Need help not wasting money - need amp for upright with piezo

[Billgore]

I'm trying to get my upright bass ready to play out. It has a piezo pickup installed and I have an Avenson Audio Small DI also attached to the tailpiece.

The Avenson D.I. is GREAT for going direct - it uses phantom power and a JFET. It has 10Mega-ohm input impedance and XLR out, with unity gain. I can't tell you how great this D.I. is at going direct. But I don't use it for recording because my USB interface also seems to have ultra-high input impedance (it sounds great too, a volt 476.)

Now, I want to invest in an amp for practice and for playing out. I love the idea of plugging into a 200w or 300w combo amp with a 15" speaker because of the simplicity of it. I'm thinking keep it classic - drape an SM58 or whatever over the front of a loud combo amp and call it done.

obvious problem - I start amp shopping and looking at the Fender Rumble series, the Ampeg RocketBass series, the Ashdown Studio series (never heard of that one before) ---- well that's as far as I made it before I concluded that they are all going to have 1 Mega Ohm input resistance. After hearing the difference that the 10 Megaohm Avenson DI made going direct, I'm simply not willing to get back down to 1. Too much noise, no fat full bass tone.... so sad. I could build one of these???? http://www.scotthelmke.com/Mint-box-buffer.html
its a little buffer in a mint tin. But he doesn't actually mention what the input impedance IS...


Here's option B ---- I have some outboard stuff stuffed in a closet. I have an older Art Pro Channel channel strip in there. So, I COULD use the Avenson D.I. into the channel strip, maybe I'd get some benefit out of the compressor? ... EQ it down into bass land, and then BUY, instead of a bass amp, a powered full range speaker cabinet. They always seem to have a couple collecting dust at the pawn shop.

Less simple. Less cool. Might sound better, might sound worse. Too expensive to try BOTH options at once for an A/B comparison.... and I live out in the hills... so I'd REALLY appreciate some opinions, wisdoms, reality checks, or relates...

Thanks all.

TLDR: Have upright bass with piezo. Piezo wants 10 Megaohm input. I want a bass amp but all I have is a channel strip and a D.I. (Don't own any form of speaker cabinet for the bass yet)

 

[seamonkey]

I've been using an ADI21 for DB with a piezo bridge pickup for years. 5Mohm input impedance, XLR DI for FOH

Behringer ADI21 V-Tone Acoustic Driver DI Pedal

There's a Double Bass forum here that will have much different opinions.

 

[ahadl2500]

Have not used one, but PJB combos are popular with double bass players. They list high input impedance and compatibility with piezo setups in their owners manuals. For the output you want the BG400 is probably the one to get.

P: BG-400 Suitcase Compact | Phil Jones Bass

I have used PJB cabinets (own 2 Compact 8s and 3 Compact 2s) and I am a fan.

 

[beans-on-toast]

Acoustic Image

 

[agedhorse]

Most piezo pickups work best around 1M, only a very few (small crystal format) require higher input impedance. The load helps define the damping of the crystal, too high and the crystal will become harder to tame. Another benefit is the reduction of the tribo-electric effect (electro-mechanical interaction causing the capacitance of most cable to vary with movement causing noise) and also circuit noise.

The push for very high input impedances started out with some good science, but as pick-ups evolved, they became much more robust and could benefit from 1M loading. It really depends on the crystal structure, but if you look at the Rosette (a fairly high end acoustic amp), 1Meg was what most players chose as the "best" during the development of the amp. This agrees with the previous 7 or 8 acoustic amps I designed over the years.

 

[Billgore]

Thanks for weighing in everyone. Sounds like I need to get my bass over to a music store where I can try some stuff out.

Agedhorse, now that you mention it, I said "going back" to 1 meg, but that was actually a lie i invented at some point. The other d.i. boxes I had tried where probably much lower than that in reality....

So maybe

There is no problem

At all

Happy new year lol

 

[Billgore]

That being said, my bass is pretty old and came equipped with a piezo that I know nothing about. So we'll see.

 

[basss]

I've used combos from the Fender Rumble, Ampeg RB and Ashdown Studio series and they all sound decent with upright but a preamp will help a lot. I recommend the Red Eye preamp. Easy to use and really helps piezos work with amps and PAs. Red Eye Preamp There's a whole forum dedicated to upright bass amplification on the DB side of talkbass with lot's of info/options.

 

[daveman50]

You can also look at the double bass forum's amp section to see what them there fellas like

 

[Pop C]

Most piezo pickups work best around 1M, only a very few (small crystal format) require higher input impedance. The load helps define the damping of the crystal, too high and the crystal will become harder to tame. Another benefit is the reduction of the tribo-electric effect (electro-mechanical interaction causing the capacitance of most cable to vary with movement causing noise) and also circuit noise.

The push for very high input impedances started out with some good science, but as pick-ups evolved, they became much more robust and could benefit from 1M loading. It really depends on the crystal structure, but if you look at the Rosette (a fairly high end acoustic amp), 1Meg was what most players chose as the "best" during the development of the amp. This agrees with the previous 7 or 8 acoustic amps I designed over the years.

I have a 2013 Walkabout Scout, with the 15 inch woofer. I don't know if this was one of your designs, but I do know it sounds absolutely great with a double bass. Also, the DI is fantastic! Hats off to whomever designed this combo!

 

[Paul New]

I have an Acoustic Image combo and a GK 2/10 combo. GK’s amps feature 1 MegOhm input impedance.

 

[Dave Hill]

GK MB112-II.

 

[climber]

I no longer play upright, but I did for a long time. I would get a cabinet with a 12” speaker. A 15 will be too muddy IMO. Also get a stand to lift the amp off the floor so u can hear it better. Your intonation will thank you. Look at any Ron Carter video from the past 10 years at least.

 

[Lesfunk]

Acoustic image seems to be popular among the upright players that I know

 

[agedhorse]

I have a 2013 Walkabout Scout, with the 15 inch woofer. I don't know if this was one of your designs, but I do know it sounds absolutely great with a double bass. Also, the DI is fantastic! Hats off to whomever designed this combo!

Not my design, but it has a 1Meg input impedance.

 

[agedhorse]

Thanks for weighing in everyone. Sounds like I need to get my bass over to a music store where I can try some stuff out.

Agedhorse, now that you mention it, I said "going back" to 1 meg, but that was actually a lie i invented at some point. The other d.i. boxes I had tried where probably much lower than that in reality....

So maybe

There is no problem

At all

Happy new year lol

Most passive DI’s are between 50k and 100k, too low for an unbuffered piezo. Most active DI’s (with the pad off) are 1Meg.

 

[Billgore]

I've used combos from the Fender Rumble, Ampeg RB and Ashdown Studio series and they all sound decent with upright but a preamp will help a lot. I recommend the Red Eye preamp. Easy to use and really helps piezos work with amps and PAs. Red Eye Preamp There's a whole forum dedicated to upright bass amplification on the DB side of talkbass with lot's of info/options.

Help with what exactly? I tried a k&k pure and it seemed like I didn't need the extra gain, compared to any other magnetic or piezo pickup, seemed the only problem was the impedance which was not corrected by the k&k. Boy was it noisy and horrible distortion to boot. During my a/b comparison into my DAW, the preamp was the worst with every configuration. I figured it was just redundant and yet I wouldn't think you'd go straight into a power amplifier from a little preamp like that.
...?

 

[GreyBeard]

I heard a guy in rockabilly group not long ago playing upright through a Fender Rumble 100. Sounded great.

 

[g-dude]

I use the Mesa Rosette 1x10 with a clip on mic. You can also easily use it with a pickup.

Bass sounds good, and there are enough controls to help you deal with most issues you might run into.

I was somehow able to dial in enough volume to hear myself on a stage with:

- Two trumpets
- Saxophone
- Flute
- Electric guitar going through a wedge on my right
- Electronic drums cranked up on my left
- Keys
- Accessory percussion
- Acoustic guitar
- Five singers who seem to think that their monitor levels should cause hearing damage

I won’t even count the violin, viola, and cello because they were clear on the other side of the stage from me.

The DI out also proved handy, as did the tilt feature.


I also used it with the jazz quartet I put together to recently play at an event at church. Easily enough volume to sound good as the only sound reinforcement in a large gym.

Amp isn’t very heavy at all. It’s a keeper.

 

[jmlee]

The 1 Mohm or greater input impedance doesn't have to be in the amp per se. My Full Circle pickup runs initially into one of Fdeck's HPFs which have a nominal 10 Mohm input impedance, and from there the signal runs into whatever I want to use for amplification—or sometimes just what's on hand somewhere. Being kind of lazy I usually stuff the HPF into my bow quiver for jazz gigs and that gives me, right where I am, volume control plus HPF cut-off frequency and the option to invert the signal to reduce feedback ringing.