's got JJ KT77s in it. All I know is it sounds fantastic, but no idea if it's any different from what was in there stock.
 

Maggot Brain

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I tried Gold Lion KT77s when I had my SV20. Also KT66 and different brands of EL34. I didn’t hear much difference. They all made the amp sound good. Maybe I have tin ears…
The KT77s are in my JCM900 now. Sounds good too.
So I take it the SV20 can handle KT66s?

I'm itching to pick one up and lust over the idea of shoving some kt66s in her....
 

1234_thumbwar

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So I take it the SV20 can handle KT66s?

I'm itching to pick one up and lust over the idea of shoving some kt66s in her....
I think there have been plenty of posts where people have done KT66 swaps on this sub but I don’t want to go and give you the go ahead as if I’m a tech or anything like that. All I know is there’s a lot of space in my combo and I’m sure it’s a similar scenario with the heads.

As far as I know the only tube that will fit that I haven’t seen people try are 6550s but I’m pretty sure I’ve seen a couple kt66 swaps here
 

Maggot Brain

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I think there have been plenty of posts where people have done KT66 swaps on this sub but I don’t want to go and give you the go ahead as if I’m a tech or anything like that. All I know is there’s a lot of space in my combo and I’m sure it’s a similar scenario with the heads.

As far as I know the only tube that will fit that I haven’t seen people try are 6550s but I’m pretty sure I’ve seen a couple kt66 swaps here
I've been away for a bit and a little out of the loop. Figured plenty or members have tried the kt66s but since this is a recent thread figured I'd ask.

I'm curious about the 6550s now as well. I used to own a 2204 with them and LOVED how percussive that amp was. Would be cool if someone from Marshall popped on the forum and explained in more detail what is or isn't usable in the studio amps.
 

Kinkless Tetrode

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I put KT66s in my mini Jubilee a few times. No problems at all. And I did notice a difference. Clearer more sparklely cleans and a less modern, or less saturated, overdrive. But slightly less loudness per volume setting. Not an SV but essentially the same or very similar power amp. I normally run fat bottle EH6CA7s in it,
 

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