Oh The Tone

I'm working at home today. Always tempting to pick up a guitar.

So this afternoon I plugged the Nightbird into Channel 1 on the Thunderbird amp, then jumpered the Thunderbird over to the bass channel on the Thunderbass with the 2X10 cab. Bass way up, treble almost off on the Thunderbass, the notch filter in the low position. Treble up, bass nearly off on the Thunderbird, a bit of tremolo and about 1/2 on the reverb.

Oh my. I'm a convert. Opening up the guitar tone pot brings up the TBird and yields an great dynamic range in tone and volume. Flipping the pickups out of phase adds some sort of "spaciousness" to the sound - hard to explain, sort of a very subtle and cool chorus effect.

This could be much fun, although it's not exactly the rig you want to carry over to a friend's or load in at the next open stage. Cost me at least an hour's work. So far.

Work is overrated!

The tbird Has a pre-amp out John?

Ditto the part about work. I'm taking a mini-vacation for the next couple of days. Nobody home but me and the Guilds. :wink:

Default said:

The tbird Has a pre-amp out John?

Click to expand...

No pre-amp out. The guitar is plugged into Tbird Input 1 on Channel 1, with a guitar cable from Input 2 (same channel) to Input 1 on the Bass preamp side of the Tbass.

Just runs a duplicate original input signal to the second amp (I believe).

john_kidder said:

... Cost me at least an hour's work. So far.

Click to expand...

Cheap at twice the price ... have to turn it up whenever the opportunity comes along! CJ

Ok, blame it on too little sleep and too much cold medicine.

No blame - but watch that Nyquil.

Just played the X400 for a few minutes with its big fat smooth strings and its big fat (non-original) humbuckers. Now I know why bass players look that way.

john_kidder said:

The guitar is plugged into Tbird Input 1 on Channel 1, with a guitar cable from Input 2 (same channel) to Input 1 on the Bass preamp side of the Tbass. Just runs a duplicate original input signal to the second amp (I believe).

Click to expand...

Yes; dual-mono but not completely benefitting from the usual 'daisy-chaining' trick which takes the output of one channel and uses it for the input of the other channel...gain city as it were ... Not for everyone and if the faceplate isn't drilled for out/in jacks, it can still be done by re-routing the channel 1 signal to a switch installed in place of the other channel 1 jack and routing the switch output to channel 2. For considerably more than it's worth, I'd be happy to fly up there and ...

capnjuan said:

Yes; dual-mono but not completely benefitting from the usual 'daisy-chaining' trick which takes the output of one channel and uses it for the input of the other channel...gain city as it were...

Click to expand...

Edited the original post back to "jumpered" instead of "daisy-chained". I can see how I misled Default that way - sorry.

What do amps do with an input signal that hot? Wouldn't they overdrive at far lower gain or just clip the final output?

capnjuan said:

For considerably more than it's worth, I'd be happy to fly up there and ...

Click to expand...

For considerably less than it would cost, I'd be happy to pay to get you up. Bring a soldering iron and a few caps and tubes, I'll meet you at the airport.

john_kidder said:

What do amps do with an input signal that hot? Wouldn't they overdrive at far lower gain or just clip the final output?

Click to expand...

Both; the channel 2 preamp tube and driver/phase inverter are overdriven to distortion / clipping which produces the desirable even-order harmonics. What's lost is the range of usable additional volume before it's just sonic mud coming out of the speaker.

If you've had a little too much Canadian Club and find someone else's Thunderbird (V2 shown below), this is the idea; pick up the signal downstream from the Channel 1 preamp and jumper it to the hot side of the Channel 1 second input jack. Remove the 82K input resistor. Then jumper the the Channel 1 secondary jack to either of the Channel 2 input jacks with one of those shortie 1/4" jumper cables for tying pedals together - instant Slash!



I don't know the V2 Thunderbird layout but if the signal climbs off the pc board to that slide switch, I'd pick the signal up there. At that point, the signal would be divided between Channel 1 and 2. To get all the Channel 1 preamp output would require either a switch to open the circuit or permanently disconnecting it. Otherwise, it would be half-slasshed.

About the trip ... Ok ... I'll just email you the tubes :wink: CJ