TomCat Riaan wrote If you can get string feedback from the volume, you're probably playing too loud. Whoops.... ? Remember that uncontrolled acoustic feedback is a loudspeaker killer......causes the voice coils of the loudspeaker to dramatically head up and burns the loudspeaker out.
stu So I plugged the pre-amp into the hi-fi I got a crap tone ? I used the headphones out fro the pre-amp and when I have headphones plugged into it it sounds fine. So my logic tells me that this is wierd.
Tamago Impedance mismatch is present. Headphone outputs are notoriously bad, trust me I used to do that in my mis-spent youth until an engineer taught me better and showed me to rather open up the thing and get a line level from the signal source just before the volume control. All I can suggest is if you have to use the headphone output, we need to terminate it in its characteristic impedance (usually 32-300 ohms) and then build a pad, to get to line level. That could improve things. I could draw you a circuit if you feel up to soldering.
chris77 Potential thread hijack, sorry, but I have to ask ? Relating to the headphone jack comment - I own a vox vt 30. Brilliant little amp. Easy to use and sounds great.... If you dont use headphones. I almost always play through phones, so its a bit of a bugger. Is there any way to mod it so the headphone sound is closer to the speaker sound?
Tamago chris77 wrote Potential thread hijack, sorry, but I have to ask ? Relating to the headphone jack comment - I own a vox vt 30. Brilliant little amp. Easy to use and sounds great.... If you dont use headphones. I almost always play through phones, so its a bit of a bugger. Is there any way to mod it so the headphone sound is closer to the speaker sound? I am having the same problem with my guitar amp at home. Rest assured I am working on solving the problem. I might have a solution by next week. I also have to play through 'phones because that's the only time I have during the week, which is late at night.
Tamago There are many reasons for that. Some amps have dedicated headphone amp stages. Mine does, which is so far removed from reality it is a joke. I am going to get the schematic for you amp and have a look see this afternoon.
Tamago @ stu Try this with your setup and let me know please This is all I can do until my hosting comes through today, for my personal website, then I will link to pics stored there. @chris77, I am now working on your problem....
TomCat Also remember that on some amps the headphone output also includes a loudspeaker simulator (A tone circuit) that emulates the loudspeaker tone to the headphones. It gives a relatively close representation (similar to amp sims in effects units), but is not exactly the same as the actual loudspeaker tone. This will explain why some amps headphone O/P sound is OK while others do not.
Tamago You are quite correct. My amp doesn't have one, and I am willing to bet that VOX doesn't either. chris77- I can't get a schematic for your amp as I wanted to check where it is tapping off, but, give me a few days I am going to try and build a tone circuit for mine and see how close, or not I can get to the speaker.
Gearhead Tamago wrote Try this with your setup and let me know please Might want to list if the pot is linear/audio/logarithmic....
Tamago Logarithmic or audio pot of course. To test using a normal linear pot should be okay, and then replaced with the proper type.
