Double Bass Wishlist for URB Piezo preamp

[flatback]

I've said it before on these pages and I'll say it again here just for clarification lest any high falutin "shut up and play the bass and never mind about the pickup or preamp you shouldn't need one anyway it should all be in your hands" people want to chime in...
I personally have a real affinity for those non playing or hobbyist bassists or luthiers who invent shite that makes my job and life easier and better sounding.The guys at ToneDexter are a great example. So is Andrea Spada who made my travel bass, so is Kiyohiko who makes the Yamahiko, and the cats who make the Felix and the Headway guy in the UK and Mike Arnopol with the MAS gear and a whole host of other inventor cats who are trying to make my life as an upright bassist easier and better sounding. I like seeking them out and supporting their efforts. I like talking about them here at TB so that a wider audience can dig on what they have to offer. Some stuff does not work out, some gear leads to other gear, some of it is just brilliant: MAS speakers, Ischell mics, etc. Stuff that really makes a difference in your job.
Harun from Turkey is sending me a Paradox preamp to review. Man this cat has put some work into designing and hand building a preamp and has thought about all the things he thinks needs to go into it to make it useful to musicians. I sure dig that. I like that he does not say "hey the Felix is out there why would I bother?" No he makes HIS preamp and believes in it.
So when I put up this thread it is in that spirit: There is a need for a bass preamp specifically engineered to address the needs of upright players using a piezo. What should be in it? MAybe someone like Harun in a custom shop will have the inclination to build the perfect preamp, and then offer it up for sale to those people interested in having it.
I love James at ToneDexter because in the face of all these bass players saying, "naw, that aint gunna work" or "well it aint perfect" He says "hey how can I make it better for you? How can I adjust to what you want and earn your dollar? Honestly and with a product that I believe in (that may or may not be right for you)
But this IS TALKbass. It is the only place (here in this little secluded cornerickups and amps on an obscure subheading of a much bigger electric bass page to actually let this info get a hearing.
Seriously I really appreciate inventors. I love what they do. My dad bought one of the first Axys aluminum drum pedals 30 years ago not because it was the most brilliant thing ever but because it had promise and some cat really believed in it and he supported that.
SO I know that if you look up my history here you will see an enthusiast who has supported a lot of new products. I have started threads about a bunch of products that went on to sell big and a bunch that no one ever heard of again. I dont make any money on it at all. I play $100 gigs for a living playing jazz which I love more then anything (sept my family)
In all the time I've been playing it has been the small shop inventors who come up with the killing products.
That is what I am hoping for here: a bunch of bassists who use piezos to really zero in on what would be ideal in a preamp for this very specific purpose and then to see if we can get it made.

 

[Povl Carstensen]

I would love to see a preamp with an average EQ section, along with some common preset modeling. The Tone Dexter guys pretty well ignored me when I brought it up, but I think it would be awesome to have presets with stuff like: Vintage Kay w/guts, Carved German w/Steels, etc., etc., etc. Like go ahead and pick 6 very common, desirable upright bass tones and have a pro do your modeling training. Like @flatback said, I just want to plug in and find a decent tone quickly - with any preamp

I do not think it would work, not always anyway. Because the pickup signal is integral to the generation of the wavemap, so your pickup/bass signal being different than the one used for the presets will change the result.

 

[Jon Mush]

I’ll jump in then. My perfect preamp includes:
1) Great hi/lo eq shelving points, and an actual parametric mid (the sweepable ones often have a bandwidth that doesn’t suit the situation).
2) Boost with variable level
3) Built in Tuner
4) Mute
5) a defeatable, mixable Wavemap/IR filter DSP that affects the piezo to sound more microphone-like
6) Input Level control with metering
7) A defeatable FX loop.
8) No compromise on power supply/internals to make it as high end (sonically) as possible. Internal 120v would be great.
9) DI output (with polarity invert)
10) Separate amp output (1/4”)
11) upgradable firmware

There may be more...but those are the hot buttons now.

 

[Eric Hochberg]

Just curious, as many complain about piezo pickups and find a need to tweak their output with various devices to make up for shortcomings, why aren't non-piezo pickups taken more seriously, such as the Stat-B?

I've had years of experience with Underwood, Realist, Full Circle, Lifeline and others and always go back to my Stat B. @flatback, you sometimes use a Stat, no? What do people like about their piezos that keeps them using them when there are other, better (to me anyway) options?

So as not to derail, I just created a new thread on this topic...

 

[flatback]

One of the reasons i am interested in the piezo thing right now is I just got a new bridge wirh the Yamahiko for my contrabassetto. I have been having a hard time finding the right pickup ( bridge pickups are too brittle sounding etc)
In rhe past few days i have been finding what sounds best and yesterday i mixed rhe Stat B and Y ( just the E side for both) and got the best sound so far ( the Remic sounds really rhe best but the feed ack issue makes me shy to ise it in a bunch of gigs)
Putting borh into the Felix and taking the piezo bark out from the mids. Pretty usable for now.

 

[statsc]

One of the reasons i am interested in the piezo thing right now is I just got a new bridge wirh the Yamahiko for my contrabassetto. I have been having a hard time finding the right pickup ( bridge pickups are too brittle sounding etc)
In rhe past few days i have been finding what sounds best and yesterday i mixed rhe Stat B and Y ( just the E side for both) and got the best sound so far ( the Remic sounds really rhe best but the feed ack issue makes me shy to ise it in a bunch of gigs)
Putting borh into the Felix and taking the piezo bark out from the mids. Pretty usable for now.

What I'm finding when using the ToneDexter is that I can control the midrange by varying the proportion of pickup (FC) and microphone wave map. For quieter situations, 90% mic wave map to 10% pick-up works well; for louder situations, 50/50 works well. The EQ on the ToneDexter and my amp stays flat, except for a bit of bass cut as the volume increases. And of course no feedback or bleed issues!

 

[flatback]

Yeah honestly now that I have the Pickup on the Bass I am saving up for the Dex. I think with all the mics I have laying around (including a great BeezNeez tube mic, the Remic and DPA and a few others) I could come up with some decent wavemaps that would work really well.
What is really encouraging to me is that although my Contrabassetto can be mid forward with a pickup but mic'd well you cant really tell the difference between it and a lot of bigger basses. I hope that that will translate to wavemaps and get an excellent result.
It may vary well end up that the ideal way to make a piezo sound best is with the ToneDexter.

 

[statsc]

Yeah honestly now that I have the Pickup on the Bass I am saving up for the Dex. I think with all the mics I have laying around (including a great BeezNeez tube mic, the Remic and DPA and a few others) I could come up with some decent wavemaps that would work really well.
What is really encouraging to me is that although my Contrabassetto can be mid forward with a pickup but mic'd well you cant really tell the difference between it and a lot of bigger basses. I hope that that will translate to wavemaps and get an excellent result.
It may vary well end up that the ideal way to make a piezo sound best is with the ToneDexter.

I think with the mics you have you could certainly come up with some good wave maps. I made wave maps with 3 different mics: Shure SM57, AMT 25b, and a borrowed $2000 Royer. The AMT and Royer wave maps sound very similar (I actually like the AMT maps a little better). I ditched the SM57 maps.

 

[lowfreqgeek]

I do not see what the obvious reason for a variable input impedance. I do see the obvious reason for a high input impedance. Lowering the input impedance creates a high pass filter. Why can't we let all the bass frequencies through and adjust with a dedicated high pass filter instead of artificially creating a high pass filter with an impedance sweep? Add a good EQ section and a phase switch and you've got all coloring you need combined with your amps tone controls to boot. There's actually already many on the market that have these features

Lowering the impedance does a lot more than just "create a highpass filter". The load impedance of a piezo actually changes the physical properties of the ceramic. It's not just altering the electrical circuit; there is a physical change in the ceramic that alters how the piezo reacts to the compression of the bridge and the vibration of the top. Too high an impedance for a given crystal reduces the electro-mechanical dampening and makes the piezo prone to feedback, even with a variable HPF engaged. It also changes the shape of the amplified note, altering the representation of the acoustic sound.

Since the characteristics of a piezo change depending on pressure, even 2 otherwise identical pickups will behave differently on 2 instruments with different string tensions. Being able to "dial in" the impedance to get similar electro-mechanical response would be ideal.

There's a whole world of piezo sensors out there aside from musical instruments. Load impedance plays a much larger role in optimizing their response and electro-mechanical properties for their intended applications than it does in amplifying musical instruments, but the same principles still apply.

 

[DoubleMIDI]

One of the problems with a piezo is that it can only deliver a very limited amount of current (number of electrons moving through the wire).

With a low impedance (read resistance if you are not familiar what impedance is, it's a frequency dependent resistance and a single value usually is only valid for a certain frequency, which is often 1 KHz), the current needed to keep the voltage is rather high. If the piezo cannot deliver that current, the voltage automatically drops, so that Ohms law is still valid. So the waveform gets distorted when the amplitude of the signal exceeds the ability to deliver enough current for that voltage with the given impedance load.

Also keep in mind that a piezo works both ways, as a sensor delivering electrical output from mechanical input as well as a mechanical actor controlled by electrical input. So there might be some influence back from the electrical side.

And every mechanical object has its own resonance frequencies, often influenced by mechanical pressure from other objects. So that might change the resonance of the vibrating object a lot.
These resonances might be able to get damped to a certain amount by the electrical load (impedance).

It is not an ideal purely electrical filter but one is part of the whole transducer.

 

[flatback]

Yeah thanks for that...so are you saying that having a variable impedance would be helpful? One of the reasons I think the Yamahiko piezo is so good (relative to others) is that the piezo is industrial (It sounds like it is giving you the maximum clear signal possible from a piezo) and it is designed to be inside the vertical shaft of the adjuster (not flat across the wheel of it like a Full Circle) When you plug it in flat, it isnt exactly the most musical sounding pickup but it responds well to even little eq tweaks. The difference between 20M and 10M imp on the Felix for example makes a huge difference in sound. But cutting or boosting also has seemingly quicker and more tonal effect then other piezos I have tried. I would love to know what the ideal imp for it would be.

 

[DoubleMIDI]

I do not have the Yamahiko, only a Full Circle and a Shadow bridge wing crystal piezo beyond my homemade piezo disk pickups for my Clevinger EUB.
I also have a Quick'n'dirty impedance buffer after Francis schematics, but use it only with my Carlsbro Delta 600 if I need the power (very seldom). Otherwise I use my Genz Benz Shuttle 3.0-10T without any preamp.

I ordered some 5 MegOhm pots (seems to be the maximum value for a trim pot, for a regular pot the maximum value seems to be 500KOhms or 1MegOhm) to experiment with in the future.

Together with a second pot and/or fixed resistor there is some useful range to try like 2 to 7 MegOhms or 4 to 9 MegOhms.
But a simple n-way switch for 1, 2, 4, 6, (8,) 10, 15, 22 MegOhms might even be better or in combination with the 5 MegOhm trim pot.

The problem with a pot is that it can oxydize, specially when the current is low. So it would be nice to check out, but not for use over years. A switch or a jumper inside that would keep the setting as long as you keep the pickup in place is less prone to contact problems.

 

[Jefenator]

The best pre I've encountered thus far has been the auxiliary input on my Biesele magnetic pickup. I try to use the fDeck or no pre from time to time and always wind up going back to the Biesele. Some of my favorite aspects of it are:

• Baked-in EQ/HPF: no knobs for all that which might tempt me to be tweaking with settings mid-set or mid-song (I'm neurotic like that - YMMV). It "just sounds good" with my old Realist and Full Circle. (I deduce that HPF is part of the recipe because the signal is boomy as heck, going straight in or via the fDeck with HPF dialed out. May be some other EQ curves in there, not really sure - I just know it works.) There is a phase switch and a pad switch for the piezo input, which both seem very relevant but I can set & forget those and then they're out of the way.
• Mounted On The Bass: no external units I have to plug in each & every time, got a very handy active volume control at the end of my fingerboard (tailpiece mounting would also be dandy - I actually figured out a way to zip tie the fDeck on the back of the tailpiece when I was using that). So for all practical purposes I'm running straight to the amp - 1 cord and done! But it's not just about practicality - I have noticed that it sounds better when I run the pickup straight into an onboard unit than when I run through a 15' instrument cable and have the pre by the amp.
• Power Switch Built In To The Volume Knob: no need to unplug during long breaks to save the battery. Volume is all the way down prior to & after switching so there's no loud thump. AFAIC every battery operated preamp ought to have this feature and AFAIK almost none do.
• Option To Blend In Magnetic Signal: more than any EQ fiddling, I have found the magnetic signal to be a subtle but extremely helpful addition. I usually have just a dash in there for a hint of solidity but if I feel like I'm getting buried, I just crank it up more and I'm back with the pack as it were. The 50/50 blend is like nothing else I've ever experienced. Beyond that as I approach 100% magnetic it sounds more and more like an electric bass, not necessarily in the best way. (But it did save my bacon when my old Realist pickup died.) This will obviously be of no use with gut strings.

Complaints? I sort of wish the piezo input were 1/4" and not 1/8". (But with the right cable or adapter it's not really a problem per se.) Oh, and I guess the fingerboard mounting mechanism can be a tad awkward. (Again, no real thorn in the side once it's set. Do need to check all the thumb screws from time to time...)

My Biesele was hand-built by a guy in Eastern Canada. Looks like he's still at it - at least the site is still up. It's been a labor of love for him - he referred to these as "his babies" when I spoke with him on the phone. But I have to believe there are enough amplified double bassists out there to make it worthwhile for another maker or two to offer their own take of an onboard DB preamp. (Not expecting any mass-production price reductions - AFAIC Beisele's current posted prices are a total no-brainer bargain for the extent to which his product has made my gigging life easier over the last 20 years.)

EDIT: I wouldn't be opposed to variable input impedance. I would probably suggest that it (along with HPF) be adjustable with a trim pot so I could set & forget them and not have two more knobs to turn - accidentally or deliberately - mid-song.

 

[statsc]

This has more/less been my argument regarding piezo pickups for years. Some sound better, though none sound good in comparison to an acoustic instruments tone. For whatever reason a lot of folks are convinced that they are some great "acoustic" pickup, when they are not - just another form of electronic pickup.

The whole Tone Dexter concept intrigues me as well. It would intrigue me a whole more if they had a mid band adjustment and presets though. The argument against having a mid band adjustment on any acoustic preamp is short cited by the builder, no matter how great they think their modeling is. They are kidding themselves if they think that modeling will correct the need to adjust that frequency in a live setting. I twiddle knobs at almost every gig, and I never know which ones I'll need. I hadn't touched my mid knob for months, then at loud gig last weekend - boom needed more mid clarity. Even though I'm a CUT THE MIDS kind of guy, sometimes you need to put some back into the mix.

I would love to see a preamp with an average EQ section, along with some common preset modeling. The Tone Dexter guys pretty well ignored me when I brought it up, but I think it would be awesome to have presets with stuff like: Vintage Kay w/guts, Carved German w/Steels, etc., etc., etc. Like go ahead and pick 6 very common, desirable upright bass tones and have a pro do your modeling training. Like @flatback said, I just want to plug in and find a decent tone quickly - with any preamp.

Some of the EQ sections on the higher end ones scare the ca-rap out of me....so many knobs. Might as well be a graphic EQ. They look like studio tools, not live boxes. I'm sure guys get used to them, but I really like as little as possible to worry about on a gig.

So I guess I'll update my wish list. Here is my piezo only preamp.

1. variable input impedance
2. 3-band EQ with adjustable center frequency for mid band
3. fully accessible switches and knobs top mounted, with no recessed controls
4. 6-10 modeling selections with wet/dry control
5. free standing or mic stand mountable. no stomp box format.
6. hot enough output to drive a power amp easily.

So who's gonna build the Jay Super Deluxe Upright Bass Preamp huh? If you build it, I will try it out free of charge to me! I'm screen shooting this post as proof of concept. The coffee is strong this morning.

Just did some experimenting with the ToneDexter to try to gauge the effect of using a wave map not created by the bass that was playing it. I compared wave maps created using two basses: an old carved Tyrolean flatback and a newish laminated Upton Standard. Both had FC pick-ups; both Spiro strings (Mittels for the Tyrolean; Solos for the Upton); both miked with an AMT 25b in exactly the same positions; both run through an AI Ten2 with the EQ set flat, except for a little bass cut. In every case, the sound was better when using the bass that had created that wave map: fuller, richer, more balanced. The Upton was somewhat better using its own wave maps; the Tyrolean was a whole lot better when using its own wave maps. I suppose that if you had a CCB and used a wave map created by a Prescott it might sound better than one you created yourself with the CCB, but I think in general garbage in = garbage out. YMMV!

 

[Jay Corwin]

Just did some experimenting with the ToneDexter to try to gauge the effect of using a wave map not created by the bass that was playing it. I compared wave maps created using two basses: an old carved Tyrolean flatback and a newish laminated Upton Standard. Both had FC pick-ups; both Spiro strings (Mittels for the Tyrolean; Solos for the Upton); both miked with an AMT 25b in exactly the same positions; both run through an AI Ten2 with the EQ set flat, except for a little bass cut. In every case, the sound was better when using the bass that had created that wave map: fuller, richer, more balanced. The Upton was somewhat better using its own wave maps; the Tyrolean was a whole lot better when using its own wave maps. I suppose that if you had a CCB and used a wave map created by a Prescott it might sound better than one you created yourself with the CCB, but I think in general garbage in = garbage out. YMMV!

Yeah I don't that. It sounds like it's doing exactly what it was designed for. I've said it a bunch of times now that I think it's a great concept, and I appreciate that those guys are pushing the envelope.

But if we are talking about my wishlist - give me a bunch of great presets to try at the flick of switch. I've had good results putting a TC Electronics Bodyrez after my preamp, so it's given me a more positive view of the whole modeling idea.