Do we really need piezo-optimized DI?

Piezo pickups are extremely sensitive to impedance. A piezo optimized pre or DI is a must.

Radial, Sansamp... I had a Boss Acoustic Pre years ago that was tremendous sounding.

There's a lot of good stuff out there.

 

As for the desirability of optimization, yes, the input impedance should be optimized. See here for more details.

Chris-- As I'm sure you know well, the tone-shaping ("eq") that you do for your on-stage sound may be very different than what you likely would want for the FOH. Were you saying that you adjust on-stage for the FOH sound? Of course, no matter what you do, the sound-guy will have his own tone-shaping, so I wasn't sure what you meant. As for not allowing anything between your bass and the amp, I absolutely agree. Letting anyone do that is a recipe for disaster.

 

Bring your own DI and you know what happens.

If you don't use an impedance buffer (like the HPFpre) at all for your amp or want to go dircectly FOH without an amp, you need an active DI box with a high impedance input. 1 MegOhms is minimum, but if you want to use your amp too, you better have no less than 5 MegOhms input impedance on the DI box, because DI impedance and amp impedance are in parallel, so the effective impedance is lower than any of both impedances alone, with the worst case half the lowest impedance if they are almost the same. So a minimal load (i.e. 5 MegOhms) won't change much for a 1 MegOhms amp impedance.

If you put a DI box (active, maybe also passive) behind a impedance buffer or preamp, the input impedance of the DI could be as low as about 10 KOhms, but never put such a box immediately after a passive piezo output.

I got a cheap DI box myself, that I rather seldomly use. It has a 1 MegOhms impedance (a bit low), but uses a JFET opamp inside which can operate with a higher input impedance, so it is only identifying the 1 MegOhms resistor and replacing it with a 1/4 watts 4,7 MegOhms or 10 MegOhms resistor. My one is a cheap china clone of a BSS-133. Not top quality, but OK for the few times I may need it. Paid about 30 to 40 Euro at Thomann in Germany for it, I think. At least good enough for some experimenting before thinking about getting a better more expensive one.

 

Depending on your setup and amp, it may not be an absolute necessity to have one. The Countryman Model 85 DI is a stapel for sound engineers that do live concerts. It has a switch with a "pickup" setting that sets the input impedance at 10 megohms. Most newer amplifiers already have a 1, 2, or 4 megohm input impedance and an XLR Direct Out on the face of the amp. With either of those setups you wouldn't need your own DI. Just as Chris mentions above I never put the DI in between the pickup and the amp, because it can alter the tonal characteristics of the pickup.

If you wanted to get one , the Stagebug is a cost effective way to go. The best sound I've ever experienced was a Realist into a Avalon U5, but that's a very expensive box and it's rather bulky. Marc Johnson uses this setup.

Which in many cases will have you running into the Country Man.

+1 With most pickups the timbre of the pickup will be altered if you run the DI between the pickup and the amp.


Ric

 

I opted for a Fishman Platinum Pro for use with my Fishman Full Circle on my Double Bass. It works well, you have to watch the input gain for clipping IME, but it did make a great difference when I added it instead of plugging directly into the amp. It also has pre and post EQ DI outs and a ground lift, so live and studio engineers find it easy to work with.
http://www.fishman.com/product/pro-eq-platinum-bass-preampeqdi

 

Roy,
For your setup with the Full Circle, the Pro Platinum EQ is the ideal buffer pre amp for that particular pickup. Since it has a built in DI you're going to get a great sound into your amplifier and through the DI to the house. Whether that would work as well with the original Realist is hard to say. They are, after all two very different animals. The Full Circle jack also has a passive filter built into it that the Realist does not.

Ric

 

I have heard people get good results with the Fishman Bass Blender and the Realist as well as the Radial DIs. You definitely have to try the combinations.
On a totally unrelated note, I was doing a large orchestra date a couple of weeks ago and the backline rental SWR went down. Carvin bass into Countryman DI and through my wedge=problem solved!
The Countryman DI is definitely an Industry Standard and goof proof. As you said, there are a lot of good choices.

 

Roy,
I actually owned the original Fishman Bass Blender, it's interesting that you remembered that combination. I didn't have the Realist when I was using the box, but it worked quite well with both the BP-100 or the Underwood.
In combination with that little Crown GLM 200 Condenser Mic you could really warm up the sound coming of either those two pickups. The Pro Platinum was likely the of shoot of that earlier device.

RIc

 

The Baggs Paracoustic DI/pre amp has an impedance of 10 meg ohms:

http://www.fine-fretted-friends.com/baggs-para-acoustic-di

That's more than the Stagebug or the Radial DI Box and 10 Megs will handle any piezo pickup on the market.
I have been using one with my Bass Max ...and now the Schatten RB1.... for 14 years. It's very clean and transparent, unlike the Pro Platinum.
If you don't want any controls on your DI then the Stagebug should do the job nicely.
Personally....I would never use ANY piezo pickup without a pre-amp.

 

Depends which Radial you're talking about. My Radial PZed-Pre is 10 meg Ohms.

Not a complete list of Radial schtuff, but a few more potentially suitable Radials, for reference – in descending Ohmer:

Radial PZ-DI: 10 meg Ohms (a stripped down PZed-Pre?)
Radial StageBug SB-4: 5 meg Ohms (optomised for Piezo, according to Radial)
Radial Firefly: 3.9 meg Ohms
Radial StageBug SB-1: 800 k Ohms

PZed-Pre
Very versatile little box. With the Piezo buffer off, the input drops from 10 meg Ohm to 6.8 k Ohm. Output is 1 k Ohm. Two DI outputs, one pre-EQ & one post-EQ w/ ground lift; a tuner out, HPF, EQ etc. It is the core of my amped sound.

But my Pre is my DI.

I would've thought that getting the sound that's closest to the source out to FOH would be the way to go. I thought the Radial's various outputs are buffered and independent, so I've never tried anything other than the following (whether using my own amp or a house amp; I'll avoid amps altogether when possible and just use the Pre) Here's my rig with the signal split by the Radial:

Bass/Underwood > Radial Pre 1/4" > EA Micro/Wizzy 10
ˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇ\ DI XLR > FOH

Should I be using the EA's DI?