Question Different volume with different amps?

[cellkirk74]

Just yesterday I found out something curious about my Big Al 5 H.

It seems like for some unknown reason, the serial switching of the PU in passive mode is less loud than the parallel setting, when playing over the Mesa m6 carbine.

This is strange because with any other amp, headphones ore whatever, it is just the opposite.

Any ideas why?

 

[Golem]

`

Prolly a difference in impedence between
series and parallel. The input impedence
of various amps [pre-amp section] is not
standardized, so there's almost always a
slight/harmless mismatch. I spoze that
depending on whetherthe mismatch runs
above or below an amp's spec you could
get the result that you report.

Just guessing, acoarst ....

 

[MadMatt]

I would agree 100% percent with Golem.

The M6 is simply not compatible with your Al. I will be happy to take either one off your hands.. for a small fee of course

 

[cellkirk74]

Hey Matt,

good to know you'll help me out with that ;-)

I was surprised because it was a big volume step. At first I thought something was wrong with the Bass, but then again parallel, and both active modes were a lot louder.

Back home after practice I sat down with my tascam bass trainer to check if it was still there, but with that series mode was louder again.

Does the impendance change a lot when you change the wiring in passive mode?

It would be cool to have some inside nfo from EB on this....

 

[MadMatt]

Does the impendance change a lot when you change the wiring in passive mode?

I'm always happy to be of assistance.

My basic knowledge of electronics tells me that the Parallel DC impedance (resistance) if the HB should be 1/4 of the HB in serial mode. Bear in mind this is DC impedance... AC impedance (which is how the Bass/Amp "see" each other) is something totally different.

I believe the bass trainer had an D/A converter where as the M6 is all analog I believe. They will react differently to impedance changes.