Will Synth + Bass Guitar + Pedals etc. mixed blow amp?

[David Smyth]

I play in a band which requires quick transitions between my moog synthesizer (little phatty) and my 6-string bass guitar.

My last amp was a 300watt GK Backline 600 through 2 8-ohm warwick cabs.

I used my moog synth through a korg kp3 kaoss pad for effects. (line 1)

Also I used an active 6-string bass with maybe 5 boss pedals. (line 2)

These two 'lines' were mixed together with a Behringer MX400 mixer ( http://www.behringer.com/EN/Products/MX400.aspx ).

While all this was running and we jammed, the head suddenly blew the fuse and stopped working. I replaced the fuse correctly and it blew again and again. Apparently a 'tovoidal transformer' had gone in it and I have since passed the amp onto someone who is keen on fixing it for themselves.

Anyways, I thought i'd upgrade amp so I'm aquiring a GK 1001RB MARK II (750watt) head this weekend to hopefully run the same set up..

Is there any obvious or known problem with the amount of electronic gear being put into the amp? or possibly this mixer is not a good idea? was it a random happening and should I be endangering my new head?

Thanks,
David Smyth

[JimmyM]

random happening. people put synths through amps all the time.

[T-Bird]

Hi David.

I'd vote for a random happening as well.

Strong low frequency content will strain the power supply and the power amp, but usually the speakers are the weakest link and those start complaining or blow well before there's problems with the amp.

Regards
Sam

[Blonde Bassist]

whats the value of the fuse? I had this problem with a Hartke head a few years ago, the fuse that was fitted in the IEC cable was a 3amp fuse, which will blow if you even fart on it, changed it to 13amp fuse, and all was fine. Could be as simple as that.

[RickenBoogie]

I regularly run both bass guitar and synthesizers through my bass rig, using a switcher pedal, so one at a time. I don't think that's what hurt your amp either.

[David Smyth]

Actually I probably should have mentioned it was running off a step-down power converter (as it was brought in USA, and used in New Zealand), and maybe it's slightly more dodgy running an amp using one? probably contributed anyway..

But I got it looked at and it was apparently a 'tovoidal transformer' or something that isn't worth fixing - I dunno.. as long as my new head is sweet with the setup!

Thanks for the reponses!

[David Smyth]

Originally Posted by Blonde Bassist

whats the value of the fuse? I had this problem with a Hartke head a few years ago, the fuse that was fitted in the IEC cable was a 3amp fuse, which will blow if you even fart on it, changed it to 13amp fuse, and all was fine. Could be as simple as that.

I think it was t6.5amp slow blow/time delay or something (it was a while ago). It was the exact one that came with the amp from the factory, and it blew upon turning the amp on (don't even have to play to blow it)

[gumtownbassman]

The Head is designed for 120 volts at 60Hz, the power supply in NZ is 240 volt 50Hz. The stepdown transformer would work in most normal cases, but the supply frequency is 20% lower and may have caused transformer heating inside your amp.
In most cases also, a repeated blowing fuse (if it blows instantly and violently) maybe due to the rectifier shorted out, this is supplied directly after the trorriodal transformer.
Either way it's broken and i think 300 watts may have been a little under powered.

[David Smyth]

Originally Posted by gumtownbassman

The Head is designed for 120 volts at 60Hz, the power supply in NZ is 240 volt 50Hz. The stepdown transformer would work in most normal cases, but the supply frequency is 20% lower and may have caused transformer heating inside your amp.
In most cases also, a repeated blowing fuse (if it blows instantly and violently) maybe due to the rectifier shorted out, this is supplied directly after the trorriodal transformer.
Either way it's broken and i think 300 watts may have been a little under powered.

It did work for well over a year fine, but I was in some metal bands anyway which need more grunt to keep those guitarists at bay! I agree it's probably under-powered hence the upgrade to 750watt.

[JimmyM]

Originally Posted by David Smyth

Actually I probably should have mentioned it was running off a step-down power converter (as it was brought in USA, and used in New Zealand), and maybe it's slightly more dodgy running an amp using one? probably contributed anyway..

But I got it looked at and it was apparently a 'tovoidal transformer' or something that isn't worth fixing - I dunno.. as long as my new head is sweet with the setup!

Thanks for the reponses!

torroidial. and yeah, in that backline amp it's probably not worth fixing. trannies ain't cheap.

wouldn't blame the step down transformer, though. 4 years ago i did a 2 week tour through nz using a step down transformer for some of our gear and it was fine. i think the major problem was that you just had a bum amp. backlines are decent amps but they are budget amps and things can happen.

[David Smyth]

Originally Posted by JimmyM

torroidial. and yeah, in that backline amp it's probably not worth fixing. trannies ain't cheap.

wouldn't blame the step down transformer, though. 4 years ago i did a 2 week tour through nz using a step down transformer for some of our gear and it was fine. i think the major problem was that you just had a bum amp. backlines are decent amps but they are budget amps and things can happen.

sweet, well I'm feeling good about running this stuff through my new 1001RB, as it's obviously in a different league to the backline.

Thanks

[sleepytime]

How did you connect the mixer to the BL600?

[David Smyth]

Originally Posted by sleepytime

How did you connect the mixer to the BL600?

well that mixer has 4 mono inputs (standard 1/4 jack) and 1 mono output (standard 1/4 jack), so I just used standard instrument cables to connect from instruments, through pedals/effects, then into one of the inputs, then one to the head from the mixer output.