Proco Rat build

syscokid said:
I'm back to add about my latest BYOC Mouse adventures. I'm presenting a semi-short video clip of the Mouse with the modern LM308 transistor versus a vintage LM308 transistor that was gifted to me by @ivan H. Do any y'all hear a difference?

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Good video, well done Sysco.

The first had quite a tail off the end of the notes which gave a harsh effect. The second seemed much tighter, not so much note residue. Both had a bit more treble than I'd ideally like, but they held it in different ways; the first seemed quite glassy whereas the second had a sharper and more immediate attack.

BTW, loved that 6w 6l6 amp; I'd love one of those!
 
Ok, listening to the clip both through decent headphones & then the stereo the upper mid/high end of the TO-99 Motorola chip is noticeable, & Mr Grumpy has good ears, I also noticed the sharper more immediate attack (especially through the headphones). Both chips are producing good useable tones though, I'd be happy with a modern one.
Mr Grumpy, the Proco Rat do have a filter (tone) control so the treble can be dialed down.
How do you find the added presence control Mr Sysco?? Cheers
 
I was gonna plug in my Shure 535s to listen, but everything was so noticeable through the Yamaha THR10 that I use as my Mac mini sound that I didn't need to. I agree with Ivan and others that both sounded good, just different.

I don't have a rat, but I have a Katzenkonig - I'll be damned if I can tame it without reducing my guitar volume a fair bit...
 
Mr Grumpy said:
BTW, loved that 6w 6l6 amp; I'd love one of those!
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My Allen Amps Chihuahua (Built from a kit) is set up with a 6V6, for 6 watts of power. But the amp does have an oversized output tranny, and a 6L6 can be used for 10 watts of power if desired. A couple power resistors also need to be swapped out for switching between the two different power tubes.

Most of the amps from Allen Amps, are loosely based on Fender Blackfaced era amps. The Chihuahua takes its cue from the blackface Champ. David Allen's more modern approach to the Champ adds:
More robustly designed trannies with heavier filtering and beefed up power supply.
Adds a footswitchable mid/RAW control that also adds the capability to gradually bypass the tonestack for a more Tweedy sound.
Adds a reverb circuit!
Adds a master volume.
And the option to get this amp in a head format, or 1x8, 1x10, & 1x12 cab. I went with the 1x10.

Bunch of answers for a question that never was asked, huh? Oh well... I love giving a shout-out for Allen Amps. Top quality stuff with top quality support from Mr David Allen!

Gratuitous linky:
 
^ very nice amp indeed although unlike you not to unleash the fully power of the tranny... :D

Looked at the website, not cheap.

Is it just me or is a 6L6 a bit tighter than a 6V6 when pushed hard into distortion? 6V6s always sound nice to me when clean and a tad crunchy, but on a heavy distortion the 6L6 rules.
 
ivan H said:
Mr Grumpy, the Proco Rat do have a filter (tone) control so the treble can be dialed down.
How do you find the added presence control Mr Sysco?? Cheers
Click to expand...
As you already know, the Rat's filter control is sort of a backwards tone control. Maybe you could explain the difference more accurately?
I can easily see and hear why the added presence control is such a popular mod for the Rat pedal. Very very useful for fine tuning the highs and corresponding drive of the circuit.

Looks like it would be an easy mod for you. Probably you can just clip on the added circuit mod just to try it.

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Mr Grumpy said:
very nice amp indeed although unlike you not to unleash the fully power of the tranny... :D
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But it's there if desired. In fact, I just checked on Allen's website, and he's now offering a panel mounted switch to simplify switching between power tubes. I'm going to hit him up for more info on this... :fingersx:


Mr Grumpy said:
Looked at the website, not cheap.
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Quality... Quality... Quality!
Plus, David Allen doesn't do exports. You, your sweet wifey, and Chokdee are going to have to move to Groovy Beach!


Mr Grumpy said:
Is it just me or is a 6L6 a bit tighter than a 6V6 when pushed hard into distortion?
Click to expand...
Yup, it's just you! Just kidding... :p


Mr Grumpy said:
6V6s always sound nice to me when clean and a tad crunchy, but on a heavy distortion the 6L6 rules.
Click to expand...
Saturated 6V6's have their place too when it comes to sweet musical mayhem...

and-thats-all-ive-got-to-say-about-that.jpg
 
syscokid said:
As you already know, the Rat's filter control is sort of a backwards tone control. Maybe you could explain the difference more accurately?
I can easily see and hear why the added presence control is such a popular mod for the Rat pedal. Very very useful for fine tuning the highs and corresponding drive of the circuit.

Looks like it would be an easy mod for you. Probably you can just clip on the added circuit mod just to try it.

View attachment 41549
Click to expand...
The filter control operates like a "cut" control in that turning it up reduces or cuts highs.
When I built my Rat I used this layout
15861577574523759750408041542251.png
which has the filter operating as a normal tone control, though uses the same 100k audio taper pot as the original. Of course, this makes it very bassy for most of the pots rotation, with the high end all crammed in the last bit of the "dimed" part of the pots rotation. I quickly changed it back to how it should be.
I had wanted to build the BYOC mouse, but the Aussie distributor was out of stock. I waited over 6 months to hear from them that they were back in stock before building. They "still" haven't got them back in stock (& it's been yrs).
The "presence" control mod swaps out a 47 ohm resistor for a 1k pot. I will be adding one to mine in the near future.
Cheers
Edit:
It's a pity David Allen doesn't do exports, I have looked at his site before & would likely have one of his designs if he did. As it stands, if I enlisted someone's aid in purchasing & shipping a kit I would need to use an external 240VAC to 120VAC transformer to power it. Cheers
 
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ivan H said:
The "presence" control mod swaps out a 47 ohm resistor for a 1k pot. I will be adding one to mine in the near future.
Click to expand...
It's amazing what a 1K can do, ha ha! You'll definitely like it... :cheers:

ivan H said:
It's a pity David Allen doesn't do exports, I have looked at his site before & would likely have one of his designs if he did. As it stands, if I enlisted someone's aid in purchasing & shipping a kit I would need to use an external 240VAC to 120VAC transformer to power it...
Click to expand...
And I bet you already have one of them transformers! The rest should be easy... ;););););)
 
syscokid said:
The BYOC Mouse is Out Of Stock again.
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General Guitar Gadgets "Rodent" Rat clone kit is available. It doesn't have the clipping diode options or presence mod that the BYOC Mouse kit offers, thought both these features could be easily added to the Rodent while building.
I've thought about adding the LED & germanium diode clipping options to mine, but decided I'm happy with how it is now, stock Rat with a toggle switch selecting either "assymetrical clipping," where another 1N914 diode is added in series with the positive clipper (a bit more aggressive sounding with a small volume increase), or "very assymetrical clipping," where the positive clipper(s) are removed from the circuit by lifting their ground (very aggressive sounding & quite a bigger volume increase). To be able to footswitch in the latter feature would be great for a lead/solo boost. Cheers
 
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