Hi all,
I just had a question about the effects loop on a roland JC40. Could any damage be caused by using this as an auxillary input (with my phone)? I've use my phone for a metronome app when I practice through headphones but am afraid to continue doing this out of fear of damaging components of the amp. For clarity, my instrument is plugged into the front input channel, headphones through the headphone jack in the back, and phone plugged into the effects input loop on the back side. Thanks for any input.
C
I just had a question about the effects loop on a roland JC40. Could any damage be caused by using this as an auxillary input (with my phone)? I've use my phone for a metronome app when I practice through headphones but am afraid to continue doing this out of fear of damaging components of the amp. For clarity, my instrument is plugged into the front input channel, headphones through the headphone jack in the back, and phone plugged into the effects input loop on the back side. Thanks for any input.
C
It should be safe, typical headphone out level is between 100 and 200 mV RMS, well within capabilities.
Doesn´t your amp have a dedicated "CD IN" or similar?
Doesn´t your amp have a dedicated "CD IN" or similar?
No unfortunately it doesn't. Do you think it would be safer to plug it into the main R stereo input and just split the sound? Thanks for your response.
Owner manual, block diagram.
Roland JC-40 Jazz Chorus Guitar Amplifier吉他擴大音箱 Owner's Manual | manualzz.com
Schematic:
https://music-electronics-forum.com/filedata/fetch?id=922362
This is a DSP amp. Input is minimally boosted than fed to an ADC for tone, gain, and effects. Final is an analog TDA2050 power chip.
In true digital tradition, the schematic is a cut-up puzzle of AD0 and MCK go-to links. I can't figure it all. But it looks like all in/out is thoroughly protected with large resistors or diodes.
And how loud does this metronome have to be? Start silent, sneak up slowly.
Roland JC-40 Jazz Chorus Guitar Amplifier吉他擴大音箱 Owner's Manual | manualzz.com
Schematic:
https://music-electronics-forum.com/filedata/fetch?id=922362
This is a DSP amp. Input is minimally boosted than fed to an ADC for tone, gain, and effects. Final is an analog TDA2050 power chip.
In true digital tradition, the schematic is a cut-up puzzle of AD0 and MCK go-to links. I can't figure it all. But it looks like all in/out is thoroughly protected with large resistors or diodes.
And how loud does this metronome have to be? Start silent, sneak up slowly.
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Jc40
Thanks for the post of the schematic. If it helps at all, the phone is a hauwei P30 lite. I haven't been able to find the line output of this device online.
The metronome does not need to be loud at all so I can start at low volume and see how it goes. What would I expect if I were causing damage? I suppose it would be obvious? I just bought a stereo 1/8" TRS jack to two 1/4" TS to try it out.
My apologies for my ignorance, but you say the in/outs are protected? Does that mean if too large voltages are reached, the diodes will prevent the circuit from getting fried? Thanks for all of your input!
Thanks for the post of the schematic. If it helps at all, the phone is a hauwei P30 lite. I haven't been able to find the line output of this device online.
The metronome does not need to be loud at all so I can start at low volume and see how it goes. What would I expect if I were causing damage? I suppose it would be obvious? I just bought a stereo 1/8" TRS jack to two 1/4" TS to try it out.
My apologies for my ignorance, but you say the in/outs are protected? Does that mean if too large voltages are reached, the diodes will prevent the circuit from getting fried? Thanks for all of your input!
It is a guitar amp. It is meant to be used by (among others) drunk/stoned teenagers while their parents are away. Roland has 50+ years of experience with such customers. It should be VERY hard to hurt it.