Jet City JCA20H

[BSS]

Hey guys, I just got my JCA20H, and so far it's sounding pretty good. I got it used from MF, so I'm trying to figure out if there is anything electrically wrong with it. The only two things I notice are:

1) with the gain up above 6 or 7 and the volume down around 1, it seems pretty fizzy in the treble. Now, with some volume it goes away, so I'm guessing it's normal

2) the LED randomly dims and brightens. I'm guessing this is a problem with the LED and not the amp circuit.

Other than that, it sounds pretty darn good, gets plenty loud, no other noticable problems, so I'm hoping the fizz is normal and a re-tube will at least help it.

 

[stephen sawall]

I only played one for a few minutes and liked it.

 

[JerryP]

The brightness at low volumes is normal. The power indicator light is a light bulb which works off the amps heater circuit. It could be a poor connection in the light bulb socket or a bulb issue.
Jerry

 

[BSS]

The brightness at low volumes is normal. The power indicator light is a light bulb which works off the amps heater circuit. It could be a poor connection in the light bulb socket or a bulb issue.
Jerry

Thanks Jerry, kinda what I guessed. I can kind of dial it out, but with the gain up high, it gets pretty hairy. It is a VERY bright amp.

Any plans to do any mods on these?

 

[JerryP]

I've already modded one. I have info and video on my site.
Jerry

 

[BSS]

I've already modded one. I have info and video on my site.
Jerry

Awesome, didn't realize that. I'll check it out!

 

[bmf5150]

Jerry your mods sound great......

 

[CaseyCor]

The brightness at low volumes is normal. The power indicator light is a light bulb which works off the amps heater circuit. It could be a poor connection in the light bulb socket or a bulb issue.
Jerry

Thanks Jerry, kinda what I guessed. I can kind of dial it out, but with the gain up high, it gets pretty hairy. It is a VERY bright amp.

Any plans to do any mods on these?

I agree with this, for sure. When I played the JAC20H, it was super bright, especially at low volumes. No matter what I did, I couldn't get rid of it.

It is a cool amp though. Perhaps running a GEQ in the loop might tame the highs a bit. I'm sure it would open the amp up, but I guess I say that about every amp I love a graphic EQ in the loop of an amp. It's my form of boost I guess.

 

[BSS]

The brightness at low volumes is normal. The power indicator light is a light bulb which works off the amps heater circuit. It could be a poor connection in the light bulb socket or a bulb issue.
Jerry

Thanks Jerry, kinda what I guessed. I can kind of dial it out, but with the gain up high, it gets pretty hairy. It is a VERY bright amp.

Any plans to do any mods on these?

I agree with this, for sure. When I played the JAC20H, it was super bright, especially at low volumes. No matter what I did, I couldn't get rid of it.

It is a cool amp though. Perhaps running a GEQ in the loop might tame the highs a bit. I'm sure it would open the amp up, but I guess I say that about every amp I love a graphic EQ in the loop of an amp. It's my form of boost I guess.

No loop on the 20 watter though. I agree with you about an EQ in the loop, I run one in the loop of my blackstar sometimes, and it works wonders for really tweaking in your tone.

 

[JerryP]

Jerry your mods sound great......

Thank you!
Jerry