Jump to content
Why become a member? ×

Putting passive pickups into a bass with an active preamp??


EdLib-3
 Share

Recommended Posts

Hi all, I hope everyone is managing to keep healthy and sane during this bizarre lockdown situation. I have a used Ibanez TR200 bass from the mid 1990s on order which has PJ pickups, and the bass is active.

Here's the thing: I have a set of DiMarzio DP126 passive P J pickups (my favourites), which I would like to use to replace the stock pickups in the Ibanez when it (hopefully) arrives; however I am unsure if these can go into an active bass.

From what I can gather most active basses have passive pickups running into an active preamp but there are some examples of active basses with active pickups. My question is how do you tell if the existing pickups in the bass are active or indeed if passive pickups will work with the bass? Apologies if this is a totally dumbass question but I'm really not that up on technical side of bass hardware. Any help or advice would be most appreciated.

Cheers!

Link to comment
Share on other sites

It's most likely the TR200 pickups are passive, in which case you can replace them with any other passive pickup. If you want to run a test, disconnect one of the pickups from the preamp and connect it directly to the output jack. If you get a good strong signal then it's passive.

  • Like 1
Link to comment
Share on other sites

All pickups except for optical based systems are passive. Some with low outputs have preamps included within the pickup housing to get the level up to one that pedals and amps are happy with, but the pickup itself is passive - just some wire wrapped around a magnet.

Edited by BigRedX
Link to comment
Share on other sites

Do any production basses out there actually have active pickups? (i.e. ones with a little built-in preamp circuit, as BRX describes above)

It's something you read about, but Ive never encountered one.  Is it more of a guitar thing?

Edited by linear
Link to comment
Share on other sites

At least EMG produces pickups with built-in preamps, or rather, buffers. This way the output of the pickup is low impedance (lo Z). The basic pickup has a high impedance (hi Z) output. Impedance is the AC resistance (depends on frequency), compared to pure DC resistance. Impedance here has not very much to do with output level, although on a hi Z system the higher Z usually equals more output.

Practically any pickup can be mated with hi Z adjustments (vol, tone, blend). It is also possible to add lo Z adjustments (i.e. replace hi Z tone adjustments), which may include things like bass, treble, middle, and in some rare cases, blend and volume (check Audere and especially John East). A lo Z system needs external power, which is usually a 9 V battery or few.

So in practice nearly any preamp can be connected to you pickups. It is up to you to make the choice. An Artec costs £20 and a Sadowsky £300. Their difference is not so much in parts, but design. Preamps are based on operational amplifiers (tiny ICs) or discrete components, like transistors and FETs that consume very little power.

To modify your instrument, you need a preamp and a battery and after doing few connections, your bass has new adjustments. Check that there is enough space for all the stuff you want to add.

  • Like 2
Link to comment
Share on other sites

Big thanks for all the responses. Whilst having a look on the internet for some information on this I found a post on TalkBass where a guy discusses how he had an active Peavey Randy Jackson signature bass that he had taken into his guitar tech to have the stock pickups replaced with a passive PJ set and his tech had told him it couldn't be done as the pickups already in the bass were active.  A lot of the responses were 'all bass pickups are passive'. That's what got me thinking.

@linear EMG do a set of active PJ pickups but I notice there is a lot more in the set than just the pickups:

https://www.emgpickups.com/pjset.html

 

Once I get the bass I think I'll just run the test as @ikay suggests and see if there is a strong signal. I only want to upgrade the pickups with the ones I already have if possible, I don't want to put a new preamp in, I bought this as a back up bass and am factoring in the import taxes into the overall cost so was just planning on changing the tuners and pickups. Many thanks for all the excellent and useful responses. I'll let you know what the outcome is when the bass arrives. Cheers, Ed

Link to comment
Share on other sites

There are a lot of confusing and ambiguous descriptions surrounding pickups EQ's and pre-amps - even by the suppliers, so I'm not surprised that you are confused. 

 

But - there are, indeed, active pickups and there are also passive pickups.   Additionally there are EQ pre-amps that are designed to drive active pickups and there are EQ pre-amps that are designed to drive passive pickups.  

Here are examples of EMG active and passive pickups:

WV4NoGMl.jpg

And here is a Seymour Duncan bass EQ pre-amp designed for use with passive pickups:

eYxeBGpl.jpg

 

And here is their equivalent EQ pre-amp designed for use with active pickups:

iJwcu78l.jpg

 

I maybe wrong, but I think that 'Active' is synonymous with 'Powered'.  And I'm sure everyone will tell me I'm wrong, but I think all Active pickups require power input to drive their circuits?  

And an Active EQ preamp also requires power for its own circuitry.  That is why both of the EQ preamps above are described as Active Bass Pre-amp's, because they are both powered even though one is configured to handle passive (unpowered) pickups and the other is to handle active (powered) pickups

 

And can you have an Active pickup driven through a Passive EQ? 

Yes (think powered and non-powered rather than active and passive)  So you can put active (powered) pickups, that will require a 9v feed, and send their output through standard tone pot circuits (although the values may be different), which are passive (unpowered).

And finally - because it took me a long time to understand this - what's the difference between an Active EQ and a Passive EQ (such as a conventional tone pot & capacitor arrangement):

It is simply that the passive arrangement can only CUT frequencies.  So it gives bass by cutting out some of the treble.

But a powered (active) EQ can BOOST the bass frequencies and/or the treble frequencies as well as cut them.

 

Leastways, that's how I have kept my sanity over the years trying to get the right bits for the right things.... ;)

 

 

 

 

  • Like 3
Link to comment
Share on other sites

4 hours ago, Andyjr1515 said:

There are a lot of confusing and ambiguous descriptions surrounding pickups EQ's and pre-amps - even by the suppliers, so I'm not surprised that you are confused. 

 

But - there are, indeed, active pickups and there are also passive pickups.   Additionally there are EQ pre-amps that are designed to drive active pickups and there are EQ pre-amps that are designed to drive passive pickups.  

Here are examples of EMG active and passive pickups:

WV4NoGMl.jpg

And here is a Seymour Duncan bass EQ pre-amp designed for use with passive pickups:

eYxeBGpl.jpg

 

And here is their equivalent EQ pre-amp designed for use with active pickups:

iJwcu78l.jpg

 

I maybe wrong, but I think that 'Active' is synonymous with 'Powered'.  And I'm sure everyone will tell me I'm wrong, but I think all Active pickups require power input to drive their circuits?  

And an Active EQ preamp also requires power for its own circuitry.  That is why both of the EQ preamps above are described as Active Bass Pre-amp's, because they are both powered even though one is configured to handle passive (unpowered) pickups and the other is to handle active (powered) pickups

 

And can you have an Active pickup driven through a Passive EQ? 

Yes (think powered and non-powered rather than active and passive)  So you can put active (powered) pickups, that will require a 9v feed, and send their output through standard tone pot circuits (although the values may be different), which are passive (unpowered).

And finally - because it took me a long time to understand this - what's the difference between an Active EQ and a Passive EQ (such as a conventional tone pot & capacitor arrangement):

It is simply that the passive arrangement can only CUT frequencies.  So it gives bass by cutting out some of the treble.

But a powered (active) EQ can BOOST the bass frequencies and/or the treble frequencies as well as cut them.

 

Leastways, that's how I have kept my sanity over the years trying to get the right bits for the right things.... ;)

 

 

 

 

Awesomely helpful! Thanks so much. Damn I love Basschat!

  • Like 1
Link to comment
Share on other sites

Strictly speaking the EMGs are not active. True there is some battery driven circuitry inside the housing, but it doesn't have anything to do with the actual pick-up which is still conventional wire wrapped around a magnet. What it is there for is to match the output/impedance of the pickup to values that the rest of the signal chain would normally expect.

  • Like 2
Link to comment
Share on other sites

33 minutes ago, BigRedX said:

Strictly speaking the EMGs are not active. True there is some battery driven circuitry inside the housing, but it doesn't have anything to do with the actual pick-up which is still conventional wire wrapped around a magnet. What it is there for is to match the output/impedance of the pickup to values that the rest of the signal chain would normally expect.

True...and that's why I personally prefer to refer to them as powered or unpowered. 

Unfortunately, all the manufacturers I know of refer to them as active or passive, not just EMG. 

  • Like 1
Link to comment
Share on other sites

2 minutes ago, Andyjr1515 said:

True...and that's why I personally prefer to refer to them as powered or unpowered. 

Unfortunately, all the manufacturers I know of refer to them as active or passive, not just EMG. 

Again true, But the actual pickup mechanism isn't powered. It's the additional circuitry that is required to match the output/impedance of the pickup to conventional guitar and bass impedance and output levels. EMG (and others) could just as easily sell these pickups without the additional powered circuitry with the proviso that they need to be used with a particular pre-amp that has the correct input specifications.

  • Like 1
Link to comment
Share on other sites

6 minutes ago, BigRedX said:

Again true, But the actual pickup mechanism isn't powered. It's the additional circuitry that is required to match the output/impedance of the pickup to conventional guitar and bass impedance and output levels. EMG (and others) could just as easily sell these pickups without the additional powered circuitry with the proviso that they need to be used with a particular pre-amp that has the correct input specifications.

They could do but it is probably not worth their time dealing with people who couldn't read.

My NS Stick does have active EMGs in it, although that is probably because they are telecater pickups originally.

Link to comment
Share on other sites

33 minutes ago, BigRedX said:

EMG (and others) could just as easily sell these pickups without the additional powered circuitry with the proviso that they need to be used with a particular pre-amp that has the correct input specifications.

Particular and particular. Modern preamps have so high input impedance that they eat nearly anything from piezo to buffered lo Z pickups. Sounds a bit like marketing to separate the preamps to "active" and "passive" versions. If the preamp has output level trimmer glued to the side, it certainly works for both impedances. Even if it did not have the trimmer.

Shame on you Seymour Duncan.

Edited by itu
  • Like 1
Link to comment
Share on other sites

On 30/03/2020 at 00:00, hooky_lowdown said:

Passive pickups with an active eq are low output, as the eq generates extra output. The DiMarzio pups maybe too hot and as a result, in combination with the eq will make the pups sound distorted, same as if you raise pickups close to the strings the sound gets distorted.

 

Not in my experience.

Passive pickups in every bass I have encountered with active EQ are just standard passive pickups that work just fine with a passive tone circuit, or nothing at all if that's what one wants. The preamps on these basses *can* boost the signal a lot if the controls are set to boost, but generally they're pretty reasonable and compatible with everything else (what would be the point of making something that only works with a few pickups). Some even contain internal trim pots to set the basic level.

Active pickups, however, are extremely low output until they're amplified by their built-in preamp, which is why you may get some signal out of some active pickups, but too low to be usable.

OP: The DP126 set (Model P and bridge of Model J set) are pretty hot pickups, but not crazy. I don't have a lot experience with adding preamps to these, I only added a John East MMSR preamp (designed for Stingrays) to a Model P in a Precision and it worked beautifully. I don't see a reason why the DP126 won't work on yours.

The DP126 pickups are a bit thicker than most standard PJ pickups, which may or not be an issue on your bass. If it's got a thin body (I am not familiar with your TR200, I've only played SR series ones, which were a little thin) you may not have a lot of room to adjust the pickup heights. Still, all this is easy to try and if it doesn't work, all you've lost is some time, as it's fully reversible.

 

  • Like 1
Link to comment
Share on other sites

On 31/03/2020 at 11:40, Andyjr1515 said:

True...and that's why I personally prefer to refer to them as powered or unpowered. 

Unfortunately, all the manufacturers I know of refer to them as active or passive, not just EMG. 

 

Indeed. It's like Fender calling the tremolo effect in their old amps "vibrato" and calling the vibrato system on their Stratocaster guitars a "tremolo"... in the end you have to follow the common nomenclature even if they're wrong.

  • Like 1
Link to comment
Share on other sites

Once again I am super grateful for the knowledge imparted here. As a result of people's input on this I am feeling pretty hopeful about the DiMarzio PJs going into the bass without any problems. I haven't yet received the bass in question, it's still slowly making its way to me. At the moment I have absolutely no idea when I'll be able to get the pickups fitted to this Ibanez TR200, as there are no guitar shops open to do the work.

I'll send an update with photos to let you know the outcome of this...eventually 😁

  • Like 3
Link to comment
Share on other sites

14 hours ago, EdLib-3 said:

Once again I am super grateful for the knowledge imparted here. As a result of people's input on this I am feeling pretty hopeful about the DiMarzio PJs going into the bass without any problems. I haven't yet received the bass in question, it's still slowly making its way to me. At the moment I have absolutely no idea when I'll be able to get the pickups fitted to this Ibanez TR200, as there are no guitar shops open to do the work.

I'll send an update with photos to let you know the outcome of this...eventually 😁

 

Not sure if this would work, but you may ask in the forum for anyone local to you who is proficient and likes doing this kind of work. It's pretty easy, if you know what you're doing... who knows, maybe you find someone who would love a chance to look away from Netflix for a bit and help you in the process if you are able to drop the bass with them. Of course it's a bit more complicated now with the distancing etc, but doable if you're sensible.

Just an idea.

Link to comment
Share on other sites

  • 5 weeks later...

Update: here's the bass in question; it turned up in very good condition and plays very nicely. It's currently having the work done for the mods so this is a 'before' pic. I'll post a better picture (backlit..never good) when the new DiMarzio pickups, Schaller machine heads and strap locks have been fitted. I decided against replacing the stock bridge as it's a pretty decent high mass bridge, I'm really looking forward to ditching those tuners though, they're totally wrong for that headstock and in general an absolute travesty!

IMG_1938.thumb.JPG.0fa8303adc246b803bd5721cd180db28.JPG

  • Like 1
Link to comment
Share on other sites

  • 2 weeks later...

Allow me to resurrect this topic with a final update, here's the bass with all the mods completed:

IMG_1996.thumb.JPG.c2d29eeb1f62c60c48d9aa7822d70e36.JPG

The DiMarzio passive pickups went in fine with the bass's active preamp and sound excellent, many thanks for the advice!!

I also had some Gotoh tuners fitted to replace the stock ones after the Schallers I bought were too wide in the backplate to fit the headstock. Lastly, strap locks fitted and I did a u-turn and decided to change the stock bridge to a beefy Kluson high mass bridge after all . Plays and sounds way, way better. No longer such an inexpensive bass now... 😬

IMG_1995.thumb.JPG.06dc49be7959e408432e0e19200d8394.JPG

  • Like 3
Link to comment
Share on other sites

  • 5 months later...
4 hours ago, All-X said:

Hi, I have the same set of pickups, with an Aguilar OBP3 Aguilar preamp, however I experience a great loss of  punch in the sound, I really get more punch connecting the trucks in  passively mode.  What preamp do you use?

Hi @All-X mate, I didn't change the preamp; just pickups, bridge and tuners. I drew the line at the preamp as I'd already sunk enough cash into this what with import tax and the like. My DiMarzios sound very balanced and responsive through what is an inexpensive preamp as this bass wasn't top of the TR range when available new back in '97. I can't give you any information about the stock preamp, all the mods were done by my local guitar shop. I should point out that I had the exact same set of pickups in an Aerodyne Jazz I used to own and have never experienced the problem you describe.

Edited by EdLib-3
Typo
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...