TS7 hot mode reducing gain?

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crispycircuit
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Post by crispycircuit »

I really enjoy the sound of the hot mode, however I would like to reduce the gain. The volume control is turned down a lot and it's too sensitive /hard to control.... Is it possible to keep the hot mode sound and lower the gain, so the volume control has a less touchy action?

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alexradium
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Post by alexradium »

crispycircuit wrote:I really enjoy the sound of the hot mode, however I would like to reduce the gain. The volume control is turned down a lot and it's too sensitive /hard to control.... Is it possible to keep the hot mode sound and lower the gain, so the volume control has a less touchy action?
post schematic

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FiveseveN
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Post by FiveseveN »

When people say "gain" they usually mean saturation / distortion, especially when talking about a dirt box.
But as I understand you need less output volume, right? Easily done by using a larger value resistor before the volume pot. That would be R49 in this schematic: http://www.matsumin.net/diy/bunkai/Iban ... S7_sch.BMP
100K would give you half the max volume of the stock unit. See how much you need and use the resistive divider formula to pick your value.
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Post by crispycircuit »

I was hoping to reduce the gain factor in the second stage, which looks to be the tone stage. Is the transistor in the last stage for buffering? Thx for the reply....

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Post by FiveseveN »

The second op amp stage doesn't provide make-up gain, just some treble boost at the higher tone pot settings. And yes, both transistors are discrete buffers.
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crispycircuit
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Post by crispycircuit »

Well then how do I knock down the volume and keep the hot mode.....Would installing a 100k resistor in front of the volume pot work? And would the sound be the same? Or could a 25K pot drain some signal to ground and sound the same. Where do you buy pots to fit the circuit board.??? :?:

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Post by FiveseveN »

I don't know what the "hot mode" is and you shouldn't assume other forum members do either.
A smaller value pot would not help since it is driven by a (fairly) low output impedance buffer. You don't need to "install a 100k resistor in front of the volume pot", that's what R49 is. Just swap it for a 100K or whatever you find suitable.
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Post by crispycircuit »

SUCESS !! Replace R49 1k with 100k 1/4 watt. Now the range is controllable with the Level knob.....It sounds the same and the regular TS7 sertting is also very useable. Very happy with my pedal. Thx for the expert help. 1 resistor couldn't be more simple. I recommend an electric Vaccum solder sucker (like the Hako 808) to keep from messin the board up. Tight area as they use 1/8 watt resistors and the traces are close together. A very nicepedal as is, however with this simply change both modes are excellent. OK mission accomplished.....You guys rock!!

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