Conditions for using a Shadow SH-SB2 transducer...

Arduy · #1 06-24-2008, 06:31 AM

Hello to all. When I bought my double bass a few months ago, I also purchased a Shadow SH-SB2 piezo-electric pick up in a hurried manner, without consulting anybody. Maybe it's not really among the best pickups for double bass. I've heard a few negative impressions about it. I'm wondering if anybody uses that pickup and which are the conditions for using it to the best of it's possibilities. Are there any requirements (pre-amp, etc.)? Thank you.

gnasher1993 · #2 05-20-2009, 11:23 AM

I know this thread is really old but I've had the SH SB2 for a while now. It has a really high impedance output so the best amplifier is an amplifier with a low impedance input (2 or 4 ohms is what I usually run at). Also are the discs mounted between the bridge wings or between the bridge and the body? I initially tried the pickup between the bridge wings as this is a much easier installation. I've later found that it really is worth the extra effort to mount the discs on top of the body beneath the bridge. The sound is extremely different and the pickup creates a very warm, natural tone from your bass. Although not the best bass pickup on the market, it's definitely worth the money.

EDIT: I've just noticed that the OP hasn't been active for 5 months now. A moderator can remove this post if you feel it's taking up unnecessary forum space.

bolo · #3 05-20-2009, 11:48 AM

Quote:

Originally Posted by gnasher1993

A moderator can remove this post if you feel it's taking up unnecessary forum space.

Naw don't do that. Most of my contributions here fall into that category.

gnasher1993 · #4 05-20-2009, 12:35 PM

Quote:

Originally Posted by bolo

Naw don't do that. Most of my contributions here fall into that category.

I'm hoping my opinion will be helpful to someone looking for a bass pickup so yeah leave it up if possible.

Nagrom · #5 05-20-2009, 12:48 PM

I have one of these pickups, in the wings, with a fishman preamp. Folks say it sounds good.

**Francois Blais** · #6 05-20-2009, 02:26 PM

Quote:

Originally Posted by gnasher1993

I know this thread is really old but I've had the SH SB2 for a while now. It has a really high impedance output so the best amplifier is an amplifier with a low impedance input (2 or 4 ohms is what I usually run at)

?
2 or 4 ohms is typically a loudspeaker impedance, not intput.

With a high impedance pickup (such as most piezos), it's best to have a very high impedance input, 1 megohms or more.
The best preamps often have a 10 megohms impedance input. (like the Acoustic Image units)

gnasher1993 · #7 05-20-2009, 03:19 PM

Quote:

Originally Posted by Francois Blais

?
2 or 4 ohms is typically a loudspeaker impedance, not intput.

With a high impedance pickup (such as most piezos), it's best to have a very high impedance input, 1 megohms or more.
The best preamps often have a 10 megohms impedance input. (like the Acoustic Image units)

The manufacturer recommends low impedance. Which is what sounds better to my ears with this particular pickup. Perhaps it's different with others, I don't know. I don't mean to cause any confusion either way.

**Francois Blais** · #8 05-20-2009, 06:01 PM

Quote:

Originally Posted by gnasher1993

The manufacturer recommends low impedance.

What does he say exactly?

The pickup doesn't know anything about what's connected at the output of the amp.
Furthermore, there's simply no amp with an INPUT impedance of 2 ohms.
Any signal source would be completely loaded with such an input impedance.
It's almost a short-circuit.

You are probably talking of the output stage, but it makes no sense anyway, since, like I wrote above, the pickup doesn't know anything about what's connected at the output of the amp.

gnasher1993 · #9 05-20-2009, 06:48 PM

The manufacturer says:

Quote:

Shadow Electronics
Piezo pickups and transducers have a very high output impedance. In order to get the optimum sound output we recommend an amplifier with low impedance input.

OK, so I'll admit I got confused with the output impedance thing. But is the manufacturer talking sense? Sorry again for any confusion...I'm also confused now.
Anyway, the pickup sounds great to me so no complaints either way. I would apprecciate some information about piezos and input impedance.

Thanks

Tbeers · #10 05-20-2009, 07:59 PM

FWIW, I don't believe all of the fuss that companies like Acoustic Image make about their "ultra high impedance" inputs. 10 megohm? That's partly marketing BS.

When I first bought my Summit Audio TD-100, which is basically a very nice tube DI with adjustable input impedance, I played my double bass through it (using a Fishman Full Circle) and had a friend turn the impedance knob back and forth slowly. When I told him to stop because it sounded best at that spot, the knob was set somewhat below 1 megohm. (It's not clear exactly where... perhaps 800K or so.)

I definitely agree that a higher than "normal" impedance input benefits the sound with piezo pickups. But don't buy the hype from AI et al. 1 megohm should be perfectly sufficient.

Quote:

Originally Posted by Francois Blais

?
2 or 4 ohms is typically a loudspeaker impedance, not intput.

With a high impedance pickup (such as most piezos), it's best to have a very high impedance input, 1 megohms or more.
The best preamps often have a 10 megohms impedance input. (like the Acoustic Image units)

**Francois Blais** · #11 05-20-2009, 09:46 PM

Quote:

Originally Posted by gnasher1993

Anyway, the pickup sounds great to me so no complaints either way. I would apprecciate some information about piezos and input impedance.
Thanks

Well, Shadow is wrong when they recommend a low impedance input, such as those you'll find on regular bass guitar amp. (10K or 20K maybe)
Plugged into such a low impedance, the pickup will sound very thin and brittle, with no low end.

I agree with Tbeers that 10 megohms is not an absolute requirement. But 1 megohms is the approx magnitude.

gnasher1993 · #12 05-21-2009, 06:53 AM

Thanks, I'm thinking I'll shoot an email in Shadows direction just to make them aware.

bolo · #13 05-21-2009, 02:52 PM

Quote:

Originally Posted by Tbeers

FWIW, I don't believe all of the fuss that companies like Acoustic Image make about their "ultra high impedance" inputs. 10 megohm? That's partly marketing BS.

When I first bought my Summit Audio TD-100, which is basically a very nice tube DI with adjustable input impedance, I played my double bass through it (using a Fishman Full Circle) and had a friend turn the impedance knob back and forth slowly. When I told him to stop because it sounded best at that spot, the knob was set somewhat below 1 megohm. (It's not clear exactly where... perhaps 800K or so.)

I definitely agree that a higher than "normal" impedance input benefits the sound with piezo pickups. But don't buy the hype from AI et al. 1 megohm should be perfectly sufficient.

I understand what you're saying about the Summit sounding best just below 1 megohm. Others here have said same.

In my case, I have compared two pickups (Rev Solo and Planet Wing) with 1 megohm and 10 megohm inputs. To me it seemed the Rev Solo was not very picky, but the Planet sounds noticeably better to me when it "sees" 10 megohms.

Anyway, the point I really wanted to make is that AI doesn't generate any "hype" or "marketing BS" IMO. On their Series I heads, they gave people the option to switch between the two impedance settings with a push of a button. They since settled on 1 megohm inputs some time ago. I don't think it was ever hype. I think it was based on lots of evidence at the time from lots of DB players that older style p/u's like the BP-100 generally sounded much better w/ 10 megohm inputs. IMO, the guys at AI just don't put out hype or BS. Not their style. And I know them personally. Just my two cents of course.