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funkyjazzjunky
Advanced Member
Username: funkyjazzjunky

Post Number: 282
Registered: 5-2007
Posted on Tuesday, November 25, 2008 - 1:08 pm:   Edit Post

Do any of you use the SuperFilter with a double-bass?
llobsterbass
Junior
Username: llobsterbass

Post Number: 39
Registered: 5-2004
Posted on Wednesday, November 26, 2008 - 12:47 pm:   Edit Post

Interesting idea. Might be an innovative way to cut onstage feedback...or it could blow up your doghouse if you set it wrong!
richbass939
Senior Member
Username: richbass939

Post Number: 1006
Registered: 11-2004
Posted on Wednesday, November 26, 2008 - 6:59 pm:   Edit Post

Yes. After I got my SF I finally was able to get a sound I liked with my upright. I like its acoustic tone but I was always fighting with it to get a good amplified tone. The SF gives such good control I can just dial it in. It took some playing around with at first but I'm really happy with the results.
Rich
funkyjazzjunky
Advanced Member
Username: funkyjazzjunky

Post Number: 283
Registered: 5-2007
Posted on Friday, November 28, 2008 - 9:09 am:   Edit Post

Rich,

I play a double bass, is your upright and bass viol or an EUB?

I want to get a 'true' amplified sound without losing the 'blossom' of a bass note.
richbass939
Senior Member
Username: richbass939

Post Number: 1008
Registered: 11-2004
Posted on Friday, November 28, 2008 - 10:08 am:   Edit Post

Vann-Di,
Mine is a 3/4 German bass violin, circa 1910.
I have an L.R. Baggs Ultra Bass pickup on it. It is the only pickup I have ever had on it so I can't do any kind of comparison. I installed it exactly as I understood the directions so I guess it is in the right place.
Unlike its rich, dark acoustic tone, it sounded pretty trebly through the Baggs. Before I got the SF I had to EQ the amp all the way bassy (no preamp). With the SF I love the control I now have.
When I play a gig with only the upright I set the SF at:
Filter A: low pass
Freq Gain - 9
Freq - the line just counterclockwise from 110
Damp - 7

Filter B: low pass
Direct Gain - 0
Freq Gain - 6.5
Freq - There are 2 lines between 45 and 110. I set it on the line closer to 45.
Damp - 10
I set the amp EQs flat.

When I play a gig with both the upright and an electric, I use one filter per bass and set the upright like Filter A above.

I leave everything the same for arco and pizz except for the volume (I turn down a bit for arco).

The only thing that is more of a challenge with the SF is feedback. With the Baggs straight into an amp I had virtually no feedback problems at low or moderate volumes, even with the amp straight at me. With the SF, amp placement is more important. The dramatic improvement in tone is worth the extra trouble, though.
I'm sure there are a lot of good tones I could get with the SF. I'm not really one to constantly tweak the settings. I might adjust things a little for the room but basically I leave the settings alone.
Good luck to you in finding some tones that you like.
Rich
funkyjazzjunky
Advanced Member
Username: funkyjazzjunky

Post Number: 285
Registered: 5-2007
Posted on Friday, November 28, 2008 - 12:34 pm:   Edit Post

Thank you so much. Once I get it and set it up I will update the post.
orbit
New
Username: orbit

Post Number: 1
Registered: 12-2008
Posted on Saturday, December 27, 2008 - 11:44 am:   Edit Post

Rich,

I just purchased an upright bass (its kind of a custom thing, its normal scale length, full or 3/4 im not precisely sure, but it is only 12 inches wide so that it can easily be transported) and it has an LRBaggs ultrabass pickup as well.

it seems like there is an awful lot of hum to get things to be loud enough. is this normal or could it be that the pickup is defective?

thanks for any info you can send my way.
richbass939
Senior Member
Username: richbass939

Post Number: 1020
Registered: 11-2004
Posted on Saturday, December 27, 2008 - 4:23 pm:   Edit Post

Jakob, I don't think I will be much help to you because I don't know very much about them (or gear in general, for that matter).
I just installed my pickup per the instructions and plugged it in. It never did hum so I didn't have to troubleshoot anything. If anything looks loose, that would be a start. Does the cable (or amp) you are using hum with anything else? If you can, try other cables and amps and see if it still hums. I have owned older amps that have a polarity switch that can cancel a hum.
If you go to "Owning an Alembic" and "Troubleshooting" section on this club and start a new thread about your problem, it will probably be solved pretty quickly. I'm always amazed by how much knowledge the club membership has.
Good luck with the hum problem. I know how annoying it can be.
Rich
orbit
New
Username: orbit

Post Number: 2
Registered: 12-2008
Posted on Saturday, December 27, 2008 - 6:28 pm:   Edit Post

Rich,

thanks. I am suspecting the possibility that my house has grounding issues or electrical interference because i seem not to recall the same hum issue when i bought it from the previous owner, but then i dont think i really played it real real loud either.

what i am scared of, is that since this bass is only 12 inches wide (not deep, wide), it might be that the pickup needs more gain than a normal upright does and thus i will get more noise but at the same time, the levels i had set on my bass amp, if i were to plug in my carl thompson i would not have anywhere close to the amount of hum present when i plug in the upright.

(Message edited by orbit on December 27, 2008)
richbass939
Senior Member
Username: richbass939

Post Number: 1021
Registered: 11-2004
Posted on Saturday, December 27, 2008 - 9:35 pm:   Edit Post

You could check your house electricity with a tester or by an electrician.
What type of upright is it that is only 12 inches wide? Do you have a picture you could post?
Rich
dfung60
Advanced Member
Username: dfung60

Post Number: 370
Registered: 5-2002
Posted on Saturday, December 27, 2008 - 9:57 pm:   Edit Post

Orbit -

Piezo pickups like the Baggs in your bass aren't sensitive to the kinds of hum sources like regular magnetic pickups, so it's very unlikely that the hum problems are due to your house electricity or the other kinds of things that emit hum (light dimmers, large motors, etc.).

If you plug in another instrument and don't have any unusual hum issues, then there's probably a wiring problem in your upright bass. If you haven't already changed the battery, that would be the first thing that you want to do. After that, you need to check all the connections to make sure that everything is solid. Beyond that, it would have to be a problem in the pickup or in the preamp/electronics module and would probably be difficult to diagnose with only that instrument (in these cases, you identify the problem by swapping parts with a known good set to isolate the faulty component).

Hopefully it will just be a dead battery or bad power connection. When the power supply is insufficient, you'll get a lower output level, which requires you to turn the gain up; when you increase the gain level of your amp, you'll increase the loudness of background hum as well.

Hope this helps,

David Fung
edwin
Advanced Member
Username: edwin

Post Number: 377
Registered: 5-2002
Posted on Sunday, December 28, 2008 - 10:05 am:   Edit Post

Rich, one of the problems you might be using the SF to get over is that of impedance matching. A piezo pickup likes to see a preamp input impedance of over 1megohm (1 million ohms) while most standard amp and preamp input impedances are much lower than that. It's good you can get past it with the SF, but you might try using a proper piezo buffer before any other electronics and find that the low end returns.

Orbit, it sounds like you have a grounding issue with your bass. Hum is something that magnetic pickups pickup, as David pointed out, so the first thing I would check is the ground continuity starting at the input jack. It should be pretty easy to find.

Edwin
richbass939
Senior Member
Username: richbass939

Post Number: 1023
Registered: 11-2004
Posted on Sunday, December 28, 2008 - 9:45 pm:   Edit Post

Edwin, thanks for the tip. I don't know anything about buffers. Is there one you can recommend?
Rich
orbit
New
Username: orbit

Post Number: 3
Registered: 12-2008
Posted on Monday, December 29, 2008 - 1:25 am:   Edit Post

thanks for the tips guys...

as far as the pickup goes, the bass itself has only ever, after being constructed, sat in the creators house and hasnt seen more than a few hours use. the pickup itself only has 1 thin wire going from the jack to the piezo piece that is glued to the underside of the bridge...theres nothing visibly wrong, so im hard pressed to see how i can actually check the ground continuity???

if you guys think pics will help ill track down a camera...and rich i might do so for your curiosity anyways....it happens that the guy that made it is my parents' doctor, and hes friends with tom rutley (santana bassist for some years) and so he had rutley QA it so to speak....

EDIT: There is no battery used on the baggs ultra-bass pickup

(Message edited by orbit on December 29, 2008)
orbit
New
Username: orbit

Post Number: 4
Registered: 12-2008
Posted on Monday, December 29, 2008 - 11:08 am:   Edit Post

here are some pics for rich and also (not the best, but something at least) pics showing the pickup and how its only one thin wire...

http://i27.photobucket.com/albums/c173/jprumers/newbass.jpg

http://i27.photobucket.com/albums/c173/jprumers/ole0.jpg
richbass939
Senior Member
Username: richbass939

Post Number: 1025
Registered: 11-2004
Posted on Monday, December 29, 2008 - 11:18 am:   Edit Post

That's a pretty interesting design. It definitely would be easier to transport. I see the soundhole under the tailpiece. Are those small soundholes that I see near the upper "bee stings"?
Rich
dfung60
Advanced Member
Username: dfung60

Post Number: 372
Registered: 5-2002
Posted on Monday, December 29, 2008 - 9:43 pm:   Edit Post

Orbit -

OK, between the description and picture, I see that the Baggs pickup is a passive piezo pickup. It doesn't pick up up hum, but you really do need the buffer amp that Edwin mentions to get good sound from most amps. Without it, the output from the instrument will seriously lack bass.

Impedance is sort of the AC equivalent of DC resistance. Resistance is simple to calculate and characterize; impedance is really complicated, as it varies with frequency and amplitude. From a setup standpoint, if you want to deliver a full-range signal to your amplifier, the input impedance of the amp must be much higher than the output impedance of the pickup. For magnetic pickups, amp input impedance of 40-100K ohms will work great.

The output impedance of a piezo pickup is much higher than a magnetic and requires an input impedance of something like a megohm or more to get a flat response signal. It's no problem to build a solid state/op-amp preamp to provide the proper loading. A preamp which has very high input impedance and doesn't boost the signal level (unity gain) is called a buffer amp. It's a necessary part of the signal chain, but people don't want to cut up acoustic instruments, so the buffer is often outboard.

The thin single wire is actually a coaxial cable - the signal passes through a center wire which is surrounded by insulation and the other conductor which acts as a shield.

If the output jack is not a factory-made connection, this is probably where the ground problem is - it's hard to make coax connections cleanly, so I'd definitely check the output jack connections. You probably will need grounded shielding around the area where the output jack is located. If you don't have that, the tiny unshielded stretch of the coax center conductor can be the source of the hum.

If you have a 1/4" jack mounted on the instrument and room for a battery, then there are many internal buffer amps that you can use including systems from Baggs or EMG. There are also a lot of external system including Fishman, Countryman and others over a wide range of prices.

David Fung
orbit
New
Username: orbit

Post Number: 5
Registered: 12-2008
Posted on Tuesday, December 30, 2008 - 12:22 am:   Edit Post

sigh...this is pretty well over my head david...i dont know how i would check the output jack connection? the output jack has the baggs logo and ultrabass logo on it so its not a custom jack its a factory made jack.

ive no idea how to tell if its ground shielded. the creator of the bass bought the pickup and installed it to specifications.

Rich, yeah there are small soundholes and they are designed to look like eyes in conjuction to the soundhole "mouth" its pretty clever IMO...the "bee stings" are actually free floating or whatever so there is free-er vibration...thats what the creator was telling me.

its surprisingly loud for such low body mass compared to a normal standup...and yeah its SO nice transporting it, i drive a mitsu mirage TWO DOOR and i just recline the front seat and put it on its side and it fits perfect, a HUUUUGE perk for me, i could not own a normal upright for this purpose....

now if i can only get this thing sounding good through my amp!

David...i think i would be better off taking the bass to my local hoffman music store and seeing if they will let me put another pickup on it (one that isnt permanently/semi permanently attached like mine) and seeing if another pickup sounds much better and then if it does i will just replace the whole pickup and get one of those buffer amps.

does that sound like a good plan of attack?
orbit
New
Username: orbit

Post Number: 6
Registered: 12-2008
Posted on Wednesday, December 31, 2008 - 12:09 pm:   Edit Post

also david, can you help me find a buffer amp? this seems to be a very specific type of gear and i cant find anything that seems specific to using it with an upright or anything?
dfung60
Advanced Member
Username: dfung60

Post Number: 373
Registered: 5-2002
Posted on Thursday, January 01, 2009 - 12:58 am:   Edit Post

Orbit -

Thanks for the good description. I wasn't familiar with the Baggs pickup which is why I keep making mistakes about its specifics (it's passive, etc.). Each followup prompts me to do a little more research...

First off, you don't need to try to debug the output jack connection. When I looked up a picture of the Ultrabass pickup, I realize what that round thing in your picture was. The coax cable from the pickup element is going into the Ultrabass jack assembly and this was assembled at the factory.

The white wire you see is a coax cable. There's a thin conductor running down the center of the wire which carries the signal from your instrument. It's surrounded by insulation and that's wrapped with a foil or braided metal shield, then there's another insulating cover around the shield which is the external appearance of the wire. To avoid hum, that center conductor must be surrounded by a grounded shield over it's entire length to the output jack and continued over your guitar cable to the amp. The shield blocks electromagnetic fields in the air - if there's any gap, the EM field will leak into the signal and cause hum.

So, this whole grounding discussion had to so with whether the full length of the cable was shielded, particularly where it connects to the output jack. It's easy to make a mistake there when you're wiring up a regular output jack like a Strat or Les Paul. In your case, Baggs built the output jack area inside a metal housing, so you don't have to do anything special.

The bad news is that it's starting to look like there's a damaged conductor or shield in the pickup assembly or ourput jack and that may be hard to fix.

The best test for this kind of problem is to substitute a known-good pickup for the questionable one and see if the problem goes away, which is what you suggested at the end of your post. If they have a unit out, you can just hold it against the bridge and see if there are buzz or output level problem. That's cheaper and faster than any test you can do on the Baggs.

I've never used an external buffer, but what you're looking for is an external preamp that has at least 1 megohm input impedance and hopefully 10 megohm. On the low end, you can get a Fishman BII (around $50). There's probably no limit to how much you could spend on a buffer, but devices like the D-TAR Solstice (this has two channels and EQ) would be around $325. Baggs has a product called the MixPro which would also work (this one looks like it's $160).

If you're changing pickups, then you might look for a system that includes a pickup plus external buffer amp.

David Fung
edwin
Advanced Member
Username: edwin

Post Number: 378
Registered: 5-2002
Posted on Thursday, January 01, 2009 - 1:51 am:   Edit Post

I'd like to second the D-TAR Solstice. I've played with a ton of acoustic musicians who have used everything out there and this is the most musical sounding preamp of its type I've heard. It's also incredibly versatile and has every patching and routing option you could want. I had one for a while and sold it to our guitarist, Vince Herman, but sadly it grew legs after a gig in Charlotte. He keeps talking about getting another and we're all waiting as it gave him the best sound for his acoustic and mandolin that we've heard. It's got patch points for a more sophisticated EQ should you need it.

Edwin
orbit
New
Username: orbit

Post Number: 7
Registered: 12-2008
Posted on Thursday, January 01, 2009 - 1:06 pm:   Edit Post

edwin...that looks like a nice preamp, but 24db of gain on the 1/4 in, that sounds like it is not going to be NEARLY enough for my bass? or is the fact that its a 10megohm input going to fix my problem?

it almost seems like the hum issue i have is simply because i have to give so much gain to have a loud enough output...and by so much gain im talking about 85-100 db of gain :P

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