Is there really any difference in volume between active & passive?

[Happy Jack]

When I ordered my Status Streamline I specified the addition of an On/Off switch for the active circuitry. I genuinely prefer the sound of that particular bass in passive mode for certain songs and styles of music, but it also means that battery failure during a gig would not prevent me from playing.

On a related note, both my Wals are always-on active basses. At rehearsal last week, my 5-string packed up with what sounded like an input-socket problem. Messed about with it over the weekend, nowt wrong with the input socket or the lead I was using. Hmmmmm. Eventually tested the battery ... utterly, utterly dead and it had the same effect as a failed input socket.

Replaced the battery.

Yesterday I came across the on-board wiring guide for the bass and realised that I had the trim-pot for Master Volume set quite low. Opened up the bass and re-set it to 'max', as recommended.

Plugged in, and got the same problem as previously - dodgy input socket. Hmmmm. Opened it up, no problem. Battery drain? Checked - no problem. Hmmmm.

The only other thing it could be was the Master Volume trim pot, so I set it to 'min' instead of 'max'. And the bass worked perfectly and sounded great. The pot had been wired the wrong way round.

There are times when passive seems to be the only way ...

Edited April 19, 2012 by Happy Jack

[stingrayPete1977]

In reality the difference in Db from active to passive is neither here nor there compared to the available Db boost from something like a 600w bass rig, dont worry about it

[Jono Bolton]

[quote name='LowdownRumble' timestamp='1334776604' post='1621200']
Mine isn't any louder than my old passive bass was. And the change of batteries is pissing me off and I hate that I cant leave it plugged in. Is there such a thing as an active/passive bass? Such as, when the battery dies switch to passive and rock on?
[/quote]

The Fender Marcus Miller Jazz has a active/passive switch, it may just have been the way I had the EQ set but I noticed a big increase in volume when going from passive to active. If you can switch between the two then I believe it's usually passive pickups, with an active EQ, that was certainly the case with the MM.

[leftybassman392]

I don't think anybody's mentioned pickup height yet, which can have a dramatic effect on output level.

I think it's the case though that for any given instrument and setup, you should normally expect more output from an active circuit than a passive one (passive circuits are subtractive and cannot add voltage whereas active circuits have an additional power source that can be used to boost the signal level). I'm no expert in this kind of thing, but I'm pretty sure there's plenty of power available to run the active eq with plenty to spare for signal boost.

[xgsjx]

Having looked at some schematics, I found that Fender appear to use 250k pots for passive & 100k pots for active (all they do is tap a 9v battery into the signal).

I've kept my pick ups at the same height as they was when it had active circuits. It's actually working better with the moog stuff! I wish it woulda broke 2 years ago!!!

[daz]

I have a Farida PB 18 (passive), and it sounds an [i]order of magnitude[/i] louder than any other passive bass i own. No idea why ? So it really does differ from one model to the next, and maybe even one batch to the next ? If i plugged this into my Hartke LH500 and turned everything up to eleven, I think it would literally wake the dead, as well as offing me, in the process, as I play whilst sitting on a stool right in front of the cab

I[i] never[/i] play louder than '2' when using that bass. .

Edited April 19, 2012 by daz

[leftybassman392]

Yup, I'd agree with all of that. Posters had discussed some apparent anomalies as between active and passive. I just decided to point out an aspect that nobody had yet raised.

I have some knowledge of pickup types and characteristics and I'm familiar with the principles of electromagnetic induction - which is why I suggested that in otherwise identical instruments most people would, I suspect, feel entitled to expect higher output from an active circuit even with the eq set flat. Otherwise why are we all having this discussion?

[leftybassman392]

I get the feeling that amp makers have started to realise this and are moving away from that design philosophy (TC Electronic and GenzBenz being cases in point).

[xgsjx]

[quote name='leftybassman392' timestamp='1334905115' post='1623128']
I get the feeling that amp makers have started to realise this and are moving away from that design philosophy (TC Electronic and GenzBenz being cases in point).
[/quote]

One company who might have labelled their inputs more accordingly was Carlsbro. On my old Cobra head it said "Low Gain" & "High Gain" as opposed to the usual "Passive" & "Active".

[leftybassman392]

[quote name='xgsjx' timestamp='1334923896' post='1623506']
One company who might have labelled their inputs more accordingly was Carlsbro. On my old Cobra head it said "Low Gain" & "High Gain" as opposed to the usual "Passive" & "Active".
[/quote]

I've got that on my Cornford guitar amp. I just plug everything into the high gain on the grounds that more is better!

[BigRedX]

When you get amp inputs that say Hi and Lo do they mean high and low gain or that they are for high or low output basses?

[leftybassman392]

[quote name='BigRedX' timestamp='1334925853' post='1623561']
When you get amp inputs that say Hi and Lo do they mean high and low gain or that they are for high or low output basses?
[/quote]

Good question! I've seen examples of both before now. Easiest way to find out is to plug into both alternately without touching the volume on the bass and see which one is louder. That will be the high gain input - for low output basses...

Edited April 20, 2012 by leftybassman392

[TimR]

Without getting too technical. The active preamp provides what is called a buffer between the cable and the pickups. The impedance of the pickups vary with frequency and higher frequencies can be dulled. The preamp provides a constant load to your amplifier.

It may sound the same volume but might not sound the same tonally.

[yorks5stringer]

[quote name='xgsjx' timestamp='1334923896' post='1623506']
One company who might have labelled their inputs more accordingly was Carlsbro. On my old Cobra head it said "Low Gain" & "High Gain" as opposed to the usual "Passive" & "Active".
[/quote]

I have mine labelled "passive" and "aggressive".................

[mcnach]

[quote name='LowdownRumble' timestamp='1334776604' post='1621200']
Mine isn't any louder than my old passive bass was. And the change of batteries is pissing me off and I hate that I cant leave it plugged in. Is there such a thing as an active/passive bass? Such as, when the battery dies switch to passive and rock on?
[/quote]

The John East P-Retro preamp does that.
Alternatively many have a bypass switch that allows you to bypass the preamp entirely. Some even have a passive tone control too (Glockenklang comes to mind)

But I never understood how people have problems with batteries in active basses (I know, I know, we're all different, I'm not judging you, just saying I cannot understand it).
Batteries last a long time and are cheap...


Whether passive or active, I think it's a good habit to unplug the bass. If you leave it plugged, it's just a matter of time someone will trip on the cable. The result could be a lucky escape, or a damaged cable/jack socket, or your bass falling face first on the ground...

[mcnach]

[quote name='leftybassman392' timestamp='1334854544' post='1622459']
I don't think anybody's mentioned pickup height yet, which can have a dramatic effect on output level.

I think it's the case though that for any given instrument and setup, you should normally expect more output from an active circuit than a passive one (passive circuits are subtractive and cannot add voltage whereas active circuits have an additional power source that can be used to boost the signal level). I'm no expert in this kind of thing, but I'm pretty sure there's plenty of power available to run the active eq with plenty to spare for signal boost.
[/quote]

Active EQ can boost or subtract, while passive tone controls only subtract signal, you are right. But a "flat" preamp does not necessarily boost the level. It can, and some really do. Some have a trim pot that allows you to set the signal, so you can truly balance the sugnal, and make it even quieter, when flat, if you wanted to.
You can't generalise. Active = louder is a misconception perpetuated by people seeing amps with two inputs, labelled "active / passive" when they should really say "high / low". My G&L L2000 in passive mode produces a higher output than any active bass I have ever owned, for example.

Edited April 20, 2012 by mcnach

[Wylie]

[quote name='stingrayPete1977' timestamp='1334778164' post='1621239']
I run nothing passive and whenever anyone uses my rig with a passive bass they need to boost the output volume loads, that's why lots of amps have either a passive/active switch or separate inputs surely?
[/quote]

Yes.

[discreet]

[quote name='yorks5stringer' timestamp='1334962571' post='1624262']
I have mine labelled "passive" and "aggressive"...
[/quote]

[LowdownRumble]

[quote name='mcnach' timestamp='1334963010' post='1624268']
The John East P-Retro preamp does that.
Alternatively many have a bypass switch that allows you to bypass the preamp entirely. Some even have a passive tone control too (Glockenklang comes to mind)

But I never understood how people have problems with batteries in active basses (I know, I know, we're all different, I'm not judging you, just saying I cannot understand it).
Batteries last a long time and are cheap...


Whether passive or active, I think it's a good habit to unplug the bass. If you leave it plugged, it's just a matter of time someone will trip on the cable. The result could be a lucky escape, or a damaged cable/jack socket, or your bass falling face first on the ground...
[/quote]

No offence taken, but it is a pain for me as the battery compartment lid on my bass has a dodgy release latch. It takes me at least 5 minutes just to get the thing off. Also, there is no issue of anyone tripping over the cable because my bass is in a corner and no one walks within 4 feet of it.

[mcnach]

[quote name='LowdownRumble' timestamp='1335196063' post='1627046']
No offence taken, but it is a pain for me as the battery compartment lid on my bass has a dodgy release latch. It takes me at least 5 minutes just to get the thing off. Also, there is no issue of anyone tripping over the cable because my bass is in a corner and no one walks within 4 feet of it.
[/quote]

Like I said, we all find a way that suits us personally...

Battery compartment... I've been there. My SUB has a particularly bad latch... but I have only needed to open it once, and I am not planning to do it again until June, I'm sure I will find some quiet time).
In a couple of basses I need to undo several screws to access the battery, so I also need a suitable screw driver. I guess I'm paranoid enough to replace the batteries before they show signs of failure (some preamps let you know, through distortion or other noises, that they're low in juice, I tend to replace them every 6 months or so in my gigging basses... I'm sure they'd last easily another 6 months, but if peace of mind costs me £3, I think that's alright)

As for leaving the bass in a corner and nobody approaching it. It is probably so most of teh times. But one day, somewhere, someone might just not pay attention. Again, I suppose I am paranoid enough to not want to take the risk... or put in other words: I never underestimate the stupidity (some say carelessness, I don't) of the people around me, well meaning as they may be. [1]

May your bass live a really long life.

[1] and I am not necessarily above anybody else. I used to tell the singer in this one band not to leave his pints (he'd get a couple, someone else will buy him one more... and he'd accumulate them) in such place where he has to reach over my pedal board everytime he wants to take a swig. Eventually I trained him. It happened teh day I told him not to leave the drinks over that PA sub, becaus ethe vibrations may make teh glasses fall on my board. He moved them. But... erm... I still left mine while I was setting up stuff.. and sure enough, I dropped my G&T over my board. My board worked fine, it was just sticky... but I was able to look at him and say "see what happens? if that was you I'd kill you!". We laughed about it and we both try to be a bit more careful now... but I'm sure I will still show my human nature and do something stupid again at some point.

Edited April 23, 2012 by mcnach

[jaydentaku]

The 18v circuit on my Peavey Cirrus makes one hell of difference! I never have it passed half way. If I find I am getting lost in the noise, it does help, even turning it up 5.

[Prime_BASS]

[quote name='stingrayPete1977' timestamp='1334778164' post='1621239']
I run nothing passive and whenever anyone uses my rig with a passive bass they need to boost the output volume loads, that's why lots of amps have either a passive/active switch or separate inputs surely?
[/quote]

A lot of active basses I've used in the past have all been a lot less hotter than all the passive basses I've used, bar the jaguar whose active sound is a lot louder than the passive.

Loudness from the majority of basses is determined by the amount of coils around teh magnet. More wire wraps gives you more outout, and less gives you less output, but a high fidelity sound, such as EMG's who power the pickups with batteries. There is also a difference between active pickups and active preamps.

My sterling barely clip's the Markbass until it's nearly reaching half way on the gain knob, but I don't use a lot of actual low end bass, the preamp's bass knob is not even half way round (John East MMSR) while boosting it will cause the amp to clip more but not sound much louder.

[BigRedX]

[quote name='Prime_BASS' timestamp='1335206324' post='1627316']
Loudness from the majority of basses is determined by the amount of coils around teh magnet. More wire wraps gives you more outout, and less gives you less output, but a high fidelity sound, such as EMG's who power the pickups with batteries. There is also a difference between active pickups and active preamps.
[/quote]

Is there? Does anyone know what's inside an active EMG pickup? Is it simply a standard pickup plus a pre-amp or is there something more to it?

[Prime_BASS]

[quote name='BigRedX' timestamp='1335206651' post='1627324']
Is there? Does anyone know what's inside an active EMG pickup? Is it simply a standard pickup plus a pre-amp or is there something more to it?
[/quote]

I guess I should have been more specific, like the JVX, powered by 9volts and will go into a passive preamp, but still will sound just as loud as any other passive or active pickup/preamp.

[TRBboy]

[quote name='LowdownRumble' timestamp='1335196063' post='1627046']
No offence taken, but it is a pain for me as the battery compartment lid on my bass has a dodgy release latch. It takes me at least 5 minutes just to get the thing off. Also, there is no issue of anyone tripping over the cable because my bass is in a corner and no one walks within 4 feet of it.
[/quote]

Is it not worth buying a new battery compartment for a few quid to save you struggling with it?