Feel free to ask Myles

[JasonDW]

Hey Myles,

I bought a new set of tubes for my Mesa Boogie Subway Rocket (2xEL84, 4x12AX7). They're groove tubes to replace the stock mesa boogie branded tubes that came with the amp 10 or so years ago. I poped the tubes in this evening and played for a while before it occured to me that perhaps I was supposed to have the amp rebiased since I switched brands, even though I didn't switch tube types. My questions are am I asking for trouble by not having the amp rebiased even though I replaced EL84s with EL84s and how would I know if I had a problem (would it be obvious)?

Thanks,

Jason

[myles_rose]

hey myles can recommend a good 1x15 or 2x15 cab for a peavey 6505 For metal tones. I want to run it along side a dual recto with a recto 4x12. we are trying out a no bass player setup and tring to dig further into the low end of the 2 guitars

 

Can't really help you here ... I am sorry.

 

This is really personal preference.

 

I will say I love the Emenance legend 15" speaker a lot though as a driver.

 

 

[myles_rose]

Hey Myles,

I bought a new set of tubes for my Mesa Boogie Subway Rocket (2xEL84, 4x12AX7). They're groove tubes to replace the stock mesa boogie branded tubes that came with the amp 10 or so years ago. I poped the tubes in this evening and played for a while before it occured to me that perhaps I was supposed to have the amp rebiased since I switched brands, even though I didn't switch tube types. My questions are am I asking for trouble by not having the amp rebiased even though I replaced EL84s with EL84s and how would I know if I had a problem (would it be obvious)?

Thanks,

Jason

 

 

Jason,

 

Your amp is cathode biased ... self biasing.

 

As long as the tubes are in the mid range ... 4-7 ... the amp will sound great and have the best tube life.

 

1-3 will run cold and sound grainy.

 

8-10 will run very hot, sound harsh, and have very short tube life.

 

At 300 hours of playing if you change output tubes again you will notice a big improvement that you did not even realize was going on from a standpoint of fube and tone degradation.

 

In Brad Paisley's amps we change the output sets every ten or so shows ... every 30 hours ... and notice a change.

 

The again, some folks run EL84 tubes for years and don't seem to mind the loss of performance or tone.

 

 

[bennyguitfiddle]

Hi Myles,

I seen in some early post you gave advise to tame an amp.

I own a mesa boogie studio caliber. a little 20 watt gem.

I love everything about this amp but I would like to tame the

clean channel. get a little more volume before it breaks up.

but I still want it to break up a little if ya know what i mean.

thank for any advise you can give.

 

 

Put a 5751 in V1. If that is not enough then a 12AY7.

 

 

 

so I put in a 5751 and all I can say is wow thanks man

 

what would happen if i replace all the preamp with 5751's

 

also I need to replace the power tubes

I think this amp is auto biasing too

 

the book say you have to buy mesa tubes but can I

get groove tubes?? they seem a little more quailty.

 

 

 

[JasonDW]

Hey Myles,

I bought a new set of tubes for my Mesa Boogie Subway Rocket (2xEL84, 4x12AX7). They're groove tubes to replace the stock mesa boogie branded tubes that came with the amp 10 or so years ago. I poped the tubes in this evening and played for a while before it occured to me that perhaps I was supposed to have the amp rebiased since I switched brands, even though I didn't switch tube types. My questions are am I asking for trouble by not having the amp rebiased even though I replaced EL84s with EL84s and how would I know if I had a problem (would it be obvious)?

Thanks,

Jason

 

 

Jason,

 

Your amp is cathode biased ... self biasing.

 

As long as the tubes are in the mid range ... 4-7 ... the amp will sound great and have the best tube life.

 

1-3 will run cold and sound grainy.

 

8-10 will run very hot, sound harsh, and have very short tube life.

 

At 300 hours of playing if you change output tubes again you will notice a big improvement that you did not even realize was going on from a standpoint of fube and tone degradation.

 

In Brad Paisley's amps we change the output sets every ten or so shows ... every 30 hours ... and notice a change.

 

The again, some folks run EL84 tubes for years and don't seem to mind the loss of performance or tone.

 

 

Myles, thanks so much for the reply. The amp really does seem to have renewed life with the new tubes. Unfortunately, I am noticing a very subtle "crackling" noise in the clean channel that wasn't there before. Is that something I should be concerned about? Is there a burn-in time with new tubes? By the way, the new tubes have a rating of (7).

Thanks again,

Jason

[myles_rose]

Hi Myles,

I seen in some early post you gave advise to tame an amp.

I own a mesa boogie studio caliber. a little 20 watt gem.

I love everything about this amp but I would like to tame the

clean channel. get a little more volume before it breaks up.

but I still want it to break up a little if ya know what i mean.

thank for any advise you can give.

 

 

Put a 5751 in V1. If that is not enough then a 12AY7.

 

 

 

so I put in a 5751 and all I can say is wow thanks man

 

what would happen if i replace all the preamp with 5751's

 

also I need to replace the power tubes

I think this amp is auto biasing too

 

the book say you have to buy mesa tubes but can I

get groove tubes?? they seem a little more quailty.

 

 

 

Preamp tubes in V1 and the phase inverter if 5751's would yield more clean headroom.

 

As far as output sets and Mesa to GT conversion look here:

 

http://www.guitaramplifierblueprinting.com/Rating.html

 

 

[myles_rose]

Hey Myles,

I bought a new set of tubes for my Mesa Boogie Subway Rocket (2xEL84, 4x12AX7). They're groove tubes to replace the stock mesa boogie branded tubes that came with the amp 10 or so years ago. I poped the tubes in this evening and played for a while before it occured to me that perhaps I was supposed to have the amp rebiased since I switched brands, even though I didn't switch tube types. My questions are am I asking for trouble by not having the amp rebiased even though I replaced EL84s with EL84s and how would I know if I had a problem (would it be obvious)?

Thanks,

Jason

 

 

Jason,

 

Your amp is cathode biased ... self biasing.

 

As long as the tubes are in the mid range ... 4-7 ... the amp will sound great and have the best tube life.

 

1-3 will run cold and sound grainy.

 

8-10 will run very hot, sound harsh, and have very short tube life.

 

At 300 hours of playing if you change output tubes again you will notice a big improvement that you did not even realize was going on from a standpoint of fube and tone degradation.

 

In Brad Paisley's amps we change the output sets every ten or so shows ... every 30 hours ... and notice a change.

 

The again, some folks run EL84 tubes for years and don't seem to mind the loss of performance or tone.

 

 

Myles, thanks so much for the reply. The amp really does seem to have renewed life with the new tubes. Unfortunately, I am noticing a very subtle "crackling" noise in the clean channel that wasn't there before. Is that something I should be concerned about? Is there a burn-in time with new tubes? By the way, the new tubes have a rating of (7).

Thanks again,

Jason

 

 

Crackling is usually a preamp tube issue.

 

If preamp tubes were not changed and only output tubes were changed have the output tubes replaced under warranty.

 

 

[Sauce]

Hey Myles sorry to bug you, but I was just curious. A few posts earlier you said power tubes should be changed after 300 hours of playing. How often should preamp tubes be changed? Thanks in advance.

[myles_rose]

Hey Myles sorry to bug you, but I was just curious. A few posts earlier you said power tubes should be changed after 300 hours of playing. How often should preamp tubes be changed? Thanks in advance.

 

 

On power tubes, that 300 hour figure was for cathode biased EL84 amps of some designs ... not all of them by all means.

 

On 6L6 amps such as a Fender Twin Reverb, their output tubes can last 5000-6000 at typical levels for these amps. EL34 amps that are grid biased can exceed 3000 hours.

 

Preamp tubes ..... they can last for decades. The exception is the phase inverter. This little guy is hard worked and pushes the output section. I check these whenever I am in any amp and make sure it is within 20% of design spec or toss it when it has a transconductance below 1400 or DC plate current of less the 1.0 milliamps.

 

 

[Sauce]

Hmmm real interesting. Thanks a lot Myles.

[bennyguitfiddle]

Hi Myles,

I seen in some early post you gave advise to tame an amp.

I own a mesa boogie studio caliber. a little 20 watt gem.

I love everything about this amp but I would like to tame the

clean channel. get a little more volume before it breaks up.

but I still want it to break up a little if ya know what i mean.

thank for any advise you can give.

 

 

Put a 5751 in V1. If that is not enough then a 12AY7.

 

 

 

so I put in a 5751 and all I can say is wow thanks man

 

what would happen if i replace all the preamp with 5751's

 

also I need to replace the power tubes

I think this amp is auto biasing too

 

the book say you have to buy mesa tubes but can I

get groove tubes?? they seem a little more quailty.

 

 

 

Preamp tubes in V1 and the phase inverter if 5751's would yield more clean headroom.

 

As far as output sets and Mesa to GT conversion look here:

 

http://www.guitaramplifierblueprinting.com/Rating.html

 

which one is the phase inverter??

and do they go in order?? v1 v2 v3 ect....

the valve closest to the input jack is v1 i'm guessing.

cause it's the one that seemed to clean the amp up the most.

 

[myles_rose]

Hi Myles,

I seen in some early post you gave advise to tame an amp.

I own a mesa boogie studio caliber. a little 20 watt gem.

I love everything about this amp but I would like to tame the

clean channel. get a little more volume before it breaks up.

but I still want it to break up a little if ya know what i mean.

thank for any advise you can give.

 

Phase inverter is farthest from the input jack.

 

5751 in the PI.

 

#6 on the output tubes

 

 

 

Put a 5751 in V1. If that is not enough then a 12AY7.

 

 

 

so I put in a 5751 and all I can say is wow thanks man

 

what would happen if i replace all the preamp with 5751's

 

also I need to replace the power tubes

I think this amp is auto biasing too

 

the book say you have to buy mesa tubes but can I

get groove tubes?? they seem a little more quailty.

 

 

 

Preamp tubes in V1 and the phase inverter if 5751's would yield more clean headroom.

 

As far as output sets and Mesa to GT conversion look here:

 

http://www.guitaramplifierblueprinting.com/Rating.html

 

which one is the phase inverter??

and do they go in order?? v1 v2 v3 ect....

the valve closest to the input jack is v1 i'm guessing.

cause it's the one that seemed to clean the amp up the most.

[bennyguitfiddle]

thank for the great info !!

 

my amp is a clean machine now!

[Zephyr]

Hello again Myles,

 

Lately I was browsing for some replacement speakers, because my current driver (Jensen C12K) is very harsh. I was wondering if you could give me your opinion on the following speakers, or if you could uncover some hidden gems, that would be good too.

 

Anyway, i am looking for a speaker that can deliver a smooth, warm, punchy sound, with smooth breakup, that doesn't ever sound harsh. I have my selection narrowed down to:

 

1) The Eminence GB128:

http://www.musiciansfriend.com/product/Eminence-Legend-GB128-Guitar-Speaker?sku=667700

 

2) The Celestion G12H-30:

http://www.musiciansfriend.com/product/Celestion-G12-H-Guitar-Speaker?sku=660267

 

Yet again, if you have any suggesstions, it would be much appreciated.

 

Thanks

[myles_rose]

Hello again Myles,

 

Lately I was browsing for some replacement speakers, because my current driver (Jensen C12K) is very harsh. I was wondering if you could give me your opinion on the following speakers, or if you could uncover some hidden gems, that would be good too.

 

Anyway, i am looking for a speaker that can deliver a smooth, warm, punchy sound, with smooth breakup, that doesn't ever sound harsh. I have my selection narrowed down to:

 

1) The Eminence GB128:

http://www.musiciansfriend.com/product/Eminence-Legend-GB128-Guitar-Speaker?sku=667700

 

2) The Celestion G12H-30:

http://www.musiciansfriend.com/product/Celestion-G12-H-Guitar-Speaker?sku=660267

 

Yet again, if you have any suggesstions, it would be much appreciated.

 

Thanks

 

An AlNiCO speaker will be smoother.

 

Both the speakers you mention are nice but in the end it is personal taste and preference.

 

What amp?

 

 

[Zephyr]

a Fender Deluxe Reverb Reissue. It truly is a nice amp, but the stock speaker really hinders it.

 

Are there any alnico speakers that have a operating capacity of 22 watts or more? and are not overly expensive?

[myles_rose]

a Fender Deluxe Reverb Reissue. It truly is a nice amp, but the stock speaker really hinders it.

 

Are there any alnico speakers that have a operating capacity of 22 watts or more? and are not overly expensive?

 

 

There are lots .... look at the Celestion page for the gold if you want high power capacity.

 

Maybe pricy but there is a reason why.

 

I prefer the blue ... has a 15 watt and 30 watt peak capacity and I know a lot of folks using these in the original Deluxe Reverb ... it is about as good as it gets and at 3dB higher efficiency than the stock speaker it is the same as doubling your wattage right off the bat.

 

But .... if you have the stock Sovtek preamp tubes this is a big problem from the get go .... and check your bias ... it may be off as is common at times. Too cold and things are grainy ... too hot and things are harsh.

 

The Jensen is a great speaker and it may just be the tubes and bias.

 

If you don't like the Vox Blue in a Deluxe Reverb then that amp is not for you as it does not get much better than that.

 

 

 

 

[Zephyr]

Good point Myles, however, i'm pretty sure it is the speaker, as i have Groove Tubes in there. But it could never hurt to check, thanks Myles.

[myles_rose]

Good point Myles, however, i'm pretty sure it is the speaker, as i have Groove Tubes in there. But it could never hurt to check, thanks Myles.

 

Fender uses the Sovtek 12AX7 WA or WC as standard issue. There are many better 12AX7 types at GT and from other vendors.

 

They are great amps for the $$$$ but it is a matter of economics for Fender in this amp price range.

 

 

 

 

 

[Mumbodave]

Hey Myles,

 

One of the poweramp tubes in my amp has blown! I own a H&K Duotone Head (100W) which currently houses 4 TAD EL34B-STR tubes. How many of the EL34s do I need to replace (the amp was made in 2003)? Does it matter which manufacturer I buy the tubes from (I was thinking of getting some Rubies)? Do they need to be EL34B-STRs for me to not need to bias them? What does biasing mean (and can I do it from home?!)?!

 

Thankyou for your time, and apologies for the myriad of questions!

 

Dave

[myles_rose]

Hey Myles,

 

One of the poweramp tubes in my amp has blown! I own a H&K Duotone Head (100W) which currently houses 4 TAD EL34B-STR tubes. How many of the EL34s do I need to replace (the amp was made in 2003)? Does it matter which manufacturer I buy the tubes from (I was thinking of getting some Rubies)? Do they need to be EL34B-STRs for me to not need to bias them? What does biasing mean (and can I do it from home?!)?!

 

Thankyou for your time, and apologies for the myriad of questions!

 

Dave

 

 

NEVER replace a single output tube. You need to replace the entire quad with a matched quad.

 

You also need to check the bias unless it is the same EL34 type of the same rating and since it is a Ruby it did not carry a rating so therefore .... you need to rebias.

 

If you have to ask what biasing means right off the bat I would tell you to take the amp to a tech. You can easily bias at home with the proper inexpensive tools but from what you have said here, and the leathal voltages that you would be exposed to, I strongly suggest you take the amp to a tech.

 

You also need to change output tubes long before they fail.

 

 

 

 

[ToadMeister]

Miles,

 

When I plug a digital delay and a chorus pedal into the effects loop of my Rivera Clubster I get a noticeable drop in volume and clarity. It has a muffled quality to it. Almost like a heavy blanket over the speaker.

 

Using the same guitar and cords I plug the same effects into my Mesa Boogie Mark III effects loop and I have no problems. I have new tubes in both amps. Any suggestions?

 

Thanks,

 

ToadMeister

 

[myles_rose]

Miles,

 

When I plug a digital delay and a chorus pedal into the effects loop of my Rivera Clubster I get a noticeable drop in volume and clarity. It has a muffled quality to it. Almost like a heavy blanket over the speaker.

 

Using the same guitar and cords I plug the same effects into my Mesa Boogie Mark III effects loop and I have no problems. I have new tubes in both amps. Any suggestions?

 

Thanks,

 

ToadMeister

 

 

Different effects loop levels.

 

Call Rivera ... they may have an idea or two.

 

 

[JonathanD]

I will look through the thread but pages are opening slow for me this morning in the anus of america.

I need some advice on retubing a fender bandmaster quickly. The local tech cant get it done by this weekends gigs.

Long story short, vibrations/tapping were producing distortion through the amp. We waited for it to cool and I pushed the tubes back in. Then we tried it again and no distortion. Should We Retube it? If so, can I put a matched set of the same kind of power tube in and not have to have the bias set for 2 gigs? Or is that still to long to wait? How does a bassist check the bias? Does that make me a bias bassist?

 

Thank you Myles. And if you dont wee this by friday at 6pm, dont worry about it.

Jonathan

[JonathanD]

A few other questions...

At what point in this thread did you say to yourself "what the hell was I thinking"

Jonathan

[myles_rose]

I will look through the thread but pages are opening slow for me this morning in the anus of america.

I need some advice on retubing a fender bandmaster quickly. The local tech cant get it done by this weekends gigs.

Long story short, vibrations/tapping were producing distortion through the amp. We waited for it to cool and I pushed the tubes back in. Then we tried it again and no distortion. Should We Retube it? If so, can I put a matched set of the same kind of power tube in and not have to have the bias set for 2 gigs? Or is that still to long to wait? How does a bassist check the bias? Does that make me a bias bassist?

 

Thank you Myles. And if you dont wee this by friday at 6pm, dont worry about it.

Jonathan

 

If we are talking blackface bandmaster, and the bias has never been changed from stock, a set of 6L6CHP, 6L6GE, 5881C, 6L6B® in a #5-6 rating could be put in the amp with the stock bias.

 

 

[Guitarzan]

Myles, i have an old Traynor Custom reverb 50 watt head (YSR1).

when i first got it it was prone to excessive crackling. i assumed it was the caps. so i set it aside in the basement. later a friend was working on an amp and we temporarily borrowed the el34's to try them in his amp. after i replaced my tubes i noticed the crackling was gone. after a few weeks it was back again. the other day (months later) i was trying the head with another cab and tried wiggling the power tubes a bit to seat them good, and it fired up without the crackling. am i safe in assuming the caps are fine and my problem is the sockets need to be cleaned and retensioned?

or can caps act fine once they drain a bit?

 

[PBBPaul]

Myles,

 

As a general principle; If an amp has a multi-tapped output transformer with 4/8/16 ohm taps, is it OK to simultaneously run say, a 4 ohm cabinet and a 16 ohm cabinet from the apppropriate taps? Or should one limit oneself to only one tap at a time?

 

Thanks,

 

Paul

[myles_rose]

Myles, i have an old Traynor Custom reverb 50 watt head (YSR1).

when i first got it it was prone to excessive crackling. i assumed it was the caps. so i set it aside in the basement. later a friend was working on an amp and we temporarily borrowed the el34's to try them in his amp. after i replaced my tubes i noticed the crackling was gone. after a few weeks it was back again. the other day (months later) i was trying the head with another cab and tried wiggling the power tubes a bit to seat them good, and it fired up without the crackling. am i safe in assuming the caps are fine and my problem is the sockets need to be cleaned and retensioned?

or can caps act fine once they drain a bit?

 

 

You are right on the money with your plan

 

 

[myles_rose]

Myles,

 

As a general principle; If an amp has a multi-tapped output transformer with 4/8/16 ohm taps, is it OK to simultaneously run say, a 4 ohm cabinet and a 16 ohm cabinet from the apppropriate taps? Or should one limit oneself to only one tap at a time?

 

Thanks,

 

Paul

 

One cab at a time.

 

You can though, take two 8 ohm cabs as an example and plug a parallel Y adaptor into the 4 ohm tap.

 

Or .... two 16 ohm cabs into the parallel adaptor and plug that into the 8 ohm tap.