Yeah another tube question (Express 5:50)

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MikeW

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I have read way too many posts about preamp tube selctions with the various Boogie amps. What I am trying to do is tame some of the gain with the 5:50. I play mainly in church. I probably bought too much amp but hey I like it. Based on what I have read, I am thinking of putting 5751 tubes in V1, V2 and V3.........good or bad idea????

Thanks in advance for your opinions

Mike
 
MikeW said:
I have read way too many posts about preamp tube selctions with the various Boogie amps. What I am trying to do is tame some of the gain with the 5:50. I play mainly in church. I probably bought too much amp but hey I like it. Based on what I have read, I am thinking of putting 5751 tubes in V1, V2 and V3.........good or bad idea????

Thanks in advance for your opinions

Mike


what do you mean by "tame some of the gain".
If you mean less gain I don't get it.
All you have to do is turn down the gain pot.
The 5w setting should be perfect for small venue gigs like a Church.
What exactly are you trying to acheive tone wise.
And who makes 5751 tubes ?
 
Thanks for your reply.....I suppose I mean by taming some gain is for the preamp to have less gain whether it be in 5 or 50 watt mode.

A 5751 is a replacement for a 12ax7 but with about 2/3 the gain. Some other posters have reported using them in various other boogie amps. Maybe I should have posted in the 'tubes' section.
 
Thats stupid!

There is no need to tame down the gain. Log onto watford valves in the uk and they have cryo kits made in high gain packs or as clean gain packs which will tame down the gain on the express and induce bigger headroom for cleans and later distortion to appear. YOU NEED THAT CLEANER PREAMP SET WHICH IS SPECIFICALLY FOR THE EXPRESS. Im going in the other direction and purchasing the high gain cyro kit to induce tighter lows and highs with more gain.


The express was made to cover all bases....simply crank up the clean and blues modes if less gain is desired. Those are the modes you should be using.
Also try reducing the gain on the crunch to get alternative clean and blues sounds..
 
i went with eurotubes advice of the Standard grade 12AX7's in the pre amp position. the Mesa tubes seem harsh and higher gain.

i am a country player/classic rock player and needed to tame a F-30.

i also put an eminence private jack speaker in there. the difference of the tubes and the speaker is amazing!!

i like JJ preamp tubes in these small amps and i love Sovtek EL84's or EH EL84's for the power tubes.

different brands of 12AX7's will net different results.

let us know what you decide!!
 
MikeW said:
Thanks for your reply.....I suppose I mean by taming some gain is for the preamp to have less gain whether it be in 5 or 50 watt mode.

A 5751 is a replacement for a 12ax7 but with about 2/3 the gain. Some other posters have reported using them in various other boogie amps. Maybe I should have posted in the 'tubes' section.

Ok mike - I think I understand.

no wonder I've never heard of 5751 tubes. I've only ever tried to do the opposite. I stuck higher gain JJ tubes in my 5:50 :lol:

so just use the amp's clean channel on the 5w setting with the gain pot turned down low. Why isn't that your solution ?

The 5:50 is a very clean amp on channel 1. It's got a ton of headroom so it doesn't break up when you push the volume hard on channel 1. Its clean tones are possbily as good as any amp ever made. It's clean tones are on a par with the Lonestar and much better than the F series amps. So just cause something worked on a F-30 that doesn't help much IMHO. I can't see how sticking low gain 5751's in it will improve things either but give it a go
 
Yea I believe just giving it a go will be the best thing as well......60 bucks on some tubes is small potatoes compared to what the amp cost me. You are right....I am using the 5 watt channel a lot and using the clean channel which are some of the best cleans I have heard. I then use pedals to break it up cause I have a little more control there. What I am hoping to do is make the gain a little less responsive.....kinda like gotta turn the knob a little farther.....For my style of music I play the most and that would be contemporary christian and some older rock and blues, a little less 'aggression' would be good for me.....I think.

At any rate, I'll give it a try and report back......I will either be a genius or as Expresslover put it .....stupid.

Thanks
 
EXPRESSLOVER said:
Thats stupid!
Im going in the other direction and purchasing the high gain cyro kit to induce tighter lows and highs with more gain.

why using a lower gain tube stupid?
The gain pot controls the signal at the output of the v1 tube. Turning it down controls the level going to the next gain stage only. Leaving all components the same, the only way to lower the 1st stage tube gain is using a lower gain tube. Also for most amp you have no control over the gain of the 2nd and 3rd gain stages. However I wouldn't use lower gain tube in all positions, but either in 1st stage or later stage.
 
ja22y said:
EXPRESSLOVER said:
Thats stupid!
Im going in the other direction and purchasing the high gain cyro kit to induce tighter lows and highs with more gain.

why using a lower gain tube stupid?
The gain pot controls the signal at the output of the v1 tube. Turning it down controls the level going to the next gain stage only. Leaving all components the same, the only way to lower the 1st stage tube gain is using a lower gain tube. Also for most amp you have no control over the gain of the 2nd and 3rd gain stages. However I wouldn't use lower gain tube in all positions, but either in 1st stage or later stage.

Thanks for advice..it make sense... and will save me some money
 
Actually I'd only put that low gain tube in V2.
That's where doug from www.dougstubes.com advised me to put the high gain JJ tube. It did make a significant difference. :D
 
In general when you swapping tube, the most noticeable difference would be v1. Whether you like the result or not is another thing.
 
Hi MikeW,

Your question is not stupid at all.

I studied the amp's manual before writing this. What I know from my own experience is that 5751 will not make enough difference in gain for what you want to do. But if you want to try one, get a GE short grayplate, it won't break your bank and it has a wonderful tone. There is something to be said for twiddling knobs, but that can only help so much. Changing the gain in the preamp tubes also changes the way that the amp responds to a player in a way that knob tweaking can't.

Ebay is a great source for the tubes I am recommending, I get nearly all of my tubes there, and have a couple hundred or more in my collection, and my friends whose amps I have voiced from my vintage old stock collection prefer their tones after I get done...by far... sometimes you get lemons, but the more experience one gets buying there, the less often that happens.

Change out only one tube at a time. 12at7, cv4024, or 6201 (all the same same tube gain type) will do more of what you want. Put the 12at7's in V2, V1, and V4. That will cover most of the gain stages in the preamp and also cover the phase inverter tube as well. The phase inverter needs to have matched sections to work the best and give the best tone. The other positions don't require matched sections.

Start with v2, that oddly is where the first gain stages are, then if that is not enough stick a 12at7 in V1, that is where the next gain stages are. Newysurfer is right on that one. Finally, if that is not enough, stick a 12at7 in the phase inverter slot, (balanced sections). That will go a long way to taming the amp like you want, and you probably will still be able to get plenty dirty for your purposes if you want.

I love the Mullard cv4024, that tube is the one to get in balanced sections for your phase splitter slot, you can find them from serious tube dealers on ebay, but expect to pay more for one, they often go for over 40 bucks each. And yes, for the kind of money you spent on that amp it is a good idea to have some exceptioanally nice tubes, Mesa amps give back very well when you pimp them out. Other great choices are the Raytheon 12at7 blackplate, either the US Navy version with the yellow print and the "anchor" symbols, or the Raytheon red print triple mica blackplate, my all time fave. Other choices include Tungsol grayplate 12at7, and Sylvania triple mica 12at7 blackplate. All these are wonderful sounding, and most vintage 12at7's are often gotten for relatively dirt cheap.

Finally, Albert Einstein is credited with the saying that "Great spirits have always encountered violent opposition from mediocre minds..."
 
Someone please correct me on this, but I think that V1 is not really the first gain stage in clean mode.
 
Thank you very much for the work you put into your answer. I just happen to have 2 Mullard 12AT7 from a HiFi venture from a few years ago that still test practically new. I will follow your advice and give this a shot.
Again thanks

Mike

212Mavguy said:
Hi MikeW,

Your question is not stupid at all.

I studied the amp's manual before writing this. What I know from my own experience is that 5751 will not make enough difference in gain for what you want to do. But if you want to try one, get a GE short grayplate, it won't break your bank and it has a wonderful tone. There is something to be said for twiddling knobs, but that can only help so much. Changing the gain in the preamp tubes also changes the way that the amp responds to a player in a way that knob tweaking can't.

Ebay is a great source for the tubes I am recommending, I get nearly all of my tubes there, and have a couple hundred or more in my collection, and my friends whose amps I have voiced from my vintage old stock collection prefer their tones after I get done...by far... sometimes you get lemons, but the more experience one gets buying there, the less often that happens.

Change out only one tube at a time. 12at7, cv4024, or 6201 (all the same same tube gain type) will do more of what you want. Put the 12at7's in V2, V1, and V4. That will cover most of the gain stages in the preamp and also cover the phase inverter tube as well. The phase inverter needs to have matched sections to work the best and give the best tone. The other positions don't require matched sections.

Start with v2, that oddly is where the first gain stages are, then if that is not enough stick a 12at7 in V1, that is where the next gain stages are. Newysurfer is right on that one. Finally, if that is not enough, stick a 12at7 in the phase inverter slot, (balanced sections). That will go a long way to taming the amp like you want, and you probably will still be able to get plenty dirty for your purposes if you want.

I love the Mullard cv4024, that tube is the one to get in balanced sections for your phase splitter slot, you can find them from serious tube dealers on ebay, but expect to pay more for one, they often go for over 40 bucks each. And yes, for the kind of money you spent on that amp it is a good idea to have some exceptioanally nice tubes, Mesa amps give back very well when you pimp them out. Other great choices are the Raytheon 12at7 blackplate, either the US Navy version with the yellow print and the "anchor" symbols, or the Raytheon red print triple mica blackplate, my all time fave. Other choices include Tungsol grayplate 12at7, and Sylvania triple mica 12at7 blackplate. All these are wonderful sounding, and most vintage 12at7's are often gotten for relatively dirt cheap.

Finally, Albert Einstein is credited with the saying that "Great spirits have always encountered violent opposition from mediocre minds..."
 
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