Search found 4580 matches

by Stevem
Sun May 05, 2024 11:57 am
Forum: Technical Discussion
Topic: Light bulb limiter tured bright at power on
Replies: 6
Views: 176

Re: Light bulb limiter tured bright at power on

Yes. With too high a wattage limiter bulb a SS amp may not turn on / power up enough to even idle.
Many times when the voltage is too low all you will hear out of the speaker is hum which might lead you to think that the amp has a problem when it does not.
by Stevem
Sun May 05, 2024 11:52 am
Forum: Technical Discussion
Topic: HILGEN BASSO 2591 Bass Amp Help Needed....
Replies: 3
Views: 67

Re: HILGEN BASSO 2591 Bass Amp Help Needed....

If the 2nd 12 ax7 where missing then the amp would not play. V2A is the mixer for both channels and V2A is the phase splitter to drive the power tubes. In terms of any amp with just a tone control all it does is cut back the highs when turned down . The level of bass produced will only change with h...
by Stevem
Sat May 04, 2024 5:36 pm
Forum: Technical Discussion
Topic: Light bulb limiter tured bright at power on
Replies: 6
Views: 176

Re: Light bulb limiter tured bright at power on

The turn on current surge is much higher in a tube amp when the heaters are warming up then even what you would see with a 200 watt rms solid state amp getting powered up.
by Stevem
Fri May 03, 2024 10:20 am
Forum: Technical Discussion
Topic: JTM45 Build, looks alive but no sound,
Replies: 6
Views: 195

Re: JTM45 Build, looks alive but no sound,

This might help.
by Stevem
Thu May 02, 2024 11:42 pm
Forum: Technical Discussion
Topic: Tubes For Mesa DC-3 Amp.......
Replies: 2
Views: 73

Re: Tubes For Mesa DC-3 Amp.......

And what in terms of your playing needs would as you say “ sound fabulous “?
by Stevem
Thu May 02, 2024 10:06 am
Forum: Technical Discussion
Topic: Can I use 6v6's in a 69 Super Reverb ?
Replies: 16
Views: 384

Re: Can I use 6v6's in a 69 Super Reverb ?

If you start reducing the power supply voltage enough then what you like about the amps preamp section will be lost and at that point your truly better off to keep the amp as it is and open up your wallet to get a attenuator box on the output of the amp.
by Stevem
Wed May 01, 2024 9:34 pm
Forum: Technical Discussion
Topic: Can I use 6v6's in a 69 Super Reverb ?
Replies: 16
Views: 384

Re: Can I use 6v6's in a 69 Super Reverb ?

The only time I used 6V6 outputs at that high a voltage was in a Highwatt 50, and they where JJ brand since they are stated to be good up to 500 volts, and after having them in the high watt I do not question that.
by Stevem
Tue Apr 30, 2024 8:58 pm
Forum: Technical Discussion
Topic: Fender question
Replies: 10
Views: 269

Re: Fender question

All that has to be done is to remove a knob from the amp in question and compare.

This is front pot board and a chassis mounted pot for comparison.
by Stevem
Tue Apr 30, 2024 10:12 am
Forum: Technical Discussion
Topic: What should I build?!?
Replies: 7
Views: 228

Re: What should I build?!?

Silvertone 1484 with KT66 outputs.
by Stevem
Fri Apr 26, 2024 9:19 pm
Forum: Technical Discussion
Topic: Add an HT Fuse?
Replies: 10
Views: 354

Re: Add an HT Fuse?

Just to be 100% clear, my reasoning for what I posted is grounded in many decades of replacing power transformers in amps that have only a mains Fuse. In terms of a vintage amp that’s seen 40 plus years of use ( effects of heat accumulation) and the situation of repetitive blowing of the mains fuse ...
by Stevem
Fri Apr 26, 2024 7:51 pm
Forum: Technical Discussion
Topic: Add an HT Fuse?
Replies: 10
Views: 354

Re: Add an HT Fuse?

A HT fuss will cover the whole DC side of the amp, but you mainly have filters that can go bad and output tubes. Filters will give you notice before they go south enough to pop the main fuse, but output tubes do not when they short . In light of this I would be more inclined to place in line with th...
by Stevem
Fri Apr 26, 2024 10:19 am
Forum: Technical Discussion
Topic: Does anyone recognize this amp design?
Replies: 10
Views: 473

Re: Does anyone recognize this amp design?

The chassis I would say is not a one of since the nuts that will tie it up into the cabinet are tack welled in, so the amp started life as something else.
by Stevem
Thu Apr 25, 2024 10:07 am
Forum: Technical Discussion
Topic: Blackvibe 6L6 Strange behavior on tone pots
Replies: 17
Views: 623

Re: Blackvibe 6L6 Strange behavior on tone pots

If your looking for any mid boost with aFender type tonestack the only way to get any of that or even get a flat response out of it is to turn the volume way up, crank full up the middle and set the bass and treble very low.
by Stevem
Tue Apr 23, 2024 10:51 pm
Forum: Technical Discussion
Topic: Does anyone recognize this amp design?
Replies: 10
Views: 473

Re: Does anyone recognize this amp design?

Well it’s got very hard to find knobs from a Heathkit from what I can tell. It’s got a T03 cased transistor mounted near the fuses so I would have to assume it’s DC powered heaters. It looks like it’s got a old paper cased filter in there and 2 other filters that could be old and out of a Highwatt o...
by Stevem
Sun Apr 21, 2024 12:07 pm
Forum: Technical Discussion
Topic: '63 Selmer Treble n bass dilemma..
Replies: 4
Views: 231

Re: '63 Selmer Treble n bass dilemma..

I have used the jtm45 PT in a 65 Fender Bassman and one would be hard pressed to hear the difference with the slightly lesser B+ voltage.

If you can surmount the mechanical difference I say go for it, and you would likely save the owner 100 bucks in the end also.