bigjohn Posted June 9, 2009 Share Posted June 9, 2009 [url="http://www.ampeg.com/pdf/SVTIIP.pdf"]Ampeg SVT iip Manual[/url] The pre is excellent condition and has just been serviced and revalved. The valves were checked by Watford Valves when I bought them, and again by the tech who serviced the amp. [url="http://www.bkelec.com/Pro/Amplifiers/MXF1200D.htm"]BK MXF 1200d[/url] 2 x 4Ohm [url="http://www.acmebass.com"]Acme Low b2s[/url] Should be a monster. So far, unfortunately not. It's [i]far[/i] too easy to get the power amp to clip. Not only does it clip. The power amp also has a protection circuit which cuts out any output if you drive it too hard. Which is annoying, especially at a gig when your new 600W per channel amp can't even keep up with a drummer without continuously cutting out. Considering it's 600W per channel, this rig is currently no louder than my 100W Marshall JCM800 (now sold) was with these speakers. And I never had any trouble with that cutting out. Dood has been very helpful when I've asked him about this. He was my first port of call as he's owned an MXF1200d and an ampeg pre-amp before. Thanks to his direction I've got the amp to work without clipping by using the EQ and dropping out all the "low" and 100Hz band. And removing most of the Bass through the parametric EQ. He's suggested getting a high pass filter as a possible solution. Anybody else got any thoughts? Confused. John Quote Link to comment Share on other sites More sharing options...
deksawyer Posted June 9, 2009 Share Posted June 9, 2009 I can't pinpoint the problem for you, but there's something wrong somewhere, that's for sure. Would there be much of a difference in output level between the main out jacks and the XLR out on the Ampeg? D. Quote Link to comment Share on other sites More sharing options...
bigjohn Posted June 9, 2009 Author Share Posted June 9, 2009 (edited) [quote name='deksawyer' post='509091' date='Jun 9 2009, 02:56 PM']I can't pinpoint the problem for you, but there's something wrong somewhere, that's for sure. Would there be much of a difference in output level between the main out jacks and the XLR out on the Ampeg? D.[/quote] The ampeg is rated as having a 1.0v output before EQ and upto 3.5v with. I'm not sure what the balanced out is... The manual says microphone level (-20db) or line (-0db)... The BK has an input sensitivity of 775mV. It used to run fine with a Pod, which has an input max of 5.5v Edited June 9, 2009 by bigjohn Quote Link to comment Share on other sites More sharing options...
BOD2 Posted June 9, 2009 Share Posted June 9, 2009 I'd be inclined to try connecting from the balanced out on the Ampeg and not the main outs. The level switch sets the signal level at this connector to be microphone level (low) or line level (higher). I would expect it to work at the line level setting but you could experiment with both settings of the switch. Quote Link to comment Share on other sites More sharing options...
bigjohn Posted June 10, 2009 Author Share Posted June 10, 2009 (edited) [quote name='BOD2' post='509684' date='Jun 9 2009, 10:43 PM']I'd be inclined to try connecting from the balanced out on the Ampeg and not the main outs. The level switch sets the signal level at this connector to be microphone level (low) or line level (higher). I would expect it to work at the line level setting but you could experiment with both settings of the switch.[/quote] I'll have a go at that. I haven't got any XLR cables, but I'm going to a rehearsal tonight where there will be some. The two problems I can see do this though are... 1) I'd need an XLR > 2 XLRs for both channels. 2) It leaves no balanced out for the desk. Edited June 10, 2009 by bigjohn Quote Link to comment Share on other sites More sharing options...
BOD2 Posted June 10, 2009 Share Posted June 10, 2009 [quote name='bigjohn' post='509989' date='Jun 10 2009, 10:51 AM']I'll have a go at that. I haven't got any XLR cables, but I'm going to a rehearsal tonight where there will be some. The two problems I can see do this though are... 1) I'd need an XLR > 2 XLRs for both channels. 2) It leaves no balanced out for the desk.[/quote] I realised that as well ! But this is initially just a test to see how it works on one channel using that method of input. If it works well then there are ways you can resolve the other issues. Quote Link to comment Share on other sites More sharing options...
steve-soar Posted June 10, 2009 Share Posted June 10, 2009 (edited) Have you got a lead from each main out of the SVT IIP going to each channel input of the power amp, or have you bridged the power amp? Can it work in bridge mode? How have you got the speakers wired up? I run my SVT IIP like this, one main out to channel one of my power amp in bridge mode then into a single speaker. Edited June 10, 2009 by steve-soar Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.