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bad tubes?

Discussion in 'Amps and Cabs [BG]' started by FunkThumb, Dec 29, 2001.


  1. alrighty...
    my tube amp is having some problems, on it it has the kind of volume control where when you turn the vulume up it so turns on (no seperate on/off switch) and the problem is is there is almost no audible difference between the volume control at 1/4 and the volume at full...this by the way is not very loud. i've heard that it may be a pre-amp tube problem, and if you think it is please tell me which tube you think is the problem...my amplifier has one 5y3, one 6V6, one 12ax7, and two 6av6's

    thank you, and i would like to say that this is the most friendly forum site on the web IMO.
     
  2. well i like to DIY...and i know how to unplug things...so what would you sugest then... bad caps?, bad pots?
     
  3. rwagne2

    rwagne2

    Aug 2, 2001
    is that an old phonograph amp?

    with that tube complement, the only possible configuration is it being a 5 watt (if even that much) class A amp... which is not exactly loud, or suited to being a bass amp. The output transformer is probably what is mostly holding you back.

    That thing might really scream for a guitar, but I don't think its too suited for bass.

    That being said, its probably just needs a cap job.
    The tubes are probably fine.

    btw the 12ax7 is the preamp tube
     
  4. hammong

    hammong

    Apr 11, 2001
    Sparks, Maryland
    I have to agree with rwange2 - the tubes you listed don't strike me as being a high-power application. What brand and model of amp are you working with? It sounds like an old Vox electric guitar amp, and a practice-sized amp at that.

    Can you hear more of a difference at high or mid-range frequencies than you at low frequencies when you adjust the volume? Bad caps make of a difference at lower frequencies than high frequencies because of the current draw differences.

    Greg
     
  5. Ha...yeah it likely is!

    well thankfully i got this for what works out to be about 50 bucks american...so whoopidee about the lost cash... it is made by "ford":confused: i have no idea who the hell that is but any way i'll give ya some details...it is a 2 by 12" combo amp with one eq knob (a bass and treble blend knob, passive by the way) and a tremolo control (with footswitch plug)...i was guessing it was fairly old...maybe something like 70's? i don't really know... On the front, instead of having a grill or that weird mesh that is on fender amps, this amp has a blue/grey velvet like material.

    thank you for the suggestions, any other info would be good.:D