Will a buffer pre-amp solve my problem?

JDM,
You didn't mention in you're profile what kind of pickup you are using.
I can't really help you that much unless you post what kind of pickup it is.


Ric

 

Yeh,
Did I miss something or did the bass players of the world rebel
all and start building their own pickups? JDM, I'm suprized that you didn't go ahead and built you're own buffer preamp. The Fishman Pro Platinum is a very nice unit, unless you can afford a used Acoustic Image Clarius.


Ric

 

Yeah, look at my DIY preamp thread. But I would not worry too much about the commercial pickup / preamp market. It's hard to save money unless you are already equipped with all of the tools, and can afford the time. For most of us DIY'ers, building gear is still mainly a hobby, and we end up buying commercial gear in addition to our homemade stuff. I do it because I enjoy learning more about electronics.

For my preamp designs:

www.execpc.com/~fdeck/bass

 

Fdeck,
Gone are the days when I attempted to build a pair of Knight Kit Walkie Talkies from Allied Radio. I learned enough from that experience to know better when not to get out my trusty soldering iron.
From my perspective, you and Tone Ranger should get together and form startup up company. When you guys post how to build a pickup and
your little pre amplifier, it's like a breath of fresh air to me. After all,
it's not about how expensive you can build something, it's about how well it works. I think you guys should be doing the reviews for some of the commercial bass magazines, instead of the advertisers. Just a thought!

Ric

 

Funny you should mention it...

www.execpc.com/~fdeck/meld

It's not bass gear, but I do enjoy the hobby of running a microscopic electronics business. You can see that I even stole the idea from Acoustic Image of basically going out of business while I design my new product. I admire their integrity, because it eliminates the problem of the pissed-off customer who buys the old model one day before the new model is announced.

I would love to do that. Indeed, I have developed some techniques for measuring the performance of bass amps with very little equipment, and one of these days, I might write an article sharing my ideas.

For me, there is another aspect, which is knowing in detail how gear really works. It allows me to be a much more informed consumer when I actually go out and buy real gear, which I might do someday if my gig schedule ever fills up again

 

JDM - I''m going to add my vote to the "probably no up quick fix" camp. But I'm definitely all for your keeping the DIY experiments. The fact is that it is hard to amplify any acoustic intrument and the bass is one of the hardest. Recording studios will often employ thousands of dollars of mics and preamp. There are lots of "reliable" live rigs but all have drawbacks. And all take a lot of tweaking between pickup, preamp and amp. I don't know anyone who thinks that the sound of their acoustic intstrument is identical to its amplified sound. At some point people declare themselves "done" but it's never perfect.

 

I have a Radio Shack piezo on my DB. It was cobbled up by a decent luthier, so it's not really DIY- but it only cost $50. It also sounded thin, etc; running through a K&K Pure preamp helped, but the best sound I've gotten out of it yet has been when going straight- as in bypassing the pre- into an Eden CXC-110 combo(I've just recently seen an equally unfavorable opinion on Eden in general for DB, so go figure). Before that I used a Hartke Kickback 12 w/fairly good results- I really like the 'shape' function for dialing out feedback-prone frequencies. My guess is that there is a preamp/amp/cab combination that will not neccesarily sound 'just like your bass only louder', but work best for you & your gig.

Edit: After reading the original post again, I thought I'd mention I use my CXC for doubling- for BG, I add a CX-110 extension cab(giving me [email protected]); for DB I use just the combo(180 [email protected]). IME, more or bigger speakers can induce feedback problems.

 

If I was a smarter business man, having found out how to make a good sounding pickup very cheaply I should have come up with a catchy brand name, printed some classy packaging, and put them on the market just a bit cheaper than all the opposition. However, my day job is as a classroom teacher, so I can't resist the urge to pass on information for free! Also, there's a lot of hype in the music business - I appreciate the chance to cut through some of it and say, "Look, this aint rocket science - make your own pickup, solder your own leads, adjust your own bridge, and send the money you save to an orphanage in Uganda where they can really use it!"

 

Hi Jon. I could be all wet, but I don't think a buffer preamp is the answer here my friend. I would try a different pickup if I were in your shoes.

I have experience with the K&K Bass Max and the Revolution SOLO. Both of these pickups are affordable (DIY is not one of my areas of expertise), easy to install, and neither requires a preamp.

(I should say many people do use a preamp with these p/u's, but strictly speaking I don't think you have to. Lots of folks like these pickups w/out a preamp.)

bassteban's suggestion is a good one, and is worth trying. You might want to try bypassing the front end of your Hartke and send the pickup straight into the effects return, and see if you like how it sounds.

 

Well, what do you know so am I, Although after retire in two more years
it's back to music full time!!!!

Agreed, and what is probably more important, it allows students who can't
afford the commercial products, a chance to have a decent pickup for their
instrument. To me , you've filled a real need because gear today is pretty expensive. Especially, a good instrument.


Ric

 

You couldn't be more on target. I guess it's my 60's sensibilities coming out, but I think that the concept of "planned obsolescence" hurt the music
industry more than it helped. They have "redesigned so many bass amplifiers to "improve them" and most times they compromise what was good in the first place.

This benefits all bass players, since you are creating what I would consider to be a valuable kind of consumer reports for bass gear.

Ric

 

Well, it's not clear. I don't know the input impedance of the Hartke but you may already know that piezos should look into Hi-Z inputs (at least 1 M-ohm). If your input does not qualify, then an outboard pre-amp will be desirable regardless of the piezo pickup you use.

With regard to DIY piezos, IMHO, this is a case where the DIY approach is simply not time- and cost-effective. Upton sells the RS for $99. They've done tons of tweaking and experimenting and it's a fine pickup. I've never needed a pre-amp with the RS so long as the amp I used had the requisite high Hi-Z input.

Just my $0.02.

 

On the original question of 'Do I need a preamp', I think the main issue is the output of the pickup. In my experience, a piezo that sits under the bridge has a lot more pressure driving it, so a lot more output, than one that clips on or slides into the bridge wing.
Theoretically a piezo should have a buffering preamp but if it has plenty of grunt to start with that's not so important.

I beg to politely disagree. In my country (Australia) pickups are rare and expensive. I've never seen one in a music store - they're always special order. Most players I know use Fishmans and struggle to get a sound. A friend has a Realist that cost over $400 AU but it's cracked and picks up radio.
My home-made pickups ( www.fittell.id.au/piezo ) take about 15 minutes to assemble and parts cost less than $5.
All reports indicate that the RS is a good product at a good price (I've not seen one) but for me, the DIY appraoch was much more time- and cost-effective.

 

Well, I see no reason why theoretically a piezo should have a buffering pre-amp if the pre-amp section of the amp you are using is designed to provide a proper load for a piezo. I suspect we do not really disagree here.

Fair enough. I should have said that, for most, it is not time- and cost-effective. Of course, what matters is the sound. More power to you if yours sounds anything like an RS!

 

Here's a different solution for you...I have three different bass amp rigs: an Acoustic Image Contra that has a proper 10 Mohm input impedance for piezo pickups (I've got a Fishman Full Circle), and two other rigs (David Eden, Gallien-Krueger) that have only low impedance inputs. While I usually use an older Raven Labs pre-amp with those guys, I'm in love these days with an Aphex Acoustic Exciter stomp box. This little green fella uses Aphex's "aural exciter" technology on higher frequencies and their "big bottom" technology on lower frequencies. Tune it up just right and it gives a completely remarkable warmth and perceived greater harmonic content to notes. One band leader with whom I've worked (he began as a bassist) described the effect as "beguiling". But, to the point...the pedal has two impedance settings. The "passive" setting is 10 Mohms in and will alone dramatically warm a piezo pickup when used with a low impedance bass guitar rig. Don't put it in the effects loop, but between the instrument and the amp input. You not only get the an impedance fix, but this *lovely* warmth.

Mike Lee

 

Hey Mike, I think I'll have to get out my Acoustic Xciter pedal and check this out!

I tried using it w/ my upright a year or two ago when I bought it, but I thought I could detect "artifacts" in the sound even when it was supposed to be running flat ("Lo Tune" set to 0 and "Hi Tune" set to 10) and even in direct bypass mode (foot toggle switch in "off" position).

I was (and still am) looking for as pure of a sound as possible for most situations, so didn't like these slight artifacts.

I think it kinda wigged out too when I sent a blended signal from a pickup and a mic into it. Did wierd things to the 'mic' part of the signal in particular, and sounded better with just the pickup I think.

But the "Big Bottom" effect was pretty intriguing all right. Pretty much works as advertised.

I didn't notice the 10M-Ohm input until you pointed it out. Maybe I'll dig the funky green box back out and try it again ...

P.S. I enjoyed visiting Halifax this summer. Cool city!

 

+1

I've been messing with different sensors, packaging, and placement for a while now. I've found that placement is everything. From the picture, I'm guessing that the piezos are not making solid enough contact to put out a decent signal. Gently wedging them under the bridge wings should give you a much fuller sound. Not too much, if they're firmly jammed in it seems to choke off everything but the mids and sounds almost honk-y. Even the exact position the wings make contact will affect the sound.

Under the bridge itself is good, too, but I'm loathe to do that personally because my soundpost tends to fall over if I sneeze too hard while the bridge is off. I've had zero complaints about my bass tone going into darn near any amp with various DIY pickup designs.

And I still haven't spent as much money as I would've after buying Fishman's lowest priced model.