active passive switch for musicman

[dub]

I am thinking of installing an active passive switch into my ernie ball musicman 5.

There are a few reasons for this. I would like to be able to use the pickup without the onboard preamp for a different recording tone with less noise.
I really like the tone of the mm preamp but it is quite noisy.
The preamp is on when a lead is plugged into the jack socket of the bass so I would like to be able to leave the bass plugged in while not draining the battery.

I reckon a DPDT switch with one side switching the + preamp out/pickup to volume and the other side connect/disconnect battery ground should do it.

That would leave the + signal wire from the pickup connected to the preamp input in passive mode which should be OK.

Does that sound like it would work? Does anyone have a better wiring diagram for this that takes the preamp out completely and disconnects the battery in passive mode?

Edited June 23, 2008 by dub

[dub]

I just bypassed the musicman pre-amp to see what it would sound like before installing a switch.
The surprising thing was more output with no pre-amp and no hiss at all.
The pre-amp set flat just seems to add loads of top end and hiss, so I'm just going to leave it without the pre-amp connected.
I'll have no onboard eq but the output is louder, quieter, less trebly and I won't need any batteries.

Edited June 26, 2008 by dub

[obbm]

[quote name='dub' post='227457' date='Jun 26 2008, 03:40 PM']I just bypassed the musicman pre-amp to see what it would sound like before installing a switch.
The surprising thing was more output with no pre-amp and no hiss at all.
The pre-amp set flat just seems to add loads of top end and hiss, so I'm just going to leave it without the pre-amp connected.
I'll have no onboard eq but the output is louder, quieter, less trebly and I won't need any batteries.[/quote]

Just out of interest which wire did you intercept and what coil mode is it in?

[dub]

My pickup has no dummy coil.
I disconnected the input and output of the pre-amp and connected the selector switch to the volume.

[quote name='obbm' post='227466' date='Jun 26 2008, 03:57 PM']Just out of interest which wire did you intercept and what coil mode is it in?[/quote]

Edited June 26, 2008 by dub

[obbm]

[quote name='dub' post='227520' date='Jun 26 2008, 05:11 PM']My pickup has no dummy coil.
I disconnected the input and output of the pre-amp and connected the selector switch to the volume.[/quote]


You've answered my question. Yours must be a pre-91 SR5 which has much simpler coil switching. You can't do what you've done on the later version and retain coil switching as the pre-amp has a balanced input.

[dub]

It's a pre 91 ernie ball stingray 5. I replaced the original pickup with a seymour duncan alcino copy which has much better string balance. I didn't know that about the later pre-amps, they may well have a better s/n ratio too.

[phil_the_bassist]

I've got a 2006 SR5, and want to do the same thing, purely for the sake of my wallet *WHY THE HELL ARE 9v BATTERIES SO DAMN EXPENSIVE!!!!* ahem!


Does anyone have any ideas/wiring diagrams about how this could be achieved? I don't wanna go crazy and bypass the pre-amp totally, but a switch to give me passive tone and to stop me draining the battery'd be worth its weight!

[obbm]

[quote name='phil_the_bassist' post='228359' date='Jun 27 2008, 11:09 PM']I've got a 2006 SR5, and want to do the same thing, purely for the sake of my wallet *WHY THE HELL ARE 9v BATTERIES SO DAMN EXPENSIVE!!!!* ahem!


Does anyone have any ideas/wiring diagrams about how this could be achieved? I don't wanna go crazy and bypass the pre-amp totally, but a switch to give me passive tone and to stop me draining the battery'd be worth its weight![/quote]

Firstly I don't know why you are having a problem is with batteries. Mine last for months and months.

Secondly it is very difficult to achieve what you want to do on a later SR5 because as previously mentioned the pre-amp uses a balanced input in single coil and series mode with the join of the two coils grounded. You could possibly do it in parallel mode as this only uses a single input to the pre-amp. You would of course be without any controls as the volume control is a part of the pre-amp.

[phil_the_bassist]

[quote name='obbm' post='228361' date='Jun 27 2008, 11:20 PM']Firstly I don't know why you are having a problem is with batteries. Mine last for months and months.

Secondly it is very difficult to achieve what you want to do on a later SR5 because as previously mentioned the pre-amp uses a balanced input in single coil and series mode with the join of the two coils grounded. You could possibly do it in parallel mode as this only uses a single input to the pre-amp. You would of course be without any controls as the volume control is a part of the pre-amp.[/quote]


Aah, fair enough!


I think most of my problem is the my completely, utterly and totally mortifying fear of dying in stage (battery-wise, rather than performance wise!) as it's happened once and I felt like a total pr**k!


I'm guessing a small switch between the battery and circuitry would do, just to stop any unnecessary power drainage? I'm a complete beginner when it comes to electrics, hence the stupid questions!

[obbm]

[quote name='phil_the_bassist' post='228457' date='Jun 28 2008, 10:01 AM']Aah, fair enough!


I think most of my problem is the my completely, utterly and totally mortifying fear of dying in stage (battery-wise, rather than performance wise!) as it's happened once and I felt like a total pr**k!


I'm guessing a small switch between the battery and circuitry would do, just to stop any unnecessary power drainage? I'm a complete beginner when it comes to electrics, hence the stupid questions![/quote]

I've used an SR5 for 10 years and never had a battery problem. Always get a good quality battery like a high-capacity Duracell.

Three simple tips if you are worried.

1. Always unplug your bass when not using it.

2. Check your battery voltage occasionally with a voltmeter.

2. Carry a spare battery with you. After all it only takes 30-seconds to change.

Edited June 28, 2008 by obbm

[steve-soar]

Scratch the date on the battery so you know when you last changed them. You should get at least 3 months out of a Duracell, cheap ones die within days sometimes.

[phil_the_bassist]

[quote name='obbm' post='228458' date='Jun 28 2008, 10:10 AM']1. Always unplug your bass when not using it.

2. Check your battery voltage occasionally with a voltmeter.

2. Carry a spare battery with you. After all it only takes 30-seconds to change.[/quote]

[quote name='steve-soar' post='228557' date='Jun 28 2008, 01:39 PM']Scratch the date on the battery so you know when you last changed them. You should get at least 3 months out of a Duracell, cheap ones die within days sometimes.[/quote]

I do all the above except use a voltmeter (haven't got one yet), and I've even got some highend planet waves leads with the circuitbreaker button so I can unplug without blowing eveything!

It's the only thing about playin active basses that bugs me, but it's a small price to pay I suppose!

[bassmachine2112]

hiho,2 weeks ,2months out of a battery on a mm.my mm the batteries last about 12 months n that,s giggin twice a week n 2 x 4 hour practices n doodles inbetween.i use duracell.i would suspect a problem or it,s time to invest in rechargeable ones.do ebs heads not have phantom powering for pedals n basses built in?.if any bass manufacturers want to use this simple idea,brown envelope please n a sample of wares for testing purposes will be gratefully recieved.

[dub]

You could easily use the 9V from an ebs to power your bass with a stereo jack input and a bit of soldering, but what happens when you have to go direct into a DI? Many an engineer insists on this for good reason so it is slightly problematic.

I'm still into the passive sound of my musicman, it is very different from the pre-amp tone which as far as I can hear adds about 15db of top end boost (set flat).

Since I made the change I can set most amps flat and get the sound I am after. Previously I was turning up the low end on the bass and the amp and still not getting a great tone.

I use a lot of different amps when touring and I am realizing the preset contour on many might sound good with the bass on its own but really doesn't help when the band kicks in, the mids make it much fuller and more audible on stage. I still use a bit of eq if it needs it, but only about 3db or so.

[quote name='bassmachine2112' post='280499' date='Sep 9 2008, 04:45 PM']hiho,2 weeks ,2months out of a battery on a mm.my mm the batteries last about 12 months n that,s giggin twice a week n 2 x 4 hour practices n doodles inbetween.i use duracell.i would suspect a problem or it,s time to invest in rechargeable ones.do ebs heads not have phantom powering for pedals n basses built in?.if any bass manufacturers want to use this simple idea,brown envelope please n a sample of wares for testing purposes will be gratefully recieved.[/quote]

[Cernael]

[quote name='dub' post='281032' date='Sep 10 2008, 01:25 PM']I'm still into the passive sound of my musicman, it is very different from the pre-amp tone which as far as I can hear adds about 15db of top end boost (set flat).[/quote]
Um...IMO, when you set it flat, by definition, there's no boost. It's not, perchance, that you set it in roughly the middle position? Suppose the knob really works in an "all-boost" manner; how much boost is there when you set it to 0?

Hope you don't feel insulted by this humble suggestion...

[mr_russ]

I found the same thing with the 2 SR5's I've owned - I couldn't get away with the preamp left supposedly 'flat' - I always had a ton of mid and bass boost. My lakland DJ5 however is completely passive and has way more apparent low end than even my old SR5HH.

[dub]

The treble control is a boost and cut control.

All the controls have a centre dent.

Here is a more accurate description; With all the controls centered, there is a huge top end boost from the pre-amp.

The top end is a big part of the musicman sound, so clearly Leo Fender designed the early pre-amps to sound trebly and MM manufacturers have kept that in the pre-amp design ever since.

I was just surprised that it was such a massive top end boost with the controls centered.


[quote name='Cernael' post='281039' date='Sep 10 2008, 12:41 PM']Um...IMO, when you set it flat, by definition, there's no boost. It's not, perchance, that you set it in roughly the middle position? Suppose the knob really works in an "all-boost" manner; how much boost is there when you set it to 0?

Hope you don't feel insulted by this humble suggestion... [/quote]

[Cernael]

So there is a setting that is flat, it just doesn't coincide with the centre click position?

I'm guessing that might be remedied by clever usage of resistors around the control pot...unles it's physically integrated with the preamp, so you can't get at the wires directly.

Then again, if you're happy as is, I should probably leave the horsecorpse unkicked.

[dub]

I'm really happy with the sound of the pickup and no pre-amp so if it's a horse it's very much alive.
With the top end turned down it is possible to get similar tone as the pickup on it's own, though it's still not exactly the same. I tried out a bartolini preamp in the bass once and although it was quieter I wouldn't say it was exactly flat either. All pre-amps have got a bit of a character.

[quote name='Cernael' post='282640' date='Sep 12 2008, 02:00 PM']So there is a setting that is flat, it just doesn't coincide with the centre click position?

I'm guessing that might be remedied by clever usage of resistors around the control pot...unles it's physically integrated with the preamp, so you can't get at the wires directly.

Then again, if you're happy as is, I should probably leave the horsecorpse unkicked.[/quote]

Edited September 12, 2008 by dub

[Shonks]

I have a late SR5 and installed an on/of toggle switch between the battery and Jack socket.
This way I can go on stage and leave the bass plugged in, but flip the switch off when I'm not playing.
Its like a 'standby' works brilliantly.
I tried an LED too for a while, but the battery drained to fast - looked cool though...!

[Al Heeley]

This is a good idea. Heh - funny how a little LED can drain the battery much faster than the pre-amp! Time to wedge another resistor in there, dim down that light a bit.