Feel free to ask Myles

[Salad Days]

Looks like i'll go with the 6L6CHP's then!

Thanks myles.

I appreciate the advice.

[myles_rose]

Looks like i'll go with the 6L6CHP's then!

Thanks myles.

I appreciate the advice.

 

You are quite welcome.

 

The other great 6L6 is the winged C (real) Svetlana.

 

you can get either of them from Mike at KCA .... www.kcanostubes.com

 

or

 

www.tubesandmore.com

 

They are both great vendors and discount nicely.

 

 

[Salad Days]

Hi again Myles.

 

I have another question. I hope you dont mind.

 

So I got a set of matched JJ 6l6gc's. I looked around for the ones you mentioned but they were a fair bit more expensive than the JJ's so I just opted to go for them.

 

So they arrived this morning and after trying them out I'v noticed something...

 

Whenever I play a note at decent volume they give a high pitched rattle sound that sort of squeaks. The more I push the amp the worse it gets.

This only happens for a second as soon as the note is played but after all the trouble i'v been through with my amp its got me concerned.

 

I did wonder if it was perhaps that the valves were not broken in yet or perhaps i'v biased them too hot but I thought it best to ask a trusted opinion before i do anything else, just incase.

 

I am running the amp with an attenuator (tube cube) if that matters.

 

Thanks again!

Rich

[myles_rose]

Hi again Myles.

 

I have another question. I hope you dont mind.

 

So I got a set of matched JJ 6l6gc's. I looked around for the ones you mentioned but they were a fair bit more expensive than the JJ's so I just opted to go for them.

 

So they arrived this morning and after trying them out I'v noticed something...

 

Whenever I play a note at decent volume they give a high pitched rattle sound that sort of squeaks. The more I push the amp the worse it gets.

This only happens for a second as soon as the note is played but after all the trouble i'v been through with my amp its got me concerned.

 

I did wonder if it was perhaps that the valves were not broken in yet or perhaps i'v biased them too hot but I thought it best to ask a trusted opinion before i do anything else, just incase.

 

I am running the amp with an attenuator (tube cube) if that matters.

 

Thanks again!

Rich

 

One of the tubes may be physically microphonic. Pretty common ... shipping damage or handling damage.

 

What amp and what is your bias set at?

 

 

 

 

[Salad Days]

Its the marshall 1987x.

I set the bias to around 32. One at 30, one at 34.

 

If i measured the plate voltage correctly I got around 470.

[myles_rose]

Its the marshall 1987x.

I set the bias to around 32. One at 30, one at 34.

 

If i measured the plate voltage correctly I got around 470.

 

That is fine.

 

 

[Salad Days]

Ugh, its one thing after another just now...

 

I'll try and take it up with the place that sold me them although I expect they'll pass it off on the post office.

 

I wish now i'd gone through a shop rather than ebay.

 

If i cant get this resolved I think i'll just shell out that little bit more for the winged C's this time round.

 

Thanks again for the advice myles. Really.

Its much appreciated.

 

Rich W.

[myles_rose]

Ugh, its one thing after another just now...

 

I'll try and take it up with the place that sold me them although I expect they'll pass it off on the post office.

 

I wish now i'd gone through a shop rather than ebay.

 

If i cant get this resolved I think i'll just shell out that little bit more for the winged C's this time round.

 

Thanks again for the advice myles. Really.

Its much appreciated.

 

Rich W.

 

Rich,

 

On output tubes .... a few things....

 

Always have them shipped insured. This costs very little and if there are problems the post office or UPS will cover things.

 

If shipped UPS only ship 3 day express and never ground unless they are coming from the same state. This is policy on output tubes shipped from GT. They have learned over the years that there is less transfer of a package with 3 day and the damage rate is cut by more than 50% of the cases of damage.

 

 

[Dave da Dude]

Myles, in another thread a while ago, someone was asking for advice on what very small tube amp to buy etc.

 

I mentioned a Kustom 12W Practice Amp (Hybrid tube PreAmp, SS Output) and someone pointed out that did not give the desired result since the power tube distorting was the sound that was treasured.

 

I thought the PreAmp tube also lent a favorable distortion to the sound. I had (since lost... still lookin') a 1993 Randall Tube Pro II that I liked very much for tone with my Highway 1 Strat.

 

Would a Hybrid amp like that be so far off the mark? I'm trying to get started again, no guitar or amp atm and trying to keep if very cheap.

[myles_rose]

Myles, in another thread a while ago, someone was asking for advice on what very small tube amp to buy etc.

 

I mentioned a Kustom 12W Practice Amp (Hybrid tube PreAmp, SS Output) and someone pointed out that did not give the desired result since the power tube distorting was the sound that was treasured.

 

I thought the PreAmp tube also lent a favorable distortion to the sound. I had (since lost... still lookin') a 1993 Randall Tube Pro II that I liked very much for tone with my Highway 1 Strat.

 

Would a Hybrid amp like that be so far off the mark? I'm trying to get started again, no guitar or amp atm and trying to keep if very cheap.

 

Touch sensitive distortion and player interaction comes from the output stage of an amp not the gain stage. This is why lower powered tube amps are so much in favor today ... you can run them on the edge and not offend people AND use large diaphram studio mics on stage and not blow up mics where generic stuff like a Shure SM57/58 used to be used with all its compromised tone.

 

[Mike Gug]

Hey Myles! Long time no talk to! Hope all is well. Question: can I do damage to my Peavey Classic 30 if I run a 1/4 inch lead microphone cable in the "INPUT" for use as a PA (vocal SM58) during a few dozen practices? Thanks!

[myles_rose]

Hey Myles! Long time no talk to! Hope all is well. Question: can I do damage to my Peavey Classic 30 if I run a 1/4 inch lead microphone cable in the "INPUT" for use as a PA (vocal SM58) during a few dozen practices? Thanks!

 

Won't hurt a thing but it won't sound all that great as the response and EQ is not wide range in a guitar amp .... but then again, it will work as a PA of a sort.

 

 

[Dave da Dude]

Myles, still tryin' to work out how to do tube amp on a budget. I absolutely MUST have a Headphone Output.

 

The only one I can find (low power/low cost) is a Peavy ValveKing Royal 8 (8W Class A). And that may suit my needs just fine.

 

But... IF I find it won't, is there's any (easy) way to get headphones plugged into an external Spkr Out or Line Out without melting down the amp?

 

 

[myles_rose]

Myles, still tryin' to work out how to do tube amp on a budget. I absolutely MUST have a Headphone Output.

 

The only one I can find (low power/low cost) is a Peavy ValveKing Royal 8 (8W Class A). And that may suit my needs just fine.

 

But... IF I find it won't, is there's any (easy) way to get headphones plugged into an external Spkr Out or Line Out without melting down the amp?

 

 

Do NOT plug headphones into the amp via the speaker jack.

 

Look at some of the budget amps as they have headphone outs.

 

 

[Dave da Dude]

Look at some of the budget amps as they have headphone outs.

The ONLY one I can find (low power/low cost) is the Peavy ValveKing Royal 8 (8W Class A).

 

Do you know of any others? I have a thread going on this atm too.

 

Myles, as always, thanks for your help on this.

 

[myles_rose]

Look at some of the budget amps as they have headphone outs.

The ONLY one I can find (low power/low cost) is the Peavy ValveKing Royal 8 (8W Class A).

 

Do you know of any others? I have a thread going on this atm too.

 

Myles, as always, thanks for your help on this.

 

I am sure there are many but I do not keep track of this sort of thing. Go to Guitar Center as one idea.

 

 

[Dave da Dude]

Do NOT plug headphones into the amp via the speaker jack.

 

Myles, not even with this? Weber Headphone Tap and Dummy Load

[myles_rose]

Do NOT plug headphones into the amp via the speaker jack.

 

Myles, not even with this? Weber Headphone Tap and Dummy Load

 

 

That would work great.

 

 

[Dave da Dude]

Myles, no reply needed on this, just a great big thank you for your help on this. I know how busy you must be and the Forum is certainly extremely fortunate to have you as our resident amp guru.

 

May all your amps be... RAWKIN~!!

[myles_rose]

Myles, no reply needed on this, just a great big thank you for your help on this. I know how busy you must be and the Forum is certainly extremely fortunate to have you as our resident amp guru.

 

May all your amps be... RAWKIN~!!

 

Thanks for the kind words.

 

By the way, you might not know this but for folks in this forum that are ever going to be in So Cal with their amp(s) I am happy to go over them, check them out, clean and lube the pots and sockets if necessary, check and adjust the bias if needed at no charge.

 

Myles

 

[BoyoBoyle]

Hey Myles, I heard that you know a lot about tube amps, so if you could help me out anyway i would much appreciate it.

 

Im a college student trying to find myself a guitar amp, and i figured the cheapest way to do it would be to build my own amp.

 

Now, I just took a class on electrical wiring, and have made a few projects which involve nearly over 50 some components and involve some construction, so i feel i got an allright grasp on wiring and feel i may be ready to build myself an amp. I am not good at understanding a schematic sheet, but if i have a component list and a layout sheet, then chances are im good on it. Some instruction helps too. And after looking at some of these projects, they really don't seem too difficult.

 

First, i want a tube amp, luckily almost all of the kits i found where tube and all i really need is about 5watts of tube power and I'm good, no more than 10watts (i'l take 10 though if it's cheap enough.) After looking around and reading reviews, i found out about the AX84 P1 model. It seems simple and would be good for a beginner like myself and has 5 watts of tube power, which is perfect, and its an allright price for about $200. Here is the link I found of the actual kit and where i am looking to buy it from.

 

http://www.ax84.com/p1.html thats the site for the P1, and there are many other sites but this is the one from the AX84 site.

 

http://shop.dobermanamps.com/product-p/kit-p1.htm this is the site where i will probably be purchasing it. I will buy the precut chassis, but I'm not sure if i need any "octal tube upgrades". If i dont need them, i won't buy them.

 

As for a speaker I was looking at this one

http://www.musiciansfriend.com/product/Celestion-V1260-Silver-Series-12-Speaker?sku=660236

I would rather have a 12" than two 10's, but i would like your opinion on that, let me know if it's crucial.

 

As for a speaker cabinet, i am not too worried at this moment (should I?) I am skilled in woodworking and am sure i would be able to construct one. Also, do i really need a cabinet for the head, other than to protect it?

 

Well, thats what I'm looking at getting. Now, if i buy that kit and the speaker, is that all i would need to purchase to get the amp working? what else do i have to purchase? I already have a soldering iron, heat sinks, solder, and would be able to get wire.

 

I heard you're the best so i hope you can help me out on this, as much advice you can provide would help me out so much.

Thanks

[myles_rose]

Hey Myles, I heard that you know a lot about tube amps, so if you could help me out anyway i would much appreciate it.

 

Im a college student trying to find myself a guitar amp, and i figured the cheapest way to do it would be to build my own amp.

 

Now, I just took a class on electrical wiring, and have made a few projects which involve nearly over 50 some components and involve some construction, so i feel i got an allright grasp on wiring and feel i may be ready to build myself an amp. I am not good at understanding a schematic sheet, but if i have a component list and a layout sheet, then chances are im good on it. Some instruction helps too. And after looking at some of these projects, they really don't seem too difficult.

 

First, i want a tube amp, luckily almost all of the kits i found where tube and all i really need is about 5watts of tube power and I'm good, no more than 10watts (i'l take 10 though if it's cheap enough.) After looking around and reading reviews, i found out about the AX84 P1 model. It seems simple and would be good for a beginner like myself and has 5 watts of tube power, which is perfect, and its an allright price for about $200. Here is the link I found of the actual kit and where i am looking to buy it from.

 

http://www.ax84.com/p1.html thats the site for the P1, and there are many other sites but this is the one from the AX84 site.

 

http://shop.dobermanamps.com/product-p/kit-p1.htm this is the site where i will probably be purchasing it. I will buy the precut chassis, but I'm not sure if i need any "octal tube upgrades". If i dont need them, i won't buy them.

 

As for a speaker I was looking at this one

http://www.musiciansfriend.com/product/Celestion-V1260-Silver-Series-12-Speaker?sku=660236

I would rather have a 12" than two 10's, but i would like your opinion on that, let me know if it's crucial.

 

As for a speaker cabinet, i am not too worried at this moment (should I?) I am skilled in woodworking and am sure i would be able to construct one. Also, do i really need a cabinet for the head, other than to protect it?

 

Well, thats what I'm looking at getting. Now, if i buy that kit and the speaker, is that all i would need to purchase to get the amp working? what else do i have to purchase? I already have a soldering iron, heat sinks, solder, and would be able to get wire.

 

I heard you're the best so i hope you can help me out on this, as much advice you can provide would help me out so much.

Thanks

 

The AX84 is a cool project and yields a nice amp and is a great starting point.

 

 

[Tone Taster]

Miles, I want to convert the power section of a Red Bear MKE 60 from two Sovtek 5881's which came stock, to 2 6550's

 

How do I know if the transformer can handle that kind of draw?

 

The circuit is very similair to a 2204 circuit and PTP

[myles_rose]

Miles, I want to convert the power section of a Red Bear MKE 60 from two Sovtek 5881's which came stock, to 2 6550's

 

How do I know if the transformer can handle that kind of draw?

 

The circuit is very similair to a 2204 circuit and PTP

 

You need to make sure the screen resistors are 5 watt 1K ohm and you may have to alter the bias supply as you will need about -60 volts or so to keep the tubes at the proper bias level. You would adjust to 45mA or so.

 

 

[Zephyr]

Myles,

 

I believe that my Deluxe Reverb is overheating, even for 30 minutes at 20% volume, the back is piping hot when I go to feel it. I replaced every tube less than a month ago and I don't want them to be short-lived.

 

Do you know of any internal components that could be responsible for excessive heat if they are loose or broken?

[myles_rose]

Myles,

 

I believe that my Deluxe Reverb is overheating, even for 30 minutes at 20% volume, the back is piping hot when I go to feel it. I replaced every tube less than a month ago and I don't want them to be short-lived.

 

Do you know of any internal components that could be responsible for excessive heat if they are loose or broken?

 

 

What is your bias set to in milliamps?

 

 

[Zephyr]

Myles,

 

I believe that my Deluxe Reverb is overheating, even for 30 minutes at 20% volume, the back is piping hot when I go to feel it. I replaced every tube less than a month ago and I don't want them to be short-lived.

 

Do you know of any internal components that could be responsible for excessive heat if they are loose or broken?

 

 

What is your bias set to in milliamps?

 

 

The set I have in there has a mixed bias as I was not able to get a matched pair. The tech I went to said he had to put one higher than the other and it is operating at bench specs. As for specifics I do not know.

 

Normally I would have considered this to be the problem, except I had the problem when it was stock, I just never really thought anything of it before until now.

[myles_rose]

Myles,

 

I believe that my Deluxe Reverb is overheating, even for 30 minutes at 20% volume, the back is piping hot when I go to feel it. I replaced every tube less than a month ago and I don't want them to be short-lived.

 

Do you know of any internal components that could be responsible for excessive heat if they are loose or broken?

 

 

What is your bias set to in milliamps?

 

 

The set I have in there has a mixed bias as I was not able to get a matched pair. The tech I went to said he had to put one higher than the other and it is operating at bench specs. As for specifics I do not know.

 

Normally I would have considered this to be the problem, except I had the problem when it was stock, I just never really thought anything of it before until now.

 

 

Most of the stock amps are underbiased and run too hot so having this issue stock is no surprise to me.

 

You might want to find a new tech. Anybody that would install a mismatched set of output tubes and bring on short life, no sustain, increased hum and the other problems with an unmatched output section would not be somebody I would take an amp to.

 

So the question still remains ... what is the bias set to?

 

and .....

 

Get a set of matched 6V6's in the amp before the heat destroys the caps and cooks the resistors around the tube socket area. Hopefully your screen resistors are not too far gone from drifting if not damaged at this point.

 

If you want to cut corners and settle for poor tone out of such a nice amp then you may want to sell it and go with a nice solid state amp with little maintenance.

 

 

 

 

[Zephyr]

Very well, I will call him and get that info.

 

I am sorry, but I had a mental lapse earlier, they are a matched pair with a matching current of 22. I hope there is minimal to no damage done, but stupidity has gotten the better of me.

 

In the meantime, I'll give Mike a shout at KCA and ask him about a full diagnostic in case of the worst.

 

And as always Myles, thanks for your time and sage advice.

[myles_rose]

Very well, I will call him and get that info.

 

I am sorry, but I had a mental lapse earlier, they are a matched pair with a matching current of 22. I hope there is minimal to no damage done, but stupidity has gotten the better of me.

 

In the meantime, I'll give Mike a shout at KCA and ask him about a full diagnostic in case of the worst.

 

And as always Myles, thanks for your time and sage advice.

 

 

Mike at KCA is somebody you can trust and he does things right.