Bobo_Grimmer Posted May 22, 2010 Share Posted May 22, 2010 (edited) Let me start by saying sorry if there already is a random small questions thread but i couldn't see one. I thought this might be handy for little questions that don't ready need their own thread for. Good idea? Anyhoo my wee question is : Im having a strange, pos grounding problem, with my ampeg B2RE. Is there a ground lift option on it? Inside maybe? Or dose its design not need one? I can go into more detail of why I'm asking this but I'm in a coffiee shop descussing amps with a young chap at the moment and typing on a phone is tedious. Edited May 22, 2010 by Bobo_Grimmer Quote Link to comment Share on other sites More sharing options...
Prime_BASS Posted May 22, 2010 Share Posted May 22, 2010 What do you mean? Does it buzz when you guitar is plugged n and it's just on? Or does the DI output buzz and generate noise. I think you mean, the second one. In that case there is usually a ground lift button on the back close to DI Section. Otherwise it could be a lot of reasons. Like guitar sheilding, poor cables even electric outlets. Did you try google? Quote Link to comment Share on other sites More sharing options...
Bobo_Grimmer Posted May 22, 2010 Author Share Posted May 22, 2010 [quote name='Prime_BASS' post='845020' date='May 22 2010, 12:30 PM']What do you mean? Does it buzz when you guitar is plugged n and it's just on? Or does the DI output buzz and generate noise. I think you mean, the second one. In that case there is usually a ground lift button on the back close to DI Section. Otherwise it could be a lot of reasons. Like guitar sheilding, poor cables even electric outlets. Did you try google?[/quote] hum... it is a weird one. Right i'll try and type out a bit more info now i'm home. (wish me luck! not to good at explaining my self) the D.I. has no ground lift function. my bass into my floor deck into the front of the amp. that's as it should be. then i have the output from my effects loop on the back of the amp going to my rack tuner, out from there to a compressor, out from there back into the input of the effects loop. i have the D.I. (XLR) going to my desk and thats where i have my headphones plugged in. When i have everything switched on, when i first sit down to play, the bass signal is very week. It sounds all toppy with no definition. If you turn the input to the preamp up more than an 8th it distorts but not a normal preamp overdriven type distortion but more a crackly not good sounding distortion. Now if i disconnect the effects loop stuff and the D.I then plug the D.I. back in seems to fix it. as in the signal goes back to normal. Sounding all ampeg like and well just lovely. So i plug the effects loop stuff back in and everything works as normal. odd huh! Now i say about the ground lift, Maybe a mod i can do if necessary, because it kinda sounds like the signal is being pulled down by something. The floor deck has a 'wall wort' 9V adaptor, the compressor has a kettle lead, the rack tuner and the amp also have kettle leads. they are all on the same power strip and the desk is on a different one. Is that amy help? Quote Link to comment Share on other sites More sharing options...
escholl Posted May 22, 2010 Share Posted May 22, 2010 [quote name='Bobo_Grimmer' post='845249' date='May 22 2010, 06:09 PM'] hum... it is a weird one. Right i'll try and type out a bit more info now i'm home. (wish me luck! not to good at explaining my self) the D.I. has no ground lift function. my bass into my floor deck into the front of the amp. that's as it should be. then i have the output from my effects loop on the back of the amp going to my rack tuner, out from there to a compressor, out from there back into the input of the effects loop. i have the D.I. (XLR) going to my desk and thats where i have my headphones plugged in. When i have everything switched on, when i first sit down to play, the bass signal is very week. It sounds all toppy with no definition. If you turn the input to the preamp up more than an 8th it distorts but not a normal preamp overdriven type distortion but more a crackly not good sounding distortion. Now if i disconnect the effects loop stuff and the D.I then plug the D.I. back in seems to fix it. as in the signal goes back to normal. Sounding all ampeg like and well just lovely. So i plug the effects loop stuff back in and everything works as normal. odd huh! Now i say about the ground lift, Maybe a mod i can do if necessary, because it kinda sounds like the signal is being pulled down by something. The floor deck has a 'wall wort' 9V adaptor, the compressor has a kettle lead, the rack tuner and the amp also have kettle leads. they are all on the same power strip and the desk is on a different one. Is that amy help? [/quote] actually it sounds like it could be a bad connection -- does this procedure for removing the problem work every time? i mean, if you were to do it 5 times in a row, would the results be the same everytime? Or did unplugging the re-plugging the cables just fix it that one time? Quote Link to comment Share on other sites More sharing options...
Bobo_Grimmer Posted May 22, 2010 Author Share Posted May 22, 2010 [quote name='escholl' post='845272' date='May 22 2010, 06:47 PM']actually it sounds like it could be a bad connection -- does this procedure for removing the problem work every time? i mean, if you were to do it 5 times in a row, would the results be the same everytime? Or did unplugging the re-plugging the cables just fix it that one time?[/quote] Yeah this seems to fix it every time it's happened so far. i've only sat down and played with this set up about 4 times in the last week or so, the amp i have only just got. I might try a little bit more of an investigation into the bad connection idea. try swapping out some of the patch leads i have going between all the rack gear. maybe one of those is causing a problem. My compressor works fine as it's the same one i use for other stuff. I have already tried a few XLR leads to the desk and tried different channels on the desk. thought it could have been a problem with a pre on the desk . What worried me was the way it crackles/ distorts...... hum thinking about it it does sound like a 'connection' kind of crackle/distortion.... *scratches chin* After tea i'll try turning everything on and see if it starts up with this problem again and then experiment a bit and get back to you. thank you for the response (Y) Quote Link to comment Share on other sites More sharing options...
Merton Posted May 24, 2010 Share Posted May 24, 2010 [quote name='Bobo_Grimmer' post='844906' date='May 22 2010, 10:10 AM']Anyhoo my wee question is : Im having a strange, pos grounding problem, with my ampeg B2RE. Is there a ground lift option on it? Inside maybe? Or dose its design not need one?[/quote] [url="http://basschat.co.uk/index.php?showtopic=194"]Have a lookie here![/url] Quote Link to comment Share on other sites More sharing options...
Stylon Pilson Posted May 24, 2010 Share Posted May 24, 2010 [quote name='Bobo_Grimmer' post='844906' date='May 22 2010, 10:10 AM']Let me start by saying sorry if there already is a random small questions thread but i couldn't see one. I thought this might be handy for little questions that don't ready need their own thread for.[/quote] Seems like a bad idea - if you create a new topic, with a suitable subject line, then knowledgeable people will see it and respond to it. But if you bury a question amongst a thread like this, which is full of responses and discussion, then you're really ruining your chances of it being seen. S.P. Quote Link to comment Share on other sites More sharing options...
Commando Jack Posted May 28, 2010 Share Posted May 28, 2010 [quote name='Stylon Pilson' post='846470' date='May 24 2010, 01:25 PM']Seems like a bad idea - if you create a new topic, with a suitable subject line, then knowledgeable people will see it and respond to it. But if you bury a question amongst a thread like this, which is full of responses and discussion, then you're really ruining your chances of it being seen. S.P.[/quote] Case in point: no other questions have been added to this thread as far as I can see! Quote Link to comment Share on other sites More sharing options...
Ghost_Bass Posted May 28, 2010 Share Posted May 28, 2010 (edited) Ok, i'll add another question... Is it possible to know (or at least predict) the power handling (in W) of a driver without having especific machines to measure that? I have two 6" drivers at home that came with a old and brandless speaker (wich is long departed) and all i can know about they is their impedance and measurements. No serial or brand on them whatsoever... Is there any kind of equation to predict it's power handling or is just putting a specific frequency through it and measuring it? Edited May 28, 2010 by Ghost_Bass Quote Link to comment Share on other sites More sharing options...
Stylon Pilson Posted May 28, 2010 Share Posted May 28, 2010 [quote name='Ghost_Bass' post='850247' date='May 28 2010, 12:21 PM']Is it possible to know (or at least predict) the power handling (in W) of a driver without having especific machines to measure that? I have two 6" drivers at home that came with a old and brandless speaker (wich is long departed) and all i can know about they is their impedance and measurements. No serial or brand on them whatsoever... Is there any kind of equation to predict it's power handling or is just putting a specific frequency through it and measuring it?[/quote] It's calculated by taking one speaker from a batch, putting power through it until the voice coil melts, and then labelling the remaining speakers with that power rating. So if you're willing to sacrifice one of your 6" speakers, you could discover the power handling of the other one. S.P. Quote Link to comment Share on other sites More sharing options...
LawrenceH Posted May 28, 2010 Share Posted May 28, 2010 [quote name='Stylon Pilson' post='850287' date='May 28 2010, 01:18 PM']It's calculated by taking one speaker from a batch, putting power through it until the voice coil melts, and then labelling the remaining speakers with that power rating. So if you're willing to sacrifice one of your 6" speakers, you could discover the power handling of the other one. S.P.[/quote] You could maybe fire it up in an arbitrary box with a measurement system, successively doubling the power and letting it equilibrate for a few mins, and look for when thermal compression starts to kick in noticeably - this'd give you a rough and ready idea? Quote Link to comment Share on other sites More sharing options...
Ghost_Bass Posted May 28, 2010 Share Posted May 28, 2010 [quote name='LawrenceH' post='850351' date='May 28 2010, 02:34 PM']You could maybe fire it up in an arbitrary box with a measurement system, successively doubling the power and letting it equilibrate for a few mins, and look for when thermal compression starts to kick in noticeably - this'd give you a rough and ready idea?[/quote] I like your idea better than Stylon's . i'm not DIY'ing anything with them for now but i took the opportunity of this thread to take this question of my head. thanks to all Quote Link to comment Share on other sites More sharing options...
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