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Re: AMP FREAKS OUT [message #9531 is a reply to message #9529] Wed, 08 February 2006 09:01 Go to previous messageGo to next message
Wayne Parham is currently offline  Wayne Parham
Messages: 18271
Registered: January 2001
Illuminati (33rd Degree)

Wow, that's interesting. Not unusual, but interesting. I've noticed that in other equipment too. An example is the Bottlehead Paramour pops and crackles like a Geiger counter about half the time when used with the Valve Art 2A3 shipped with the kit. But Electro-Harmonix and other tubes are noise-free.


Re: AMP FREAKS OUT [message #9534 is a reply to message #9529] Thu, 09 February 2006 12:18 Go to previous messageGo to next message
Aki is currently offline  Aki
Messages: 36
Registered: May 2009
Baron
Well, since my alter ego is a wailing blues guitar player, let me see if I can jump in and help on this one.

It's difficult to tell remotely, but it does sounds like you ran into a bad tube. But since the tube worked for some time, it's somewhat possible that somehow your replacement tube didn't make good contact in the socket or some other odd thing went wrong.

As for output tube re-bias, you don't need to do it unless you change the output tubes so you are OK there.

You should be able to get a replacement 12AX7 at the store where you got it from. Typical guitar stores wouldn't have the equipment to test tubes (a number of them orders from people like me), and big franchises, as you know, couldn't care less. But if it's a friendly shop, you might be able to get them to try the replacement tube in their house amp for a while. At least that'll give you some level of comfort.

If this problem does happen again with another replacement, I'd take the amp into a tech though.

Aki

Re: AMP FREAKS OUT [message #9535 is a reply to message #9529] Thu, 09 February 2006 19:08 Go to previous messageGo to next message
Shane is currently offline  Shane
Messages: 1109
Registered: May 2009
Illuminati (3rd Degree)
I agree with Aki. You probably got a bad tube. I don't know where you live, but here in Amarillo we have a smaller guitar shop that has a tube tech. They'll test your new tubes for you before you leave the store to check for matching, etc... if you ask. You might check around where you are to see if there is a store that has a tube tech in house.

Re: AMP FREAKS OUT [message #9536 is a reply to message #9535] Thu, 09 February 2006 23:46 Go to previous messageGo to next message
blades976 is currently offline  blades976
Messages: 20
Registered: May 2009
Chancellor
It's no big deal as long as the amp didn't fry. $20 is a cheap lesson to learn all things considered. I'll be ordering a tube from Aki on payday and hope to have better results from somebody who specializes in tubes.

It’s amazing the difference the tubes make though. When the amp freaked out I plugged in the bass via the effect peddle to the board. Nice and clean but no balls. I'm starting to see why tube heads are so obsessed with the sound of tube amps.

John

Re: AMP FREAKS OUT [message #9537 is a reply to message #9529] Thu, 09 February 2006 12:18 Go to previous messageGo to next message
Aki is currently offline  Aki
Messages: 36
Registered: May 2009
Baron
Well, since my alter ego is a wailing blues guitar player, let me see if I can jump in and help on this one.

It's difficult to tell remotely, but it does sounds like you ran into a bad tube. But since the tube worked for some time, it's somewhat possible that somehow your replacement tube didn't make good contact in the socket or some other odd thing went wrong.

As for output tube re-bias, you don't need to do it unless you change the output tubes so you are OK there.

You should be able to get a replacement 12AX7 at the store where you got it from. Typical guitar stores wouldn't have the equipment to test tubes (a number of them orders from people like me), and big franchises, as you know, couldn't care less. But if it's a friendly shop, you might be able to get them to try the replacement tube in their house amp for a while. At least that'll give you some level of comfort.

If this problem does happen again with another replacement, I'd take the amp into a tech though.

Aki

Re: AMP FREAKS OUT [message #9538 is a reply to message #9534] Fri, 10 February 2006 00:02 Go to previous messageGo to next message
blades976 is currently offline  blades976
Messages: 20
Registered: May 2009
Chancellor
I think the tube had good contact. When I replaced the tube I also had to undo and re-attach an "arm" that put downward pressure on the top of the tube effectively holding it in place.

The amp is solid state; the only tube in it is the one pre amp tube, hence my assumption to re-bias it.

I'm a bit sketchy on the idea of going back to the shop. Its one of those guitar shops with used gear that’s WAY too old and beat up. I'm willing to cut my losses at $20 for the tube and be grateful the amp didn't permanently roast. I'll try order another replacement from a specialist (I’ve heard of this company named BOI AudioWorks…) and not chance smoking a bass amp in order to save $2-3. I have my eye on the 12AX7EH-GOLD you stock. I'm hoping it will fill the bill. Clean is what I am looking for.

John



Re: AMP FREAKS OUT [message #9547 is a reply to message #9536] Sun, 12 February 2006 18:29 Go to previous messageGo to next message
Shane is currently offline  Shane
Messages: 1109
Registered: May 2009
Illuminati (3rd Degree)
Hope everything is OK with the amp. I'm sure it will be.

I know what you mean about tube gitfiddle amps. I used SS for a while and then bought my first tube amp when I started playing gigs 6 years ago--a Peavey 5150 combo. I still have that amp, but haven't used it much cause since we moved to TX. I usually use an old early 70's Fender Vibrochamp I picked up from an 80 year old man at church for $25. Best buy I ever made. Couldn't get him to part with his old Bandmaster head or Leslie speaker.

12AX7EH-GOLD goes in tomorrow [message #9549 is a reply to message #9534] Mon, 13 February 2006 23:06 Go to previous messageGo to next message
blades976 is currently offline  blades976
Messages: 20
Registered: May 2009
Chancellor
I got my tube today (Very quick delivery), I'll be putting it in the bass amp tomorrow. It is a nice looking piece of work. I sure hope the amp likes this one...

Re: 12AX7EH-GOLD [message #9558 is a reply to message #9549] Thu, 16 February 2006 13:48 Go to previous messageGo to next message
blades976 is currently offline  blades976
Messages: 20
Registered: May 2009
Chancellor
The new tube is in and everything is working out great so far. The hiss is reduced although not gone (to be expected from tubes anyway) and the amp hasn't pitched a fit. No critical listening done yet though to compare the new tube to the old as last night's practice was kind of nuts with an extra guitarist, a drum machine, and a keyboard along with the regular band. Translation, it was loud as hell.

Hopefully next practice will be a bit more subdued and I can get some critical listening done with the new tube sound.

John

Re: 12AX7EH-GOLD Good to hear it works. [message #9560 is a reply to message #9558] Thu, 16 February 2006 20:08 Go to previous messageGo to previous message
Shane is currently offline  Shane
Messages: 1109
Registered: May 2009
Illuminati (3rd Degree)
Glad to hear that the new tube is working for you at least from the get go. I've heard tube amps that didn't hiss at all, though. But you should hear my 5150. That thing has so much gain that when you turn it up the hiss will knock you down. When we were gigging it was almost mandatory to have a noise gate on the thing.

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