barneyg42 Posted August 2, 2010 Share Posted August 2, 2010 Took delivery of the above today, got it pretty cheap so not expecting much. So I set it up with my Acme LowB in the office at work and gave it a work out. Not as loud as my HA3500 and I was having to crank it a bit. I set the input so it was not clipping and the output was at about 1-2 o'clock, far more than the Hartke. Got some reasonable sounds, is a back up really but had to be sure it wouldn't blow the Hartke away. Anyway, I was giving it a bit of slap and tickle and when I pulled the G string hard up in the E/D area it cut out and the fan kicked in. Switched off and on and it was ok. It seemed if I boosted the mids button it was over cooking it so I switched the button out. Again it seemed ok but then again when popped on the top end it again cut out, fan on, same result. Now if I played the bottom end as is my usual style and any fingerstyle widdling up the top it was all ok. Also ok with my pedal, distortion, octave , the lot. Could it be it doesn't like my speaker? Seems ok with the Hartke so I'm not sure. The ohmage is a perfect match, 400watt into 4ohms and a 4 ohm cab. No matter how much thumping I did on the bottom end (5 string) it wouldn't cut. Quote Link to comment Share on other sites More sharing options...
simondee Posted August 3, 2010 Share Posted August 3, 2010 I've got an old Quad IV and had exactly the same problem. These heads are very sensitive to cabs, and if it doesn't like the cab it's hooked up to for whatever reason then it will start cutting out regularly. My EBS cab was on its last legs and the amp techs couldn't find a thing wrong with the head. So I'd get the cab looked at. There's something going on there that doesn't agree with the 'wick. Quote Link to comment Share on other sites More sharing options...
barneyg42 Posted August 3, 2010 Author Share Posted August 3, 2010 [quote name='simondee' post='913664' date='Aug 3 2010, 11:10 AM']I've got an old Quad IV and had exactly the same problem. These heads are very sensitive to cabs, and if it doesn't like the cab it's hooked up to for whatever reason then it will start cutting out regularly. My EBS cab was on its last legs and the amp techs couldn't find a thing wrong with the head. So I'd get the cab looked at. There's something going on there that doesn't agree with the 'wick.[/quote] Was there anything wrong with your cab in the end? Quote Link to comment Share on other sites More sharing options...
stefBclef Posted April 14, 2012 Share Posted April 14, 2012 [quote name='barneyg42' timestamp='1280769717' post='913062'] Took delivery of the above today, got it pretty cheap so not expecting much. So I set it up with my Acme LowB in the office at work and gave it a work out. Not as loud as my HA3500 and I was having to crank it a bit. I set the input so it was not clipping and the output was at about 1-2 o'clock, far more than the Hartke. Got some reasonable sounds, is a back up really but had to be sure it wouldn't blow the Hartke away. Anyway, I was giving it a bit of slap and tickle and when I pulled the G string hard up in the E/D area it cut out and the fan kicked in. Switched off and on and it was ok. It seemed if I boosted the mids button it was over cooking it so I switched the button out. Again it seemed ok but then again when popped on the top end it again cut out, fan on, same result. Now if I played the bottom end as is my usual style and any fingerstyle widdling up the top it was all ok. Also ok with my pedal, distortion, octave , the lot. Could it be it doesn't like my speaker? Seems ok with the Hartke so I'm not sure. The ohmage is a perfect match, 400watt into 4ohms and a 4 ohm cab. No matter how much thumping I did on the bottom end (5 string) it wouldn't cut. [/quote] Hey barneyg42 - did you find out what the problem was in the end? I am thinking about buying a Pro fet IV so would appreciate seeing how you have got on with it since you bought it? Ta Quote Link to comment Share on other sites More sharing options...
barneyg42 Posted April 14, 2012 Author Share Posted April 14, 2012 I took it to a tech who couldn't find what was going on, he then wired the fan to be on permanently and it was ok, needless to say it was a bit noisy and I've moved on from it now. It's just sitting in my storage as a spare. I suppose there was some sort of overheating issue although the problem started from straight after switching on so not a lot of chance to get hot. It appears the speaker wasn't the problem as the tech was running it into his diagnostic equipment. Seemed a good versatile sound when working properly, had to be cranked a bit to get the volume though! I found the Hartke 3500 a far better unit with great tone shaping and fantastic headroom. I've gone down the pre amp/power amp route now though. Quote Link to comment Share on other sites More sharing options...
stefBclef Posted April 14, 2012 Share Posted April 14, 2012 So the Hartke 3500 is your backup?! That sounds like a good situation to be in! Quote Link to comment Share on other sites More sharing options...
lobematt Posted April 19, 2012 Share Posted April 19, 2012 [quote name='stefBclef' timestamp='1334394954' post='1615518'] Hey barneyg42 - did you find out what the problem was in the end? I am thinking about buying a Pro fet IV so would appreciate seeing how you have got on with it since you bought it? Ta [/quote] I use the profet and have never had that problem but have always used it with WW cabs! Hope that helps! Quote Link to comment Share on other sites More sharing options...
MarkBassChat Posted April 20, 2012 Share Posted April 20, 2012 [quote name='barneyg42' timestamp='1334396011' post='1615545'] I took it to a tech who couldn't find what was going on, he then wired the fan to be on permanently and it was ok, needless to say it was a bit noisy and I've moved on from it now. It's just sitting in my storage as a spare. I suppose there was some sort of overheating issue although the problem started from straight after switching on so not a lot of chance to get hot. It appears the speaker wasn't the problem as the tech was running it into his diagnostic equipment. Seemed a good versatile sound when working properly, had to be cranked a bit to get the volume though! I found the Hartke 3500 a far better unit with great tone shaping and fantastic headroom. I've gone down the pre amp/power amp route now though. [/quote]I'd say that this is a very simple problem to be found and fixed. It looks like it is related to overheating. Most probably the bias is not set up correctly. There is a mini pot for this on the power amp board. But don't touch it if you don't how to use it. Take the amp to a tech that knows what means "set up a bias in an amp". It may be also a problem w thermistors (heat sensors) in the amp. In any case this is a problem that can be easily diagnosed. Of course the amp is not that strong as Hartke 3500 so you cannot expect the same power. Mark 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.