Retube Time.....Soldano SLO-100

[RockyStar]

Time to retube my SLO-100 soon. I am still kicking around ideas on what Power Amp tubes to use and if you have some great pre-amp tube ideas throw them in as well. I figured I would ask and get some opinions from other owners who have ventured down this path. What would you choose and why?

 

[Rick Lee]

Tough call. I have JJs power tubes in there now, but I have a new set of EHs I think I will put in there next. Preamp tubes are NOS GE or Motorolas and really made a huge difference over whatever was in there before. I don't play my SLO much, but ran it as a 50w with two power tubes for a while, then went back to all four at 100w. So they're unevenly worn and I'll have to retube it if I start gigging with it again soon. Color me subscribed.

 

[RockyStar]

I hear you. I am not sure if I want to go EL-34, or something else? So I am looking not only for brand but more so tube type.

 

[Rick Lee]

How can you put EL34s in an SLO? Change out the screen resistors?

 

[RockyStar]

How can you put EL34s in an SLO? Change out the screen resistors?

It can be modified to take different tubes. I am not sure I want to get into all of that if I can help it. I just want to try something different and see how it goes. I tried the 66's and didn't love them....didn't hate them either but may just go back to stock and say hell with it and just play it. I love the amp, just itching for a little change since i need to re-tube.

 

[godgrinder]

I like 7581A's. Did a comparison clip a while ago:
viewtopic.php?f=3&t=182128

 

[SpiderWars]

I like an RFT in V1, 5751 in V2, Shugaung (older ones) in V3-V4, Sovtek LPS or new Mullard in V5. The Shuguangs should have the square getters (the orig SLO pre tube), the newer ones with round getters are brighter/harsher. The reduction in gain from the 5751 lets me run the gain higher which reduces the effect of the bright cap which for me is a good thing. There's a dude on TGP selling RFT pres for decent price, let me know if you need contact.

I haven't rolled that many power tube types. I have a set of discontinued Shuguangs (called Red Box, Lord Valve has them, not expensive) in there and every time I try a different tube those Shuguangs win.

 

[Racerxrated]

I've tried them all, 6L6 and variants including KT66. Best to my ears were the Sovtek wafer bottom 5881s. Not tried 34s which would require modding. But there's a reason Mike puts those wafer bottoms in. Cheap, reliable and they sound great. Bias around 28ma and you're set. Pre tubes, I've played with lots of combos and the Chinese 8th gen sounded best, with a Jan AT7 in the pi spot. Had my last SLO last year, that's my experience.

 

[Chester Nimitz]

Ive heard good things about these ...

 

[SBlue]

I've tried them all, 6L6 and variants including KT66. Best to my ears were the Sovtek wafer bottom 5881s. Not tried 34s which would require modding. But there's a reason Mike puts those wafer bottoms in. Cheap, reliable and they sound great. Bias around 28ma and you're set. Pre tubes, I've played with lots of combos and the Chinese 8th gen sounded best, with a Jan AT7 in the pi spot. Had my last SLO last year, that's my experience.

This is what I've found too. Tried a few different 6L6/5881s, and ended up using what it came in from the factory for power tubes.
For preamp tubes, if you can get well tested new tubes, try a few different ones.
I've got chinese pres on all slots and I've been very happy with it.

 

[duesentrieb]

Ive heard good things about these ...

Max. plate and grid volts: 400V DC.

http://www.tubeampdoctor.com/images/Fil ... ng-Sol.pdf

 

[FourT6and2]

Just the regular stock Sovtek wafer bottom 5881s. All the power tubes are gonna sound the same for the most part in the SLO. Its power section is hi-fi and not meant to really break up at all. Unless you're running it on 8+, in which case you're deaf.

 

[SpiderWars]

Ive heard good things about these ...

Max. plate and grid volts: 400V DC.

http://www.tubeampdoctor.com/images/Fil ... ng-Sol.pdf

FWIW, the Sovtek 5881WXT is rated at 360v max plate, 270v max screens, and 23W max plate dissipation (per Duncans Amp pages). The Tung Sol 5881 is made by Sovtek so it's possible that it too is WAY tougher than that but I don't know. Tung Sols are generally bright and ime that's not the best for the SLO.

 

[SpiderWars]

Just the regular stock Sovtek wafer bottom 5881s. All the power tubes are gonna sound the same for the most part in the SLO. Its power section is hi-fi and not meant to really break up at all. Unless you're running it on 8+, in which case you're deaf.

If you have a Depth control (which imo the SLO either doesn't need or only needs a tiny bit) then the power tubes can make a bigger difference. Some tubes seem to have a more extended bass that makes the Depth control more pronounced. I tried one set of GT 6L6GC and the Depth control barely even worked.

 

[Jayy]

The only tubes I have used in the power section of my SLO are the Sovtek wafer bottoms that come from the factory and the Preferred Series 6L6GC from The Tube Store, which from my understanding are just a selected or special tube request set of Chinese Shuguang 6L6GC-BSTR. I have been very happy with both, but prefer the Preferred Series 6L6GCs a little more. There isn't a massive difference in the SLO using either one, but the Preferred Series 6L6s were just a little sweeter somehow to my ear. They have a little more solid low end or low mids or something.

 

[Rick Lee]

Just the regular stock Sovtek wafer bottom 5881s. All the power tubes are gonna sound the same for the most part in the SLO. Its power section is hi-fi and not meant to really break up at all. Unless you're running it on 8+, in which case you're deaf.

If you have a Depth control (which imo the SLO either doesn't need or only needs a tiny bit) then the power tubes can make a bigger difference. Some tubes seem to have a more extended bass that makes the Depth control more pronounced. I tried one set of GT 6L6GC and the Depth control barely even worked.

Mine does have a depth mod, which doesn't seem to do much with my JJs, which I had put in at the same time my tech did the depth mod. Which power tubes do you think would make the depth mod shine the most? Still Sovtek wafer bottoms? Any opinions on EH? They came in the package with my Dectone, but I've never installed them in any amp. Kinda wondering if they're worth putting in or eBaying off.

 

[RedPlated]

I have JJ 6L6's in power section. My factory depth mod is very noticeable and makes a significant difference in the sound. I don't think using JJ's has anything to do with its effect.

I have a NOS GE 12ax7 in V1. Best sounding tube out of probably 10-15 I tried. I have a Sovtek LPS in rest of slots and it sounds incredible. I rolled tubes for a long time in my SLO.

 

[SpiderWars]

Just the regular stock Sovtek wafer bottom 5881s. All the power tubes are gonna sound the same for the most part in the SLO. Its power section is hi-fi and not meant to really break up at all. Unless you're running it on 8+, in which case you're deaf.

If you have a Depth control (which imo the SLO either doesn't need or only needs a tiny bit) then the power tubes can make a bigger difference. Some tubes seem to have a more extended bass that makes the Depth control more pronounced. I tried one set of GT 6L6GC and the Depth control barely even worked.

Mine does have a depth mod, which doesn't seem to do much with my JJs, which I had put in at the same time my tech did the depth mod. Which power tubes do you think would make the depth mod shine the most? Still Sovtek wafer bottoms? Any opinions on EH? They came in the package with my Dectone, but I've never installed them in any amp. Kinda wondering if they're worth putting in or eBaying off.

I haven't tried the 5881s just a few 6L6. I bought the Red Box Shugs when I built the amp (I think it was 2008-ish) but only recently tried others and only JJ and an unknown origin GT.

TBH, based on what racerxrated/others said, prob best to just start with the Sovtek 5881. If nothing else you'll have the benchmark tone to work from and they're cheap.

 

[FourT6and2]

Just the regular stock Sovtek wafer bottom 5881s. All the power tubes are gonna sound the same for the most part in the SLO. Its power section is hi-fi and not meant to really break up at all. Unless you're running it on 8+, in which case you're deaf.

If you have a Depth control (which imo the SLO either doesn't need or only needs a tiny bit) then the power tubes can make a bigger difference. Some tubes seem to have a more extended bass that makes the Depth control more pronounced. I tried one set of GT 6L6GC and the Depth control barely even worked.

I'd be interested to know how the Depth control's effect in the SLO depends on the brand of power tubes used. Whereas in other amps that use the same exact depth control, they do not.

 

[psychodave]

I'd be curious how NOS Sylvania 6L6's would sound.