I have a single Grommes LJ-6 mono amp and since I have enough stereo gear I think I would like to use it as a guitar amp. I have found a review and schematics here http://www.grommesprecision.com/grommes/assets/pdf/littlejewelreview.PDF. I haven't worked on any electronics in a while so I could use a little walk through. Is there more to it then just changing one of the rca's to a 1/4" jack but I am not sure what.
I suggest you compare the circuit to a Fender or other amp of your liking - and change the circuit to match. The preamp is equalized for RIAA phono - you want a flat response. The tone controls will have little affect in the guitar frequency range. The large amount of negative feedback will result in an abrupt transition into nasty distortion as you overdrive it. The makers of guitar amps have learned how to make good-sounding amps - take advantage of their experience.
Looks like a solid base to build a Fender deluxe 5E3 clone...
deluxe_5e3_schem.pdf
You can even buy a loaded_fender_5e3_tweed_deluxe board and start from there.
The Grommes, the way it is, will simply sound bad for guitar...
deluxe_5e3_schem.pdf
You can even buy a loaded_fender_5e3_tweed_deluxe board and start from there.
The Grommes, the way it is, will simply sound bad for guitar...
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Looks like this has been done before.
Grommes Little Jewel conversion
Custom Designed Guitar Tube Amp
I am now debating if I should find a matching amp to make a stereo setup for some reason, sell it or make it a guitar amp.
Looking at the circuit could this design be made to sound good by today's standards without totally gutting it and redesigning it?
*edit* Can anyone confirm the pricing on this ebay post? http://cgi.ebay.com/Grommes-Precisi...emQQptZLH_DefaultDomain_0?hash=item35a3b09e58
I thought these amps sold for $20-$50 now a days.
Grommes Little Jewel conversion
Custom Designed Guitar Tube Amp
I am now debating if I should find a matching amp to make a stereo setup for some reason, sell it or make it a guitar amp.
Looking at the circuit could this design be made to sound good by today's standards without totally gutting it and redesigning it?
*edit* Can anyone confirm the pricing on this ebay post? http://cgi.ebay.com/Grommes-Precisi...emQQptZLH_DefaultDomain_0?hash=item35a3b09e58
I thought these amps sold for $20-$50 now a days.
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Someone is asking a bit much...
I agree, amps age like milk, not like wine...
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