6L6 very early 1970's silverface super reverb amp tubes

[boxocrap]

ok here's the question..like the title says i have a early 70's fender silverface s.r. amp and another 6L6 ( mid 80's amp)
I've been wondering if i can use el84's or 6v6's in it ( or them)with an adapter set i bought that plugs into the standard socket for the power tubes..the adapter is the same basic idea as a yellow jacket and was made in the US or japan ( it's kinda old) 6v6's in place of 6L6..but the plate voltage i looked up shows a difference between the el's and 6v6 but not a radical difference..so if i use the 6v6 ( with re-biasing) can i do this or am i looking at some sort of meltdown..i expect the 6v6 won't last as long but what else could potentially happen ?
i am not an x-spurt ( joke) in this stuff so i thought i would ask here to the folks who would probably know..thx in advance for any and all real advice.

 

[schmee]

If you know how to bias you could try 6V6's easily. The output will be a match for 4 ohms with 6V6's, but that's close enough for the speaker load. You may want to run JJ 6V6's depending on how high the amp's power tube plate voltage is. If you over stress a 6V6 it COULD take out the output tranny. Just saying it's possible.

I have tried a couple times to use EL84's using adaptor's in 6V6 style amps with little success. It sounded like garbage, obviously needing other changes.
If you are trying to 'tame the beast' I would try the 6V6's, maybe a lower voltage rectifier tube, 5V4 or even a 5R4 or 5Y3. These amps from the Deluxe on up are very much the same inside except for minor changes.

 

[boxocrap]

If you know how to bias you could try 6V6's easily. The output will be a match for 4 ohms with 6V6's, but that's close enough for the speaker load. You may want to run JJ 6V6's depending on how high the amp's power tube plate voltage is. If you over stress a 6V6 it COULD take out the output tranny. Just saying it's possible.

I have tried a couple times to use EL84's using adaptor's in 6V6 style amps with little success. It sounded like garbage, obviously needing other changes.
If you are trying to 'tame the beast' I would try the 6V6's, maybe a lower voltage rectifier tube, 5V4 or even a 5R4 or 5Y3. These amps from the Deluxe on up are very much the same inside except for minor changes.

thx 4 the reply..my super is rated for a 2 ohm output to the speakers..i am currently running it at 4 ohm with no detectable issues..( i simply disconnected two of the 8 ohm speakers)..it sounds ok..but wanted to try some other options like the el84's and 6v6..voltage is not that far off between the two tubes..but you raise a good point regarding the output tranny..it is an original and maybe? a little tired after all these years..i just want to see if there is any significant tonal change..and to see if i can turn it up for more power tube distortion at a lower level and yes i can bias..the 6v6 are legit nos rca black bottles from the 50's or therebouts and tested out at around 96%and 94% they are very closely matched

 

[schmee]

thx 4 the reply..my super is rated for a 2 ohm output to the speakers..i am currently running it at 4 ohm with no detectable issues..( i simply disconnected two of the 8 ohm speakers)..it sounds ok..but wanted to try some other options like the el84's and 6v6..voltage is not that far off between the two tubes..but you raise a good point regarding the output tranny..it is an original and maybe? a little tired after all these years..i just want to see if there is any significant tonal change..and to see if i can turn it up for more power tube distortion at a lower level and yes i can bias..the 6v6 are legit nos rca black bottles from the 50's or therebouts and tested out at around 96%and 94% they are very closely matched

Cool. Yeah it was RCA Blackbottles took out my output tranny on my BFDR. "FLash...zzzz... smoke" It runs 460volts which is much higher than the schematic indicates. Back then a new set of Electro Harmonic 6V6's wold last 3 months gigging with that amp. They just couldn't handle the voltage. The JJ's are bulletproof. That's a very robust OT in your Super so I wouldn't worry much about 2 vs 4 ohms and 6V6's.

The other option is to go to a more saggy rectifier like a 5R4 or 5V4 or... Then install 6L6WGB small bottle's (5881), they are lower wattage tubes. They are not expensive either. SYlvanias are great. And see if it gets you more in the zone without changing much.

 

[boxocrap]

thx for the reply..ok..i currently have a 5au in there for the rectifier and have at one point when i was doing cross country gigs a couple of 5881 long bottles..they lasted a long time and would stand up to high constant volumes but..i found with the long bottles..they stayed very clean almost to the max..so i would have to use my old mxr overdrive pedal..and put up with the noise with the strat singles..i did look at a chart for 6v6 not the rca ones..and it said 400v..where the el84 were about 40v less..so i thought ok maybe i can rebias for the el84's..then i got to thinking..well..i do have those adapters (basically yellow jackets for el84's..so because the el's and the 6v6 are fairly close ( according to the chart i saw..the adapters would be the way but..like you mentioned..i don't want to hurt this old workhorse as i use it in the studio now exclusively.so..if i put the rca 6v6 in the adapters and tried that..am i running a significant risk here? the super has been a great amp for me since i was about 19..when the only amps that could overdrive decently were very loud 50 watt marshals with their 4 12"speaker cabs..there wern't any amps back then that were around that had a master volume and distortion pedals were few and far between and sounded like total crap ( ya it was a long time ago) i wanted to be able to overdrive my super and always have wanted to..so here i am many years later thinking well...maybe if i do this with the 6v6's..but..you have given me pause to reconsider the jj's..as i understand it they are basically 6L6's in 6v6 form..able to tolerate higher voltages..but don't really sound the same as other 6v6's i don't really know that it's what i've seen online basically hearsay..your suggestion for a saggier rectifier say the 5v4 sounds quite plausible then short bottle 5881's.have you used any of these suggestions yourself? in your bf?..or do you still have it?..i will try out the 5v4 idea with small bottle 6l6 sylvanias i have..another matched set..thx again for the reply and..your ideas on this

 

[JustABluesGuy]

If I am understanding your goal correctly it’s to be able to get power amp breakup at less than stadium filling levels?

I’m assuming there is a reason using a good attenuator won’t work for you? I’m just curious why that isn’t your goto, especially since it could be used with any other amp, and you won’t have to modify a valuable vintage amp?

 

[NTC]

It is still going to be loud with 6V6's. Also, a 5Y3 rectifier is rather low rated for the amount of circuits in the amp, so that may not be a good idea. If you really want to try the 6V6's, get a 5R4 or a 5V4 Rectifier.

This sounds like a job for a Deluxe Reverb. Or a Vibrolux Reverb.

 

[Nicko_Lps]

ok here's the question..like the title says i have a early 70's fender silverface s.r. amp and another 6L6 ( mid 80's amp)
I've been wondering if i can use el84's or 6v6's in it ( or them)with an adapter set i bought that plugs into the standard socket for the power tubes..the adapter is the same basic idea as a yellow jacket and was made in the US or japan ( it's kinda old) 6v6's in place of 6L6..but the plate voltage i looked up shows a difference between the el's and 6v6 but not a radical difference..so if i use the 6v6 ( with re-biasing) can i do this or am i looking at some sort of meltdown..i expect the 6v6 won't last as long but what else could potentially happen ?
i am not an x-spurt ( joke) in this stuff so i thought i would ask here to the folks who would probably know..thx in advance for any and all real advice.

I have an EL84 converter set by TAD not yellowjacket and its in triode mode which means around 7-9 watts according to TAD. Its still lethally loud inside a room, if you wanna go really down on volume you better leave the tubes as they are and buy a Bugera PS-1 for example (it must be double your amp's output)

The 6V6 will fry inside a super reverb, you can only use JJ-6V6S which can withstand higher plate voltages. I have a set and i honestly do not like how they sound. Its more like...a small bottle 6L6, not a 6V6 and you will have to re-bias each time you swap from 6L6 to 6V6S.
Running EL34's(you need a modification to run them) and swapping to 6V6S my amp(dont know about yours) does not need a re-bias.

I would stick with 6L6 and buy a power soak!!

 

[boxocrap]

I have an EL84 converter set by TAD not yellowjacket and its in triode mode which means around 7-9 watts according to TAD. Its still lethally loud inside a room, if you wanna go really down on volume you better leave the tubes as they are and buy a Bugera PS-1 for example (it must be double your amp's output)

The 6V6 will fry inside a super reverb, you can only use JJ-6V6S which can withstand higher plate voltages. I have a set and i honestly do not like how they sound. Its more like...a small bottle 6L6, not a 6V6 and you will have to re-bias each time you swap from 6L6 to 6V6S.
Running EL34's(you need a modification to run them) and swapping to 6V6S my amp(dont know about yours) does not need a re-bias.

I would stick with 6L6 and buy a power soak!!

thx for your reply..i've got a "power soak" although they don't call it that..doesn't quite do what i want and won't handle a 2 or 4 ohm load..0nly 8-16..i agree about 6v6 ..i would have to rewire the amp too much for my liking..i'm kinda looking for something that's along the lines of an older deluxe reverb type sound maybe 20 watts though max..so maybe at some point i could get one..seems to be a safe way to go without destroying anything i already have..i do have another head that was originally designed to take 6v6..and had it modded to go from the stock 20 watt studio model to 50 watts for stage..i had a switch installed to change it from 6L6 to 6v6 and was informed it would work ok..the caveat being that 6v6 would not last as long but no damage to the amp would happen...but it does not have quite the sound i was looking for even when it's on the cleanest setting about 5% distortion...i do have one more option..on my other amp i had it wired to shut off the preamp section and use an input that allows for an outboard preamp to be inserted in it's place..i also had my super modded decades ago that has an output from the preamp section with a level control on it..i suppose i could use that take it from the super pre to the other amps power section and get the 6v6 thing happening that way..not ideal but..better than destroying the amps entirely..ya i will try that option 1st..seems the safest way at the moment..i should of thought of that as the 1st option..

 

[schmee]

thx for the reply..ok..i currently have a 5au in there for the rectifier and have at one point when i was doing cross country gigs a couple of 5881 long bottles..they lasted a long time and would stand up to high constant volumes but..i found with the long bottles..they stayed very clean almost to the max..so i would have to use my old mxr overdrive pedal..and put up with the noise with the strat singles..i did look at a chart for 6v6 not the rca ones..and it said 400v..where the el84 were about 40v less..so i thought ok maybe i can rebias for the el84's..then i got to thinking..well..i do have those adapters (basically yellow jackets for el84's..so because the el's and the 6v6 are fairly close ( according to the chart i saw..the adapters would be the way but..like you mentioned..i don't want to hurt this old workhorse as i use it in the studio now exclusively.so..if i put the rca 6v6 in the adapters and tried that..am i running a significant risk here? the super has been a great amp for me since i was about 19..when the only amps that could overdrive decently were very loud 50 watt marshals with their 4 12"speaker cabs..there wern't any amps back then that were around that had a master volume and distortion pedals were few and far between and sounded like total crap ( ya it was a long time ago) i wanted to be able to overdrive my super and always have wanted to..so here i am many years later thinking well...maybe if i do this with the 6v6's..but..you have given me pause to reconsider the jj's..as i understand it they are basically 6L6's in 6v6 form..able to tolerate higher voltages..but don't really sound the same as other 6v6's i don't really know that it's what i've seen online basically hearsay..your suggestion for a saggier rectifier say the 5v4 sounds quite plausible then short bottle 5881's.have you used any of these suggestions yourself? in your bf?..or do you still have it?..i will try out the 5v4 idea with small bottle 6l6 sylvanias i have..another matched set..thx again for the reply and..your ideas on this

I have used the various rectifiers in many BF amps. Mostly my Deluxe's, and Princeton's, but I currently have the 5V4 in my BF Pro (non reverb) and have used in Bassmans (with rectifier tube) , Vibrolux, Bandmasters etc.
I think going to a 5Y3 may be too much for a Super with 6L6's.
I think the "jj's..as i understand it they are basically 6L6's in 6v6 form" is a wildly distributed myth on the internet.. They sound like clean 6V6's to me and they are all I use now. I've had dozens of vintage 6V6's and still have some. But did a major sale of vintage tubes last year. Got tired of dealing with noisy vintage tubes. I want to "play"!

Not sure about the long bottle 5881's. They were widely used in Bassman's etc. The small bottle WGB are definitely less wattage and to my ears have a less harsh tone at lower volumes.
No reason you couldn't try the 6V6's in that Super. It may sound great with a bias and possibly a little tweaking. Try it, report back with what you want to change and we can help. The PI input cap can be changed to adjust the amp sound readily.

BTW, have you tried plugging into input 2? It's less loud.
Several years ago I had a 4 x 10 cab made for my Deluxe Reverb. It was killer sounding. However,just as big as a Super.

 

[boxocrap]

If I am understanding your goal correctly it’s to be able to get power amp breakup at less than stadium filling levels?

I’m assuming there is a reason using a good attenuator won’t work for you? I’m just curious why that isn’t your goto, especially since it could be used with any other amp, and you won’t have to modify a valuable vintage amp?

thx for replying..good question..heres the answer...i do have an attenuator it dosn't quite do what i wanted..and it dosen't do a 2 or 4 ohm load..only 8 and 16 ohm..my super ( i bought it new in 1970) has been modded a fair amount back from those days..no one or very few were thinking about vintage value back then.. i had several mods done over a couple yrs and all but one has worked out quite well..so much for it having much vintage value..but your suggestion would be the best one if it was a stock amp..and i could mod an attenuator to do 2 or 4 ohms or find one..i could mod the one i have but it's a proto and probably has or will have some vintage value at some point it works just fine on 8 and 16 ohm outputs..these posts of mine tend to get long in the tooth with the explanations..thx for reading

 

[telemnemonics]

I say: canoworms boxocrap!

I can't remove my own preferences cobbled together from the years I spent fighting the wrong amps trying to make them right...

 

[boxocrap]

I have used the various rectifiers in many BF amps. Mostly my Deluxe's, and Princeton's, but I currently have the 5V4 in my BF Pro (non reverb) and have used in Bassmans (with rectifier tube) , Vibrolux, Bandmasters etc.
I think going to a 5Y3 may be too much for a Super with 6L6's.
I think the "jj's..as i understand it they are basically 6L6's in 6v6 form" is a wildly distributed myth on the internet.. They sound like clean 6V6's to me and they are all I use now. I've had dozens of vintage 6V6's and still have some. But did a major sale of vintage tubes last year. Got tired of dealing with noisy vintage tubes. I want to "play"!

Not sure about the long bottle 5881's. They were widely used in Bassman's etc. The small bottle WGB are definitely less wattage and to my ears have a less harsh tone at lower volumes.
No reason you couldn't try the 6V6's in that Super. It may sound great with a bias and possibly a little tweaking. Try it, report back with what you want to change and we can help. The PI input cap can be changed to adjust the amp sound readily.

sounds like a plan..so..do i use the adapters i have..or just plug in the 6v6's and rebias?..ya i just wanna play too..it's always been like that but..for a long time i have been limited to this one amp ( not now thankfully) and have read a fair amount on do's and don'ts on supers...i'm not any kind of qualified person to go in there and start doing anything serious by changing much of the internals..if i could find a real schematic on how to do this..or one to build a circuit on a switch to go from 6l6 to 6v6..somehow?..i would go that way..i have a couple people who can read schematics and see whats required..i can read them and understand a fair amount but have zero skills at the type of surgery required to do the required mods..that and i don't see very well these days even with glasses..do you have any schematics that you could post to achieve this?..a switchable circuit that will allow 6l6 to 6v6 so that with a flip of a switch i can shut it down and pull the tubes put in another set and it all works just fine?

 

[boxocrap]

I say: canoworms boxocrap!

I can't remove my own preferences cobbled together from the years I spent fighting the wrong amps trying to make them right...

i've also been told i'm like a dog with a bone too..you are probably correct.. can o' worms.. but ( here we go) it's been bugging me for a few decades now..and i kinda need to know once and for all..it's always.. but what if i could?

 

[schmee]

sounds like a plan..so..do i use the adapters i have..or just plug in the 6v6's and rebias?..ya i just wanna play too..it's always een like that but..for a long time i have been limited to this one amp ( not now thankfully) and have read a fair amount on do's and don'ts on supers...i'm not any kind of qualified person to go in there and start doing anything serious by changing much of the internals..if i could find a real schematic on how to do this..or one to build a circuit on a switch to go from 6l6 to 6v6..somehow?..i would go that way..i have a couple people who can read schematics and see whats required..i can read them and understand a fair amount but have zero skills at the type of surgery required to do the required mods..that and i don't see very well these days even with glasses..do you have any schematics that you could post to achieve this?..a switchable circuit that will allow 6l6 to 6v6 so that with a flip of a switch i can shut it down and pull the tubes put in another set and it all works just fine?

I don't have anything like that.
Yes, just plug the 6V6's in, but you MUST rebias . Check the plate voltage if you can and bias accordingly.
I'd just try that much and see what you think. There could be more small changes to get the tone you want with 6V6's, which then could complicate creating an "easy changeover" scheme.. Hard to say.

 

[telemnemonics]

i've also been told i'm like a dog with a bone too..you are probably correct.. can o' worms.. but ( here we go) it's been bugging me for a few decades now..and i kinda need to know once and for all..it's always.. but what if i could?

Figure if you COULD properly run the SFSR with 6v6 you would drop the volume what?
2db?
Not sure what wattages would be but figuring RMS at clipping goes from 42w to 22w?
Is that really enough?

When I was near the end of my decades trying to force classic amps to doother stuff that what they did best, i figured it would be great to take three speakers and box them up in the basement then cover them with blankets and run a wire to whatever amp with the fourth speaker in it.
Not 1/4 the dbs but three out of four speaker are removed from the room and inaudible.
Even thought of burying a cab in the yard!
Or better still hide in in an annoying neighbors house!

 

[Nicko_Lps]

.i've got a "power soak" although they don't call it that..doesn't quite do what i want and won't handle a 2 or 4 ohm load..0nly 8-16..

The bugera PS1 is extremely cheap and have all 4-8-16 options!
The EL84 converters even in triode configuration which is less wattage did not help me, cant get past 1.5 inside a room with their...7-9 watts

Again, if you want a cheap amp at around 20 watts you can get the new marshall all tube heads, they have even FX loops but personally i would buy the 5 watt one if youre going to play only in your house. Other than that, even the 5 watt with the power reduction switch is lethally loud. Damn tubes, no matter what they always going to be loud!

 

[boxocrap]

Figure if you COULD properly run the SFSR with 6v6 you would drop the volume what?
2db?
Not sure what wattages would be but figuring RMS at clipping goes from 42w to 22w?
Is that really enough?

When I was near the end of my decades trying to force classic amps to doother stuff that what they did best, i figured it would be great to take three speakers and box them up in the basement then cover them with blankets and run a wire to whatever amp with the fourth speaker in it.
Not 1/4 the dbs but three out of four speaker are removed from the room and inaudible.
Even thought of burying a cab in the yard!
Or better still hide in in an annoying neighbors house!

it's not just dropping the loud factor down..it's the compression on the 6v6 tubes when they hit the "sweet" spot..as you know..a couple of 6v6 usually don't put out more than about 30 watts or so.at least that's what they were at one time i believe..6l6's can go significantly higher than that..when new my super did 40 or so..given the age of my sfsr..i suspect it may do on a good day..maybe 30 watts...so the idea here is with 6v6's i may be able to get it down lower and have the pw tubes overdriven ( not radically) at 20 watts ( not sure about the db levels) and i'm running it at 4 ohms not 2 so..i'm thinkiing i'm already lowering the power output by doing that.. so with 6v6 wouldn't i get it down a few more? i'm after a smooth power tube distortion that won't be super ( pardon the pun) loud and sound loud enough to drive the speakers so they move some air..

 

[telemnemonics]

it's not just dropping the loud factor down..it's the compression on the 6v6 tubes when they hit the "sweet" spot..as you know..a couple of 6v6 usually don't put out more than about 30 watts or so.at least that's what they were at one time i believe..6l6's can go significantly higher than that..when new my super did 40 or so..given the age of my sfsr..i suspect it may do on a good day..maybe 30 watts...so the idea here is with 6v6's i may be able to get it down lower and have the pw tubes overdriven ( not radically) at 20 watts ( not sure about the db levels) and i'm running it at 4 ohms not 2 so..i'm thinkiing i'm already lowering the power output by doing that.. so with 6v6 wouldn't i get it down a few more? i'm after a smooth power tube distortion that won't be super ( pardon the pun) loud and sound loud enough to drive the speakers so they move some air..

With a loud drummer a Deluxe Reverb lacks volume but here I think you still end up louder than a BFDR.
Really pretty loud once wound up to compressed saturation, but really worse or louder or less saturated compression due to the way too big OT and higher voltage PT in the SFSR.
That's my sense anyhow, YMMV!

 

[Lowerleftcoast]

i'm running it at 4 ohms not 2 so..i'm thinkiing i'm already lowering the power output by doing that.. so with 6v6 wouldn't i get it down a few more?

The 6V6 will be most efficient running the 4 Ohm load. It should stay the same volume vs running the 6L6 not as efficiently on the 4 Ohm load.

You already have a 4 Ohm speaker load into the 2 Ohm OT secondary, so that is covered. The high voltage can be addressed with JJ tubes. OK so it is doable.

It appears I am not the only one that has tried to change an amp with lower output tubes. Go ahead and try. The rest of us did. Mine all were put back to original, save one. I have 5881s in a Hot Rod Deluxe. I can't say it is any quieter but I like the sound better.