Feel free to ask Myles

[RocketRick]

I'm wondering about making a device I can use to play the 16ohm 1960AX cab with the 8oum output frm the Mesa amp.

 

Place a 16-ohm resistor in series with the amp = 8-ohm load.

 

Only thing I see is the ALL of the load won;'t be reactive.

 

Ideas...thoughts? Dumb or?

[myles_rose]

It is C6, you see it just below the output transformer

 

I have no idea. I am on the road at the moment so will look when I have a chance.

[myles_rose]

I'm wondering about making a device I can use to play the 16ohm 1960AX cab with the 8oum output frm the Mesa amp.

 

Place a 16-ohm resistor in series with the amp = 8-ohm load.

 

Only thing I see is the ALL of the load won;'t be reactive.

 

Ideas...thoughts? Dumb or?

 

 

Just plug the 16 ohm cab into the 8 ohm tap ... no issues going higher. Do not plug a 4 ohm cab though into an 8 ohm tap.

 

 

[RocketRick]

My tech here said I will loose 1/2 the power.

 

He said the best thing is to wire the speakers so that 2 pair are in series and then each series pair in parallel for a total of 8-ohms.

 

That way I can use the cab with all amps.

[Bluesape]

Hey Myles,

 

Do ya know anything about these small heads from Vox and Burris? 15 & 18 watts, lookin' really hot in the mag! Any insights?

[myles_rose]

Hey Myles,

 

Do ya know anything about these small heads from Vox and Burris? 15 & 18 watts, lookin' really hot in the mag! Any insights?

 

I have not been inside of either.

[picker]

Hey Myles,

I was dinking around the web in my usual scattered way, when I ran acoss something that piqued my curiosity.

There is, apparently, an octal type beam power tube designated the 6K6 GT. Now being the slack-jawed whammy-handle jockey I am, there is probably no reason why I should ever have heard of it before, but knowing tht 6L6s and 6V6s are used in some of my favorite guitar amps, it made me wonder why I never heard of the 6K6 in one before, especially when I run across this guy saying they are available for 3 to 5 bucks each!

 

Looking further, I found that Kendrick is selling them for $25 each. So what is the rest of the story, Myles? What would a guitar amp with 6K6s sound like?

[myles_rose]

Hey Myles,

I was dinking around the web in my usual scattered way, when I ran acoss something that piqued my curiosity.

There is, apparently, an octal type beam power tube designated the 6K6 GT. Now being the slack-jawed whammy-handle jockey I am, there is probably no reason why I should ever have heard of it before, but knowing tht 6L6s and 6V6s are used in some of my favorite guitar amps, it made me wonder why I never heard of the 6K6 in one before, especially when I run across this guy saying they are available for 3 to 5 bucks each!

 

Looking further, I found that Kendrick is selling them for $25 each. So what is the rest of the story, Myles? What would a guitar amp with 6K6s sound like?

 

 

Very similar to a 6V6 but a bit less power ... sound a bit different ... used in the original Fender stand alone reverb units. No reason to use in a 6V6 equipped amp.

 

 

[Caevan O’Shite]

Hey, Myles, here's a question that's a little different from what you usually see here; please bear with me!

 

One of my pedals (Octave-X) has an odd effect (no pun intended) on another (Sustainiac Model C) that's upstream of it, and supposed to be working in parallel; I'm not talking about it affecting the signal from there on, but in this supposedly parallel, isolated "loop" of sorts...

 

I have a Sustainiac Model C feedback-sustainer- sort of a "pedal"- which works by taking the signal from the guitar and amplifies it to drive a small, vibrating transducer that clamps onto the headstock to induce controlled feedback. (Works great! Love it!)

 

An out jack from the pedal provides an un-affected signal from the guitar, to send on to other pedals, amp, etc. So it's like a little parallel side-chain loop, parallel to everything else (with the exception of the way the feedback goes from the guitar to everything downstream).

 

My entire headphone/direct rig's signal-chain goes:

 

Peterson 'StroboStomp' tuner >

 

Sustainiac (sends tapped-off signal to transducer, and straight-signal on to output) >

 

Fulltone 'Clyde Deluxe' wah >

 

MXR 'Blue Box' weird two-octave-down distortion/fuzz >

 

J. Everman 'Octave-X' octave-up fuzz >

 

Radial Tonebone 'Plexitube' tube/ss distortion >

 

DigiTech 'GNX4' modeler/worstation >

 

mixer/headphone-amp/PC/etc.

 

Whenever I kick in the Octave-X (a hot-rodded Octavia-style octave-fuzz with a beefed-up internal 18v ps working from any 9v battery or 9v "wart"), it affects the signal sent from the Sustainiac pedal to its transducer on the guitar's headstock- no matter if there's ANYTHING on or even connected downstream of the Octave-X, it has nothing to do with souind from speakers or headphones or anything from the Octave-X onward;

 

-you can hear the transducer (and the wood and strings of the guitar itself) vibrating away, and as soon as you step down on the footswitch of the Octave-X, it diminishes the overall strength of the feedback being sent to the guitar from the Sustainiac pedal, varying with what note and harmonic-overtones are feeding-back and sustaining. Some notes immediately fade out when the Oct-X is switched on, others merely drop a little, but none are UN-affected by it.

 

Switch the Octave-X off, and the feedback-signal from the Sustainiac pedal to the transducer on the guitar's headstock INSTANTLY goes back to full-strength.

 

Why would this be happening? Some sort of impedance weirdness?

 

Is it something that can be fixed?

[Changeling01960]

Hi Myles:

 

I have a couple of questions regarding amp wattage. I am trying to educate myself regarding amps. When I was singing in bands back in the 80's my gutiarists usually had either 50w or 100w stacks and also a small 10-15 watt amp they used for practicing/writing but never for rehearsing or gigs because they were no way near powerfull enough. A lot of the beginner/practice combo amps are rated 10w-15w-25w and it looks like the cost is somewhat determined by how powerful they are but for the most part they seem to fall in the $100-$150 range.

 

I was doing some comparison and looked at Fender Champs, which I remember being used by a lot of guys in the 60's & 70's for studio work anyway, not sure if they were used on stage. They run somwhere in the $300-$400 range and I was surprised to find out that they are 15 watts.

 

These are probably a silly questions, but here goes:

Are amps like the Fender Champ strictly studio amps only that would have to be run through a PA if used live and the cost difference due to the quality of the compnents and sound?

 

Is there a difference in power between solid state and tube amps of the same wattage rating? Also, is there a difference in volume due to how many speakers the head is driving so that a more wattage is needed to achieve the same amount of volume with a full stack vs a half stack vs a combo?(I remember some guys opting for 50w over 100w because they got more distortion/crunch at the same volume)

 

Thanks!

 

[myles_rose]

Hey, Myles, here's a question that's a little different from what you usually see here; please bear with me!

 

One of my pedals (Octave-X) has an odd effect (no pun intended) on another (Sustainiac Model C) that's upstream of it, and supposed to be working in parallel; I'm not talking about it affecting the signal from there on, but in this supposedly parallel, isolated "loop" of sorts...

 

I have a Sustainiac Model C feedback-sustainer- sort of a "pedal"- which works by taking the signal from the guitar and amplifies it to drive a small, vibrating transducer that clamps onto the headstock to induce controlled feedback. (Works great! Love it!)

 

An out jack from the pedal provides an un-affected signal from the guitar, to send on to other pedals, amp, etc. So it's like a little parallel side-chain loop, parallel to everything else (with the exception of the way the feedback goes from the guitar to everything downstream).

 

My entire headphone/direct rig's signal-chain goes:

 

Peterson 'StroboStomp' tuner >

 

Sustainiac (sends tapped-off signal to transducer, and straight-signal on to output) >

 

Fulltone 'Clyde Deluxe' wah >

 

MXR 'Blue Box' weird two-octave-down distortion/fuzz >

 

J. Everman 'Octave-X' octave-up fuzz >

 

Radial Tonebone 'Plexitube' tube/ss distortion >

 

DigiTech 'GNX4' modeler/worstation >

 

mixer/headphone-amp/PC/etc.

 

Whenever I kick in the Octave-X (a hot-rodded Octavia-style octave-fuzz with a beefed-up internal 18v ps working from any 9v battery or 9v "wart"), it affects the signal sent from the Sustainiac pedal to its transducer on the guitar's headstock- no matter if there's ANYTHING on or even connected downstream of the Octave-X, it has nothing to do with souind from speakers or headphones or anything from the Octave-X onward;

 

-you can hear the transducer (and the wood and strings of the guitar itself) vibrating away, and as soon as you step down on the footswitch of the Octave-X, it diminishes the overall strength of the feedback being sent to the guitar from the Sustainiac pedal, varying with what note and harmonic-overtones are feeding-back and sustaining. Some notes immediately fade out when the Oct-X is switched on, others merely drop a little, but none are UN-affected by it.

 

Switch the Octave-X off, and the feedback-signal from the Sustainiac pedal to the transducer on the guitar's headstock INSTANTLY goes back to full-strength.

 

Why would this be happening? Some sort of impedance weirdness?

 

Is it something that can be fixed?

 

I would need to see the hookup for myself on a bench.

 

 

[myles_rose]

Hi Myles:

 

I have a couple of questions regarding amp wattage. I am trying to educate myself regarding amps. When I was singing in bands back in the 80's my gutiarists usually had either 50w or 100w stacks and also a small 10-15 watt amp they used for practicing/writing but never for rehearsing or gigs because they were no way near powerfull enough. A lot of the beginner/practice combo amps are rated 10w-15w-25w and it looks like the cost is somewhat determined by how powerful they are but for the most part they seem to fall in the $100-$150 range.

 

I was doing some comparison and looked at Fender Champs, which I remember being used by a lot of guys in the 60's & 70's for studio work anyway, not sure if they were used on stage. They run somwhere in the $300-$400 range and I was surprised to find out that they are 15 watts.

 

These are probably a silly questions, but here goes:

Are amps like the Fender Champ strictly studio amps only that would have to be run through a PA if used live and the cost difference due to the quality of the compnents and sound?

 

Is there a difference in power between solid state and tube amps of the same wattage rating? Also, is there a difference in volume due to how many speakers the head is driving so that a more wattage is needed to achieve the same amount of volume with a full stack vs a half stack vs a combo?(I remember some guys opting for 50w over 100w because they got more distortion/crunch at the same volume)

 

Thanks!

 

Please refer to my website. There are pieces of writing on amp wattage such as 50 vs 100 watt articles, amps for recording, recording techniques etc.

 

A lot of time has been spent over the years writing these things up and many of these pieces have been published in books such as the GT Tube Amp Book and others. The reason I originally created the website was so it would be a source of information and I would not have to write it all again and again.

 

Hope you understand my reluctance to write pages here.

 

 

 

 

[picker]

Very similar to a 6V6 but a bit less power ... sound a bit different ...No reason to use in a 6V6 equipped amp.

 

Would they lower the output of a 6V6 equipped amp noticeably without completely ganking the tone, or screwing up the amp?

[myles_rose]

Very similar to a 6V6 but a bit less power ... sound a bit different ...No reason to use in a 6V6 equipped amp.

 

Would they lower the output of a 6V6 equipped amp noticeably without completely ganking the tone, or screwing up the amp?

 

Do not use 6V6s in 6L6 amps is a good general rule to follow.

[Dave da Dude]

Myles, back to the Epi Galaxie 10 that I bought back in the early fall. I did switch the PreAmp tube from a 12AV7 to the 12AY7 that you recommended, a NOS JAN Tungstol from 1961 that I found locally. Tremendous improvement. Thanks!

 

The Power Tube is a 6L6 and had been re-tubed to a new RCA 6L6. I was just surfing around and looked at GT Tubes where I saw they listed 6V6's besides the 6L6's.

 

Would the 6V6 be a better choice for the Galaxie 10?

 

They also list three different 6V6's, the 6V6C, 6V6R and 6V6S. The descriptions are rather... terse. It seems as though they go from soft 'n bluesy to hard 'n rockin' in alphabetical order.

 

Is that right?

 

Which of those would you recommend?

 

Or, something different?

 

As usual, thank you in advance for any help at all that you can lend in my quest for... 'the tone'.

[myles_rose]

Myles, back to the Epi Galaxie 10 that I bought back in the early fall. I did switch the PreAmp tube from a 12AV7 to the 12AY7 that you recommended, a NOS JAN Tungstol from 1961 that I found locally. Tremendous improvement. Thanks!

 

The Power Tube is a 6L6 and had been re-tubed to a new RCA 6L6. I was just surfing around and looked at GT Tubes where I saw they listed 6V6's besides the 6L6's.

 

Would the 6V6 be a better choice for the Galaxie 10?

 

They also list three different 6V6's, the 6V6C, 6V6R and 6V6S. The descriptions are rather... terse. It seems as though they go from soft 'n bluesy to hard 'n rockin' in alphabetical order.

 

Is that right?

 

Which of those would you recommend?

 

Or, something different?

 

As usual, thank you in advance for any help at all that you can lend in my quest for... 'the tone'.

 

Stick with the output tube that was stock as tbe bias point on 6V6 vs 6L6 are very different

 

[Dave da Dude]

Okay. Will do Myles.

 

Thanks.

[picker]

Do not use 6V6s in 6L6 amps is a good general rule to follow.

 

Does the same rule apply to 6K6s in 6V6 amps?

[myles_rose]

Do not use 6V6s in 6L6 amps is a good general rule to follow.

 

Does the same rule apply to 6K6s in 6V6 amps?

 

The 6K6 is better in amps that were designed around this tube or older Fender stand alone reverb units. It generally expects much lower plate and screen voltages than a 6V6 and is not as powerful.

 

6K6

 

Class A Amplifier

Plate Voltage ................................. 250 V

Grid No. 2 Voltage ............................ 250 V

Grid No. 1 Voltage ............................ -18 V

Grid No. 1 Voltage Derived from Cathode Bias Resistor ....................... 480 Ω

Peak Grid No. 1 Voltage........................ 18 V

Amplification Factor .......................... 150

Plate Resistance (approx) ..................... 68K Ω

Transconductance .............................. 2200 µ

Plate Current ................................. 32 mA

Grid No. 2 Current ............................ 5.5 mA

Load Resistance ............................... 7.6K Ω

Power Output (approx) ......................... 3.4 W

Total Harmonic Distortion ..................... 10 %

 

 

 

 

 

 

[RocketRick]

Myles,

 

I plan to do a small mod on my Mesa Mark IIc+. I have two questions;

 

I will solder a piece of wire to connect pins 1 & 8 on the outside output tubes sos I can use EL34's in the 2-outside tubes.

 

1. Do you see any probs in doing this?

 

I've seen your comments and insights into many different tubes.

 

2. Can you make any recs for diff tubes for me to try in the preamp and the output sections?

 

thanks

 

rick

[myles_rose]

Myles,

 

I plan to do a small mod on my Mesa Mark IIc+. I have two questions;

 

I will solder a piece of wire to connect pins 1 & 8 on the outside output tubes sos I can use EL34's in the 2-outside tubes.

 

1. Do you see any probs in doing this?

 

I've seen your comments and insights into many different tubes.

 

2. Can you make any recs for diff tubes for me to try in the preamp and the output sections?

 

thanks

 

rick

 

Rick,

 

I would not use EL34's in the amp for two reasons .... the output transformer is not a match for EL34s and the screen resistors may not be 1K ohm 5 watt resistors as would be best used.

 

On preamp tubes, this is really a personal taste issue..

 

[RocketRick]

Thanks Myles.

 

Now I'm not saying your wrong but I did get different opinions from several users and Mike Bendinelli.

 

I talked to Mike Bendinelli, who help build and test the amp in 1984. He said it was just fine to do the mod and use the El34's. He also said some of the vintage Sylvania and GE tubes already has those pins connected so I wldn't have to do the mod but I can't find any yet.

 

Anyways, I'm inclined to do the simple mod and try it out but it never hurts to get another opinion.

 

[myles_rose]

Thanks Myles.

 

Now I'm not saying your wrong but I did get different opinions from several users and Mike Bendinelli.

 

I talked to Mike Bendinelli, who help build and test the amp in 1984. He said it was just fine to do the mod and use the El34's. He also said some of the vintage Sylvania and GE tubes already has those pins connected so I wldn't have to do the mod but I can't find any yet.

 

Anyways, I'm inclined to do the simple mod and try it out but it never hurts to get another opinion.

 

 

 

If the screen resistors are 5 watters rather than 470 ohm 3 watters then I'd go ahead and try it.... if you like it then thats all that matters.

 

[RocketRick]

OK thanks a heap

[Caevan O’Shite]

Hey, Myles-

 

If two of the tubes in a matched-quartet of EL84's in a Vox AC30TBX go red-plate, yet the other two seem fine-

 

What would be the suspected causes?

 

What should be looked for and checked in the amp afterwards, when replacing the whole quartet?

[myles_rose]

Hey, Myles-

 

If two of the tubes in a matched-quartet of EL84's in a Vox AC30TBX go red-plate, yet the other two seem fine-

 

What would be the suspected causes?

 

What should be looked for and checked in the amp afterwards, when replacing the whole quartet?

 

The first thing I would suspect is one tube was damaged in shipping especially if the old quad did not do that.

 

 

 

 

[Caevan O’Shite]

Cool, thanks, Myles.

 

By the way, check the ooold thread of yours that I bumped up on the forum- "The best Fender 60's creme Twin that I have ever seen"- I gotta know more!

[myles_rose]

Cool, thanks, Myles.

 

By the way, check the ooold thread of yours that I bumped up on the forum- "The best Fender 60's creme Twin that I have ever seen"- I gotta know more!

 

That was a long time ago ... the amp went to Chris Issak I believe.

 

 

[Caevan O’Shite]

Damn, Sam!

 

So, waddya think it'd take to cop its basic groove- build a "blonde" 4x6L6 Twin Amp clone with a "Presence"-circuit and an extra beefy oversized output-transformer?

[myles_rose]

Damn, Sam!

 

So, waddya think it'd take to cop its basic groove- build a "blonde" 4x6L6 Twin Amp clone with a "Presence"-circuit and an extra beefy oversized output-transformer?

 

Talk to David Hayes .... he is on my facebook page and myspace page in my top friends on that page. He could build a real one.