Official Luthiers Forum!

This isn't an advertisement, just a link to D-Tar Mamma Bear being Demoed by John Jorgenson. You'll love his glasses and hair!

There are a number of ways to access whether you are cable modem, high speed, or dialing up. Enjoy.

http://www.d-tar.com/mama_bear_videos.shtml

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http://www.dickeyguitars.com

Thanks, Bruce.   

Mama Bear started as a concept in 1989 when I was still working for Gibson running the West Coast R&D lab.   My chief engineer, Cliff Elion, demonstrated to me what was probably the first amp modeling...a Marshall turned up to 11 created as an algorithm in an IBM PC.   I immediately asked if it could be done with acoustic guitars, and he said yes.   Gibson management shut down our modeling experiments...no future...but I went on to design the basic functional architecture for an acoustic modeler.   Mama Bear is amazingly similar to what I outlined in about 1994 in a proposal to Chris Martin.   I made the mistake of telling Chris that such a device would be capable of making an Ovation sound like a D-28...   He didn't go for it...then...and now he's got the Aura project.

In 2001 I was invited to participate in a "future of acoustic amplification" focus group at NAMM hosted by Seymour Duncan's Evan Skopp.   While most talked pickups, I came in with the idea of acoustic modeling.   Evan liked what I had to say and invited me to meet with the other SD folks in Santa Barbara. I did, and they invited me to partner with them on the Mama Bear project and the new company now known as D-TAR.   Cathy Carter Duncan and Seymour Duncan put up most of the dough for R&D on Mama Bear, and we showed the first prototype at Healdsburg in 2003.   

I was somewhat astonished that a piezo pickup could sound that full and natural. Nice product...

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"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

[QUOTE=Rick Turner] I made the mistake of telling Chris that such a device would be capable of making an Ovation sound like a D-28...     [/QUOTE]

Oops...

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Dave Rector
Rector Guitars

Remarkable product! Hat's off to thinking outside the box! Bravo, Rick!!!

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JJ
Napa, CA
http://www.DonohueGuitars.com

Any kind of pickup is a simplification of what the real acoustic output of a guitar is.   So the deal was to identify what was missing as well as what a piezo added that we don't want.   So there are basically two sets of algorithms, one set that can neutralize gross pickup artifacts and do some pre-eq, and then another set that can overlay the sonic signature of wood and air onto the neutralized signal.

One thing I picked up from Jorgenson was the phase thing. By pushing the switch it reverses whatever it's on, sometimes helping with limiting feedback.

This contraption while visible in Acoustic Guitar Magazine and Guitar Shows, has never been witnessed by most of the guitar world, I'd hazard a guess. Just appeared to be worthy of applauding the obvious efforts made to pump up a player's arsenal and ability to contour sound production. Impressive.

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http://www.dickeyguitars.com

I'll tell you, I learned a lot about guitars doing the recording sessions where we analyzed the tonal signature of the instruments used for the models.   I had five pre-war Martin dreads including a couple of '34 'bones with bar frets, several OMs, two Loar L-5s, three great J-200s from the fifties on up to fairly new, early Nationals, a great DuPont Sel/Mac style, a pre war...Civil War that is Martin, some great J-45s, L-00s...etc; then a Traugott, a Claxton, and a McAlister; a Ramirez 1a, a couple of Howe Ormes, one of my own guitars (Ms. Antarctica).   I probably recorded forty fantastic guitars, mostly vintage stuff, and we pared that down to sixteen.   It was really interesting recording guitars under such controlled circumstances and hearing and literally seeing some of the differences, particularly in polar patterns (forward projection vs. enveloping sound) and apparent loudness of the different instruments. My current building of real guitars has been very much informed by the experience of helping to design virtual acoustic guitars, especially with this stiff back vs. floppy back thing.

In general I am almost always unhappy with the sound of acoustic guitars that have been amplified poorly.  Even with a good pickup the sound is not very acoustic.  I have tried just about every pickup/mic setup around but get frustrated with the unnatural sound that most put out.

I had heard of acoustic modeling setups but had not heard the D-Tar and had dismissed most other setups as close but no cigar at best and just gimicky at worst.  But the Mama Bear!!!... oh my... I have tried modeling amps and modeling electronic setups of various types but I have never heard one that make an amplified acoustic guitar sound like a great acoustic guitar until now.

I was so impressed with the videos of John and the sound of the Mama Bear that I immediately went out and bought a Mama Bear...today!!!

Rick

Do you have any plans for something similar for bass players?

Al

Mama could be programmed for bass sounds.   The chip on which all the algorithms are stored is a plug-in.   At this point it's a matter of our trying to catch our financial breaths...the R&D on Mama was way North of a quarter of a million bucks, and so we've got a long way to go before we can really afford to do much else right now.   

Ultimately I'd like to have a full range of instruments' signature sounds programmed...mandolins, ukes, banjos, trombones, pianos, etc.   Ever wonder what your guitar would sound like if it had the resonances of a 9 foot Steinway or a baritone sax?   It's all doable...

Think of this as being like 3 D EQ...we're able to manipulate the time/phase relationships in addition to frequency info, and that is the real key to understanding what makes one instrument sound different from another. Much of it is in those all important phase relationships.

I still want to be able to try some different recording methods. I'd love to do the more distant mic techniques favored by my pal Kavi Alexander, but you have to either do it in an anechoic chamber or in a large space where the reflections come pretty late.   Out doors in a really quiet environment would work for that, too.   But the thing is that the real sound of a guitar only starts to coalesce about four to five feet away where all the in and out of phase top and air motion integrates.

Very impressive Rick!

I started using amp modeling on my Twin a few years ago and I was more impressed by the results than any other box that I had ever used.  I think that modeling is definitely the future and we are fortunate that you have brought it to the acoustic guitar today!

We've barely scratched the surface on this stuff, as big a breakthrough as I feel it's been.

One of the things we learned is that there's nothing like the pluck of a string to excite the top in a way that is useful.   Knuckles, hammers, piezo activators, exploding wires inside the guitar body, snapping magnet wire looped around the strings...we tried it all, and there's nothing quite like the way a real player plays the strings to make a guitar sound like it should... Thank you, Laurence!

[QUOTE=Rick Turner] My current building of real guitars has been very
much informed by the experience of helping to design virtual acoustic
guitars, especially with this stiff back vs. floppy back thing.[/QUOTE]

Rick, is there any chance you could say more about that?

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Mike

"The Dude abides. I don't know about you but I take comfort in that. It's good knowin' he's out there. The Dude. Takin' 'er easy for all us sinners. Shoosh." The Stranger

Very simply...and with all due respect to Al Carruth's work on back resonant modes...the resonant or semi-floppy back gives a lot to the player. A very stiff and reflective back projects sound forward more.

I recorded a 1934 Martin D-28 "'bone" set up in a clamping rack and then recorded the guitar I made for Henry Kaiser which had a very stiff Honduras rosewood back with carbon fiber topped braces.   Mic position was indentical, action was pretty close between the two guitars; strings were the same D'Addario Bluegrass set.   The guitar I built was 3 dB hotter into the mic preamp...which translates as twice as loud 11" off the front of the guitar. Mine did not sound particularly loud from behind; the D-28 was pretty hot from playing position.   In neither case was the back being damped at all.   My conclusion matched my theory...that a stiff and reflective back makes a guitar more directional and forces what acoustic energy you are developing forward in a more cardioid pattern.   This is in line with how Smallman, Redgate, et al build classicals for maximum projection.   It's not all about the lattice bracing, a lot is about the polar response pattern of the instrument.   This also matches up to what I've heard when listening to my guitars played purely acoustically in jams...get back 30 feet, and they are really loud.

Makes sense to me. Thanks, Rick.

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Mike

"The Dude abides. I don't know about you but I take comfort in that. It's good knowin' he's out there. The Dude. Takin' 'er easy for all us sinners. Shoosh." The Stranger

Rick,
Is there any one pickup type that may work better as an input for this device than the others? (under bridge patch mounted, under saddle, individual saddle sets or magnetic pickups).

Thanks,

Wade

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Wade
Nashua, NH
http://www.wadefx.com

[QUOTE=Wade S.] Rick,
Is there any one pickup type that may work better as an input for this device than the others? (under bridge patch mounted, under saddle, individual saddle sets or magnetic pickups).

Thanks,

Wade[/QUOTE]

In addition...is there an amp that works best for various situations...Stage, studio, living room?

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JJ
Napa, CA
http://www.DonohueGuitars.com

Rick... this is just amazing.

I don't futz much with the electronics in the acoustic space, but that really sounds fantastic.

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Brock Poling
Columbus, Ohio
http://www.polingguitars.com

Mama is designed to work best with primarily string sensitive pickups...undersaddle or magnetic.   For more complicated systems, it's great on an undersaddle pickup with a second source like a soundboard transducer running in parallel in "faux stereo" so the second source is mixed post Mama Bear.   

Soundboard transducers tend to have a lot of phase information already, and Mama can be overkill.   

The whole point in the beginning was to be able to use more feedback resistant pickups like UST's (which "own" a good 95% of the pickup market...you have to look at all the Taks and Ovations and Washburns and Fishman equipped stuff as the "real world"). These pickups are ubiquitous and are fairly feedback resistant...they just need more complexity and quack reduction...which is what Mama was designed to do in addition to giving you a guitar collection in a box.

Naturally, I like Mama Best with our D-TAR pickups...the Timberline which is what goes into all our Renaissance series of basses and guitars...and the Wavelength which is a much easier to install UST more for the aftermarket. Both pickups have preamps working on an 18 volt supply, and so they have tons of headroom which reduces clipping induced "quack".

I've been involved in pickup design almost as long as I've been a guitar maker (started winding coils in 1969), and to me designing the amplification is no different from designing bracing or whatever.