Feel free to ask Myles

[myles_rose]

Originally posted by flagshipmile:

Myles, I know you are sick of hearing from me, but I have a problem with my Bivalve setup.

 

I am running a DOD bifet preamp (second) and a Danecho in the loop. The preamp is to boost my solos. I have tried the preamp 1rst and it is similar.

 

Anyways, tonight I had my singer plug and unplug the cords to the FX loop. I definately can notice a difference. It just seems more subtley compressed (more soupy) and not as in your face when I run through the loop. When the loop is unplugged it is killer.

Through the front of the amp I am running a crybaby and a phase 90. I am not having the problem there (to the best of knowledge).

 

Anyways I hate the idea of losing something after spending the coin to have a killer tone.

 

The bifet never messed with the tone when I had my Peavey Classic. I am confused as to why it does now (I mean when it is not ON). I tried a Boss digital delay instead of the Danecho and it sounded a bit more hissy. I am not sure if it may be the amp not liking the DOD bifet preamp.

 

I have already spent alot of money and I want this thing air tight.

 

I trust you and I know you are a Amp/Tube god!!

 

What should I do to accomplish my goal of great tone with effects through the loop of the Bivalve?

Bruce,

 

Unfortunately there is little you can do. Serial effects loops are known as "tone sucking" devices and this is why some folks go to a parallel effects loop which overcomes some disadvantages but then has their own.

 

What is done for Carl Verheyen is take the speaker out of his 50 watt Marshall as an example, run it to a THD HotPlate, take one output to his speaker cab and then the line out to his effects rack ... run his effects back into a second power amp (a 100 watt Marshall but we bypass the preamp of this amp) and this is the wet side of the live rig.

 

This is all explained in the bonus material on his latest DVD "Rumor Mill" which has some great performances but also a ton of technical bonus material and workshops.

 

http://www.carlverheyen.com/store.htm

[myles_rose]

Originally posted by rockincyanblues:

Myles,

 

One more 135 W Twin question, as I await delivery of my new power tubes and bias kit.

 

When I want absolute silence, I run without V5, the tremelo driver. But I do like my tremelo. Do you have a recomendation for a quiet tube?

GT-12AX7R - not gainy and very quiet. Great for effects loops too.

 

http://www.groovetubes.com/product.cfm?Product_ID=1166

[Gifthorse]

Ok one more easy question.

 

I don't have the budget of Carl unfortunately. I am already in the hole for buying this rig.

 

What about a VHT Valvulator. I think it is supposed to help with this problem. Are you aware of these and their functions?

[myles_rose]

Originally posted by flagshipmile:

Ok one more easy question.

 

I don't have the budget of Carl unfortunately. I am already in the hole for buying this rig.

 

What about a VHT Valvulator. I think it is supposed to help with this problem. Are you aware of these and their functions?

This is really a buffering device to put at the end of a bunch of stuff before hitting the input of an amp.

 

Not the solution to the problem.

[Caevan O’Shite]

Myles, would there be a feasable way for a competent, qualified tech to modify the effects-loop in a THD BiValve- perhaps tweaking some component values- to better suit a given, particular effects-unit?

 

-OR-

 

Vice-verse, mod the I/O of said effects-unit to better suit the 'loop of the BiValve?

 

Thanks for any ideas you might have!

[Gifthorse]

Interesting Cave, didn't think of that.

 

Thanks for forwarding my cause!!

 

Actually the tone isn't 'bad' through the loop. I feel like I lose about 8% of the tone.. I mean it still sounds great, but there is some loss.

 

It is annoying but if I hadn't had my singer unplug it and plug it back in, I wouldn't be as sensitive to it. I can hear little subtleties and it drives me nuts, but either way it is a world better sounding than my last amp setup.

 

That would rock if I could have Bruce egnater tweak my pedal to adjust something to make it more transparent.

 

The DOD through the loop has worked AWESOME through every amp I have tried. It totally adds the right stuff for a solo. LIttle bit of gain, same tone or more highs if you want, right amount of volume boost.

 

This is the first time I have seen it alter the tone. I love this amp though.

[Rhino Madness]

Originally posted by flagshipmile:

Interesting Cave, didn't think of that.

 

Thanks for forwarding my cause!!

 

Actually the tone isn't 'bad' through the loop. I feel like I lose about 8% of the tone.. I mean it still sounds great, but there is some loss.

 

It is annoying but if I hadn't had my singer unplug it and plug it back in, I wouldn't be as sensitive to it. I can hear little subtleties and it drives me nuts, but either way it is a world better sounding than my last amp setup.

 

That would rock if I could have Bruce egnater tweak my pedal to adjust something to make it more transparent.

 

The DOD through the loop has worked AWESOME through every amp I have tried. It totally adds the right stuff for a solo. LIttle bit of gain, same tone or more highs if you want, right amount of volume boost.

 

This is the first time I have seen it alter the tone. I love this amp though.

It could be that this is the first amp you're using that does not mask the difference in tone when the pedal is engaged. Or the fact that you are now using more of the power tube distortion.

 

Some food for thought:

1. When the power section is already saturated, sending a hotter signal mostly gives you more gain (as opposed to more volume);

2. Depending on the amount of power tube saturation you're using, putting a delay pedal before the power section might send everything to mush (you're sending twice the signal for the power tubes to distort).

 

You might have to rethink your signal chain so you have time-based FX (delay/reverb) after the power amp (either by using the included HotPlate signal out or by micing your speaker and then using an outboard processor and the PA or a second amp, etc).

 

YMMV but it's a different world out there once you're using power tube distortion as your main tone.

[myles_rose]

Originally posted by Caevan_O'Shite:

Myles, would there be a feasable way for a competent, qualified tech to modify the effects-loop in a THD BiValve- perhaps tweaking some component values- to better suit a given, particular effects-unit?

 

-OR-

 

Vice-verse, mod the I/O of said effects-unit to better suit the 'loop of the BiValve?

 

Thanks for any ideas you might have!

If you look inside of one of these there is a LOT of stuff. They are heavy PCB construction ... the traces are so heavy that cutting them takes a grinding tool.

 

You will gain nothing by modifying the way the loop in implemented. It has the best design and components available and will always retain the tone impacting aspects of any effects loop whether serial or parallel. If you do not have anything plugged in there then there is no issue.

 

You can use the isolated line out which is adjustable for level and come back to the effects return for a great tone as an option.

[Gifthorse]

You can use the isolated line out which is adjustable for level and come back to the effects return for a great tone as an option.

Cool, you mean use that like and effect out--

 

Pardon me for my ignorance, but I am assuming you mean using the line out, then in to the effect then out back into the return of the loop.

 

Unless you are just saying to use the amp as a preamp to a poweramp.

[myles_rose]

Originally posted by flagshipmile:

You can use the isolated line out which is adjustable for level and come back to the effects return for a great tone as an option.

Cool, you mean use that like and effect out--

 

Pardon me for my ignorance, but I am assuming you mean using the line out, then in to the effect then out back into the return of the loop.

 

Unless you are just saying to use the amp as a preamp to a poweramp.

Use the line out on your rear panel as the send for the effects rather than the effects send.

[Gifthorse]

Thanks again Myles. I will try this.

 

God it would rule if Dr.Z made an amp with a built in attenuator.

[myles_rose]

Originally posted by flagshipmile:

Thanks again Myles. I will try this.

 

God it would rule if Dr.Z made an amp with a built in attenuator.

I do not like lumping extra stuff in any amp. I prefer external attenuators when one is used. In the UV and BV they are cool as the amp was designed around the idea in the first place as one of the features. But ..... a great attenuator is really a pretty complex piece of gear on it's own like the GT SEII ..... http://www.groovetubes.com/product.cfm?Product_ID=1604 ...... which costs as much as a Univalve. Look inside of the SEII and you will see why ... especially that little black box that in in there.....

[Caevan O’Shite]

Hehhehh, that little black box of Aspen's... !!

 

I've got an ooold, late 70's/early '80s GT Electronics Speaker Emulator unit (the original one, no attenuation for external speakers, no 'loop, and the "pole-filter" EQ, instead of the "amp-style EQ"). It's fantastic for providing a line-out direct send from a tube-amp's speaker-out, with or without other "real" speakers connected.

 

I see that Harry Kolbe offers a separate, stand-alone attenuator that will either work along with his own "Silent Speaker" load-box/speaker emulator, *or* another one of the user's choosing.

 

Myles, what do you think of using the GTE Sp Emu in tandem with the Harry Kolbe attenuator?

 

Since I already know that I LOVE the reactive-loading characteristics of the GTE Sp Emu, I'm guessing that this would be a superior option to most attenuators out there?

[Corner Pocket]

Myles,

 

I've just come into possesion of a Gibson Minuteman GA-20 rvt.

 

Internet resources are thin, at best, on this amp. What are the things to fear on this amp, if any?

[myles_rose]

Originally posted by Caevan_O'Shite:

Hehhehh, that little black box of Aspen's... !!

 

I've got an ooold, late 70's/early '80s GT Electronics Speaker Emulator unit (the original one, no attenuation for external speakers, no 'loop, and the "pole-filter" EQ, instead of the "amp-style EQ"). It's fantastic for providing a line-out direct send from a tube-amp's speaker-out, with or without other "real" speakers connected.

 

I see that Harry Kolbe offers a separate, stand-alone attenuator that will either work along with his own "Silent Speaker" load-box/speaker emulator, *or* another one of the user's choosing.

 

Myles, what do you think of using the GTE Sp Emu in tandem with the Harry Kolbe attenuator?

 

Since I already know that I LOVE the reactive-loading characteristics of the GTE Sp Emu, I'm guessing that this would be a superior option to most attenuators out there?

I would never mix two attenuators.

[myles_rose]

Originally posted by rockincyanblues:

Myles,

 

I've just come into possesion of a Gibson Minuteman GA-20 rvt.

 

Internet resources are thin, at best, on this amp. What are the things to fear on this amp, if any?

Just make sure the tubes are fresh, clean and lube the pots, and retension the tube sockets.

 

Great amp!

[rsf1977]

hey Myles what are the groove tube equivalent to the 9th Gen Chinese 12AX7s?

[myles_rose]

Originally posted by rsf1977:

hey Myles what are the groove tube equivalent to the 9th Gen Chinese 12AX7s?

This IS the current GT12AX7C. This tooling is shared at Shuguang by GT and Magic Parts ... they are the main folks that fund this tooling.

[baronedo]

Myles,

I have a Fender Hot Rod Deville amp in the 2x 12 speaker configuration. I wanted to add an external 15 speaker cab for a little more bottom and tried one. The problem is that when the 15 speaker cab is connected to the amps external speaker jack, there is noticeably less volume going to the 15 than to the two 12s. An investigation and emails to Fender disclosed the problem is that the 15 is an 8 ohm speaker while the amps external speaker jack needs a 4 ohm speaker.

 

Is there any way to make this 15 8 ohm speaker cab work with my amp? Also, if I use the 15 as is (i.e. wired with the wrong impedance and getting less volume from it), is this bad for the amp?

[Caevan O’Shite]

If I may butt in-

 

Lancer-

 

The simplest and best solution is to simply use a 4 ohm 15" speaker, connected to the amp's extension speaker jack; you could put it in the same 15" cab, and hold on to the original 8 ohm speaker.

 

You could wire one of the 12" speakers and the 15" speaker in parallel, both connected to the main speaker-output of the amp, to yeild a total combined impedance of 4 ohms.

 

Of course, this would leave one of the two 12" speakers in the Hot Rod DeVille 2x12 unused.

 

-or-

 

you could connect a safe, reliable, suitable 8 ohm "dummy" load (like that in a Groove Tubes Speaker Emulator, THD Hot Plate, Dr. Z Airbrake, etc.) in parallel with the 8 ohm 15" speaker (both to the same extension speaker jack, in parallel, yeilding 4 ohms). This would allow for use of both twelves and the fifteen; think of the "dummy load" as a "silent partner".

 

But...

 

The simplest and best solution is still to simply use a 4 ohm 15" speaker, connected to the amp's extension speaker jack...

[myles_rose]

Originally posted by Caevan_O'Shite:

If I may butt in-

 

Lancer-

 

The simplest and best solution is to simply use a 4 ohm 15" speaker, connected to the amp's extension speaker jack; you could put it in the same 15" cab, and hold on to the original 8 ohm speaker.

 

You could wire one of the 12" speakers and the 15" speaker in parallel, connected to the main speaker-output of the amp, to yeild a total combined impedance of 4 ohms.

 

Of course, this would leave one of the two 12" speakers in the Hot Rod DeVille 2x12 unused.

 

Otherwise, you either need to simply change the 15" speaker to a 4 ohm model (swapping it out),

 

-or-

 

you could connect a safe, reliable, suitable 8 ohm "dummy" load (like that in a Groove Tubes Speaker Emulator, THD Hot Plate, Dr. Z Airbrake, etc.) in parallel with the 8 ohm 15" speaker (both to the same extension speaker jack, in parallel, yeilding 4 ohms).

 

But...

 

The simplest and best solution is still to simply use a 4 ohm 15" speaker, connected to the amp's extension speaker jack...

Excellent reply ... feel free to "butt in" anytime!

[Caevan O’Shite]

I've done all of the above wiring schemes before, and I've also owned a Fender Hot Rod DeVille 2x12, too!

[fantasticsound]

Quick question on behalf of another thread.

 

Is the popping sound observed when turning off an amplifier, some radios, etc. an immediate discharge of capacitors in the power amp section and is there a way to alleviate this to protect the speaker(s)?

 

I've had luck, as a way to treat the symptom, strumming my guitar while powering down an amp with this problem, but I'd like to know if there is a modification that would make this unnecessary.

 

My issues have always been with solid state amps, radios and the like, but the other thread was started based on this same problem occuring in a Peavey Classic 30 tube amp.

 

Thanks for any suggestions, Myles.

[myles_rose]

Originally posted by fantasticsound:

Quick question on behalf of another thread.

 

Is the popping sound observed when turning off an amplifier, some radios, etc. an immediate discharge of capacitors in the power amp section and is there a way to alleviate this to protect the speaker(s)?

 

I've had luck, as a way to treat the symptom, strumming my guitar while powering down an amp with this problem, but I'd like to know if there is a modification that would make this unnecessary.

 

My issues have always been with solid state amps, radios and the like, but the other thread was started based on this same problem occuring in a Peavey Classic 30 tube amp.

 

Thanks for any suggestions, Myles.

There are a number of amps that are notorious for this and you can put a cap in circuit but in the end it is not really an issue or strain on the speakers. My Deluxe Reverb does this quite loudly but the amp and speaker have been fine for longer than many of the folks in this forum have been alive!

[Gifthorse]

Myles, I ran the output from my Bivalve to the delay and preamp boost and then back into the return and nothing happened.

 

I mean, no signal

 

I tried to run the preamp through the front and it didn't have the same volume boost effect. It got a bit louder but with more distortion and hiss.

 

Thanks

[fantasticsound]

Originally posted by myles111:

...There are a number of amps that are notorious for this and you can put a cap in circuit but in the end it is not really an issue or strain on the speakers. My Deluxe Reverb does this quite loudly but the amp and speaker have been fine for longer than many of the folks in this forum have been alive!

Thanks for the reply. FWIW, the owner of the Classic 30 ordered a new tube which appears to have solved his pop.

 

I guess all I can do to avoid beating up my eardrums (as an engineer I particularly avoid such noise) is to keep strumming the guitar until it's off. That seems to dissipate the stored energy without the loud pop.

 

Thanks for clearing that up.

[Corner Pocket]

Myles,

 

My tubes and bias tool just came in. My 135 watt Twin has been modified such that the "output tubes matching" pot is now a bias pot, and the "hum balance" pot has been taken out of the loop, and replaced with a resistor network/grid directly from the transformer.

 

I'm thinking that this process isn't rocket surgery, and I should be OK.

 

Ta very much for your help to this board in general, and me in particular.

[myles_rose]

Originally posted by flagshipmile:

Myles, I ran the output from my Bivalve to the delay and preamp boost and then back into the return and nothing happened.

 

I mean, no signal

 

I tried to run the preamp through the front and it didn't have the same volume boost effect. It got a bit louder but with more distortion and hiss.

 

Thanks

The output of the line out is meant for a high impedance device so this works on some effects but not on others.

 

Be sure to use line level and not instrument level on the switch on the back.

[myles_rose]

Originally posted by fantasticsound:

Originally posted by myles111:

...There are a number of amps that are notorious for this and you can put a cap in circuit but in the end it is not really an issue or strain on the speakers. My Deluxe Reverb does this quite loudly but the amp and speaker have been fine for longer than many of the folks in this forum have been alive!

Thanks for the reply. FWIW, the owner of the Classic 30 ordered a new tube which appears to have solved his pop.

 

I guess all I can do to avoid beating up my eardrums (as an engineer I particularly avoid such noise) is to keep strumming the guitar until it's off. That seems to dissipate the stored energy without the loud pop.

 

Thanks for clearing that up.

You are very welcome.

[myles_rose]

Originally posted by rockincyanblues:

Myles,

 

My tubes and bias tool just came in. My 135 watt Twin has been modified such that the "output tubes matching" pot is now a bias pot, and the "hum balance" pot has been taken out of the loop, and replaced with a resistor network/grid directly from the transformer.

 

I'm thinking that this process isn't rocket surgery, and I should be OK.

 

Ta very much for your help to this board in general, and me in particular.

You will be fine and dandy. Lots of folks have this mod and it is easy and works great.

 

Happy playing! LOUD AMP!