Four (4) Lonestar series Geek-out Questions

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The Mink

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Geeks only! Anybody around here know...

(1.) What exactly is happening to the circuit when you change the reverb switch between 'warm' and 'bright'? Is it filtering what goes to the reverb or the reverb itself? Etc.

(2.) What exactly is happening with the 'Thick' and 'Thicker' settings? I can tell it's pre-gain, and it sounds great for certain things, but what's it doing? Changing the frequency of Ch 2's Treble control? And if so, to what 2 frequencies?

(3.) Why does the Boost add a layer of (quite nice) upper-end grit to the sound? It makes some people leave it on all the time. Probably just more power tube breakup.

(4.) Why does the Drive section brighten up the sound as well as adding gain? Is it the different tube type? I have mixed feelings about it... leans a bit bright for single coils etc. Wonder why it isn't voiced as an extension of Ch 2's gain control.
 
1. ?
2. I think it boosts around say 1k with an extra boost on thicker.
3. ?, definitly goes through another pre-amp tube though.
4. ?
 
1) When the switch is set to 'Bright', a 250pF bypass cap is added to the front end of the reverb circuit to allow more of the highs through.

2) 'Thick' and 'Thicker' add a 250pF or 500pF bypass cap, respectively, to the CH2 tone stack. The exact frequencies which are boosted depend on the resistance of the circuit, which is variable due to the presence of variable resistors in the tone circuit (the midrange and bass controls). It's somewhere around 1K, though, as plan-x said. 'Thicker' might be around 700 or 800 Hz, I guess.

3) You're probably right, it's just the power tubes being pushed a little harder. The 'Solo' control is just a variable resistor, wired in series between the 'Output' control and ground (it increases resistance between signal and ground, causing more signal to go on to the power stage, and making the amp louder when the boost is engaged; it's a very simple circuit).

4) 12AX7 tubes (preamp tubes in general, really) are normally bright, even a little harsh, when pushed. The Drive section sits before the tone stack in the circuit, so, unlike the Gain control, it doesn't have the benefit of the tone stack to rein in the upper frequencies a bit. Rolling the Drive control back a bit and increasing the Gain will darken things up. If you're still not getting what you want, experimenting with different tubes in the V1 position might be the ticket. Electro-Harmonix preamp tubes tend to be a little on the dark side, I've noticed.
 
nemesys said:
1) When the switch is set to 'Bright', a 250pF bypass cap is added to the front end of the reverb circuit to allow more of the highs through.

2) 'Thick' and 'Thicker' add a 250pF or 500pF bypass cap, respectively, to the CH2 tone stack. The exact frequencies which are boosted depend on the resistance of the circuit, which is variable due to the presence of variable resistors in the tone circuit (the midrange and bass controls). It's somewhere around 1K, though, as plan-x said. 'Thicker' might be around 700 or 800 Hz, I guess.

3) You're probably right, it's just the power tubes being pushed a little harder. The 'Solo' control is just a variable resistor, wired in series between the 'Output' control and ground (it increases resistance between signal and ground, causing more signal to go on to the power stage, and making the amp louder when the boost is engaged; it's a very simple circuit).

4) 12AX7 tubes (preamp tubes in general, really) are normally bright, even a little harsh, when pushed. The Drive section sits before the tone stack in the circuit, so, unlike the Gain control, it doesn't have the benefit of the tone stack to rein in the upper frequencies a bit. Rolling the Drive control back a bit and increasing the Gain will darken things up. If you're still not getting what you want, experimenting with different tubes in the V1 position might be the ticket. Electro-Harmonix preamp tubes tend to be a little on the dark side, I've noticed.
Click to expand...



I wish I was as smart as you! :wink:
 
Killer responses here! I'm still thinking about changing my Drive tube to something dark if there's a chance it might work. Whenever I engage the Drive section I have to turn my guitar's tone control down to about half.
 

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