Feel free to ask Myles

[myles_rose]

Bill ... what kind of amp? If you are not up on amp repair or not comfortable with lethal voltages take it to a tech.

[janealex]

I have got new base guitar few months ago, but after 5 months its changing sound automatically. Some experts are saying that its not repairable can you please tell me what is now happen in my favor.

[Caevan O’Shite]

janealex- do you mean that the bass is inconsistently changing pickup-selection or making weird noises, or do you mean that the bass amplifier is making strange, inconsistent sounds?

[myles_rose]

I need a little more information myself :-)

 

Could be anything from broken neck to amp to use of alchol or drugs to ....

[BD7]

Hey Miles, it's been a few months since our last contact and I did put the Brimar in V2 and it's fat city with the tele in V1. What would you recommend in vintage/NOS for the PI position? I have heard everything from it's not that important to you need long plate, high gain, etc..

thx

[myles_rose]

For the PI position I prefer long plates. In general, they take a bit longer to compress. Just my personal taste.

 

You do not have to go the NOS route as long as your vendor can test to assure proper plate current. You do not want a weak tube here in most cases.

 

If you want the amp to break up faster / earlier, then a weak phase inverter is an option as it will take a dive sooner.

 

In the case of a 12AX7, the spec for plate current is 1.2mA. Most tubes today are lower (unless they are off in plate resistance which will make the plate current high but then the gain is low and the tube may crosstalk).

 

I prefer plate current output to be 1.1-1.4mA on a long plate tube like a Sovtek 12AX7LPS. These are pretty inexpensive.

 

Keep in mind that is my personal generic preference.

 

The JJ 803S is a long plate that some folks like a lot.

 

The Tung Sol reissue is a short plate but works quite nicely in the phase inverter position. 65 Amps uses those a lot so I see many come across my bench when they ask me to test some tubes for them.

 

Some good vendors that can test and assure a balance between the A and B sides (that is important to me as a side note) are:

 

www.kcanostubes.com

www.dougstubes.com

www.tubedepot.com

 

There are other good vendors out there but I know the work of the above folks.

 

With a Tele you may want the more articulate nature of the Tung Sol Reissue.

 

In the end it is personal taste.

 

 

 

 

 

 

[BD7]

Great info as always. Thank you sir!

[Junior 1]

Hi Myles,

I hope all is well. I've been looking at a few Boss pedals and in all their info they state that any power supply other than a boss one could damage the pedal. Is this BS or do you really need a Boss power supply.

Thanks

Anthony

[myles_rose]

Anthony - just have the right voltage and current capacity, observe the proper polarity and all is fine.

 

Think of how many pedalboards do you see out there with after market power supplies. They work great. Tons of them.

 

 

[Electric Biscuit]

Hey Miles,

 

Do you know anything about making a low-budget spring reverb tank to run through an effects loops? I have heard something about being able to adapt a stock Fender replacement tank; how much trouble/work would this be, if it is even possible.

 

-Colin

[Junior 1]

Thanks for the reply to a dumb question, but now, it's gospel because Myles told me!Have a great day.

Anthony

[myles_rose]

Colin,

 

I suppose you could lash up something that made sound come out the other end but reverb circuits use transformers, have higher drive current requirements that a simple effects loop can provide and there are impedance issues that need to be taken into the design.

 

Stick some sort of reverb pedal in your effects loop and velcro it inside the cab or head. It will work better, sound better and not impact other aspects of your amp and tone.

 

[Caevan O’Shite]

Hey, Myles- am I correct in saying the following?

 

"on MOST guitar amps, the treble, middle and bass controls only attenuate frequencies; they do NOT "boost" anything, unless they are specifically active-EQ circuit designs made for both boost AND cut."

 

 

I was replying in response to the following:

 

__________________________________________________________________

"Tone Controls

Magnetic guitar pickups are inductive, and require compensation, although this opportunity is also used for tone enhancement, not just correction. Without compensation, they have a strong low middle emphasis and little high frequency response - overall a very muddy and muffled sound. This is why typical hi-fi Baxandall treble & bass controls are unsuitable.

 

To hear the natural sound of a pickup, use a typical guitar amp with the middle set to full, and bass and treble on zero. This is actually sets a flat response in the amp (see below), and I expect you will hear a muffled and muddy sound. And that's the whole point of these tone controls providing compensation for the natural sound of a pickup - the middle control simply boosts the pickup's normal middley sound. The treble and bass controls do the opposite - they boost higher and lower frequency levels, leaving a notch in-between for middle cut (see the Fender/Marshall comparison below). So with typical settings of a bit of bass, middle and treble, the overall tone equalisation complements the natural pickup sound for a balanced response of lows, mids and highs.

 

 

Full middle boost with no bass or treble actually gives a near-flat frequency response, allowing you to hear the natural sound of your pickups.

 

Here are circuit diagrams of typical Fender and Marshall tone controls. They both meet the criteria of compensating for pickups' low-middle emphasis, as well as providing a useful range of tone adjustment.

 

 

 

The Fender and Marshall circuits are each tailored to suit their own styles, which are quite different. Although a generalisation, Fender's market and power output stage are geared towards provided clean and chunky tones at clean and early-overdrive levels. Marshall amps are best at low-middle and crunchy rock tones, played at medium to high overdrive levels."

__________________________________________________________________

[myles_rose]

You are correct. I could get more complex but your explanation is more effective and to the point than mine probably would be :-)

 

[Caevan O’Shite]

Thanks, Myles!

[Zephyr]

Hey Myles, for new production EL84s, are there any that are sturdier, and/or capable of running at higher voltages than the rest? I'm basically looking for one that can beef up an Epi Valve Junior and provide maximum headroom.

 

Thanks!

[myles_rose]

Hey Myles, for new production EL84s, are there any that are sturdier, and/or capable of running at higher voltages than the rest? I'm basically looking for one that can beef up an Epi Valve Junior and provide maximum headroom.

 

Thanks!

 

The JJ EL84S is still the best on the market. It is stronger, lasts longer and traces smoother than any of the other current EL84 tubes.

 

If you want something smooth but strong, go here... call them, ask for Marty, tell Marty you talked to me and you need a duet of 40-44 tubes according to Myles. He will know what you mean. These are in the same range as the tubes I send to Chad for Brad Paisley and are proper spec but a bit on the cleaner side.

 

Oops .... forgot the link - http://www.arselectronics.com/

[Zephyr]

Awesome, thanks Myles.

 

http://www.fadzter.com/smilies/beerchug.gif

[myles_rose]

You are quite welcome

[tarkus]

hello myles - I'm having Amplifier problems:

 

the amp: Ampeg BA210SP Digital (combo amp) - about 9 years old - warrantee expired.

It has built in effects and I'll use them from time to time.

 

the problem:

I'm getting signal interference/distortion - it sounds like "hiss-buzz" - it doesn't cancel the signal, but it is audible and enough to drive you batty.

The other fun thing - this interference occurs in patterns - approximately 5 second intervals for about 30 seconds.

 

it is not continuous and it seems like it may have something to do with FX selector or the FX componant.

 

I've noticed the problem occurring after selecting particular FX and then returning to dry signal.

 

I experimented with different cables and wireless - no luck - I think it's internal.

 

it only occurs at the rehearsal space and at the last gig I played - could be faulty ground / florescent lighting, neon etc...

 

at home, I do not have this problem, but I do not practice at high volume or have the amp "on" for more than 1 hour.

 

I did leave it on for about 3 hours at home with the input volume and level at concert volume.

 

Again - at home I do not have any problems.

 

What would be the best method to trouble-shoot this?

 

Thanks

 

 

 

[myles_rose]

Sounds as if your rehersal space has a ground issue with their power. Try a ground lift.

[tarkus]

thanks myles!

[myles_rose]

You are quite welcome

[Caevan O’Shite]

Myles-

 

What might be some of your recommendations for an amp-shopper, willing to spend in the range of $3k or so, looking for a "do it all" channel-switching amp with three or four channels? (Three channels minimum.)

 

He wants "to be able to play everything from the blues to hillbilly country to classic rock to mid-scooped metal."

 

Variable power is a plus for him, too, whether different watt settings, "Power Scaling", "Master Voltage", etc. He will be using the amp at home, in the garage, AND, in time, with bands...

 

Any promising candidates in the up to $3k +, multi-channel, "do it all", chunky/scooped metal-capable tube-amp category?!

 

[myles_rose]

I don't think there is such a thing as a multi channel do it all amp at any price.

 

I think you could cover more ground more cheaply and more reliably with a good clean amp and a small pedal board.

[Caevan O’Shite]

I don't think there is such a thing as a multi channel do it all amp at any price.

 

I think you could cover more ground more cheaply and more reliably with a good clean amp and a small pedal board.

 

Thanks, Myles!

 

I kinda thought more or less the same, myself; I figure that, there're versatile amps that are good for almost everything BUT mo' modernish "mid-scooped metal";

 

and then there're amps that are good at more extreme modern "mid-scooped metal", that are too hard, tight, stiff, for nearly "everything else".

 

MAYBE "almost everything else" and '70s to early/mid '80s "Metal" can be reasonably done by a good channel-switcher like a Fuchs, Rivera, MESA/Boogie, etc., especially by a player with a good "touch" and grasp of "playing the amp";

 

but there seems to be a dividing-line between those that can reasonably do "Country/Blues/Classic-Rock/etc." and those that can convincingly do heavier, chunkier, more percussive mid-scooped "Modern Metal".

[myles_rose]

Most of the players I know have at least a couple of amps. In my day (the old days) one might have a Fender blackface something and a Marshall something.

[Caevan O’Shite]

Most of the players I know have at least a couple of amps. In my day (the old days) one might have a Fender blackface something and a Marshall something.

 

In a way, that's sort of still the recipe!

[soundbeing]

hey Myles,

 

i have a homemade tube amp from the late 40's or 50's. its an old Webcore radio converted in to a guitar amplifier. pretty amazing little devil. recently, the speaker has separated from the voice coil. this old speaker has very little detail regarding its make and model. i was able to find out that it is a vintage Magnavox speaker, but unable to find out the Ohms. i'm searching for a replacement speaker and have chosen a pretty sweet Jensen C8R that i think will do well. i'm just not sure whether to get the 8 Ohm or the 4 Ohm model. what do you think? will it cause any problems if the amp is say 4 ohms and the speaker is 8 ohms, or vice versa?

 

thanks!

[myles_rose]

If the voice coil is intact meter it. a 8 ohm speaker will read a bit less than 8 ohms and a 4 ohm speaker a bit less than 4.

 

You can have the speaker reconed, there are many good folks that do this.

 

Stick with the proper impedance. You can have a tech measure the output transformer if you are not sure.

 

If it is 8 ohms and you use a 4 ohm speaker you can damage the output transformer.