Big E Speakers Part 4 - Quadraphenia

[peterpalmieri]

Good question! The gramma pad foam is 1 -1/2" thick. I know that it's very effective at its intended purpose. I don't know anything about yoga mats. Maybe an A/B comparison is in order?

I wouldn't bother, I tried all sorts of foam pads I had around before getting a gramma pad. It was an instantly recognizable difference and it's been on just about every gig I've done in the last maybe 10 years. Now if someone is trying to make something better that is totally cool.

 

[thumbs&fingers]

Thumbs, have played all versions of the 112? How does it compare to the 18Sound model?

They are all for slightly different applications. One is more for a rounded modernish tone, one for a mid emphasis rock tone, and one for low power tube application b-15ish

 

[3rdcurve]

Where does the new eminence driver land?

 

[bucephylus]

Lemme rephrase... If the purpose of the Gramma pad is acoustic isolation from the floor - wouldn't setting the cab on a (properly sized) piece of yoga mat do the same thing?

Hey Jonathon. Charlie is correct about the mechanical nature of the coupling; but, I'm presuming that is what you meant anyhow. I have some references to some of Greenboy's insightful posts on the topic that I will try to locate when I get home tomorrow.
(Edit: Here is Greenboy's excellent post)
Stage Coupling and Bass Response

For the moment, I would just say that, yes, lots of things can work, and, of course, different materials with different properties have varying levels of performance. I have had gigs where those cheap foam gardening pads were good enough; so, definitely there would be cases where a thickness or two of yoga mat would do the trick. The Gramma pads are pretty well made and stable. They probably work a bit better than a foam mat. Both Charlie and Greenboy had suggested Sorbothane on TB quite a few years back. I more recently started using that material on my pads, which are more designed for portability; and I have to say that material, Sorbothane, has astounding absorption characteristics. Maybe the best that is out there.

As Charlie also mentioned, we would all do well with some actual data to look at. I intend to build a test bed hollow stage to make measurements on in the near future. That might help shed some light on what is better than something else and what might be good enough. I still am not totally certain how to set that test stage up so that the measurements are reproducible; so, I'm thinking about it. All I have for the moment is empirical observations from gig experiences; and that's not very satisfying. That may sound overly cautious, but making measurements that are hard to reproduce is a waste of time. IME.

Guess that's a long winded way of saying that if the yoga mat is working for you, that's great.

As to whether we all need something better or not, I guess that's why TB is a good place to exchange experiences and try to figure out what really works when, and for which gigs. As Steve mentioned, I do have a new scalable pad design (up to large cab capability) in the test stage with one alpha unit out for objective testing. My approach is to work from both sides of what should theoretically provide optimal isolation combined with making measurements to see what is really happening. With any luck, I may be able to better explain the situation some day.

 

[kesslari]

Wow. There you go coming up with cool ideas again. I think you were the first to ask Mike to make the 210 flex a mod, correct?

Aye, that were me...

 

[kesslari]

Paul, Charlie (and others),

Thanks for the well articulated replies. I haven't played on any real "problem stages" for a while so I'm not trying to solve a particular problem - yet. Sounds like the Gramma is good for what it is. For the next couple of weeks I'll play the FlexTop on a tiltback stand, and when I get the 109 I'll figure out what I want to do with both the single cab and the "Flex+".

 

[J.Wolf]

Thanks Kesslari, I'm very interested since I'm considering trying out a 109 (or 2) and flipping the flex mod. Was thinking about 2x 46 instead but I think the 109 is closer to my tone goal.

 

[coyoteboy]

Ive had good results isolating a small combo, a PJB Bass Cub, with an Ampwedge® though i havent isolated a larger cab like my MAS with a pair of them yet.

 

[J.Wolf]

The gramma pad is a must for me, it dramatically improves the performance of everything, including the flex mod.

 

[J.Wolf]

Although in retrospect, and for anybody on the fence, I'd recommend getting a larger 'great gramma' for the flexmod/210, as the cabinets feet barely fit on the regular sized gramma pad.

 

[mntngrown]

Waiting patiently for Charlie to actually measure such things. I have a big chunk of 2" foam that I have used under the 48 and my previous 1515/66 and used other foam between the tube head and cab. I never had an ahaa! moment in the same space on different days with or w/o foam. Never owned a Gamma though

 

[peterpalmieri]

Sorry for the OT on the gramma pad, but it something you notice when you are doing a gig and the subs at the front of stage are going, the keys are playing and the drummers full out. There's a room full of people making noise and the pad separates the giant woof of bass to give you clarity of your notes when standing within 5 feet of the cab, likely less. The rest of it is on FOH guy, I'm not sure how you'd measure all of that.

You can see I have pretty nice room at home, the gramma pad is against the wall currently not under the amp. It's hard to notice a difference in this room even at high volume.

 

[Ewo]

Hey, @peterpalmieri --

I noticed the acoutic treatment on your walls. Was interested in that. I'm waiting for some Acoustimac panels and corner traps to arrive; gonna treat a game room in my house, which my band uses as a practice space. Hoping that will reduce problems with room modes, flutter, and smear. It's just a big mush now, so I'm hoping to get it sounding decent, at least.

Have any advice for me as to placement in the room, or anything else you learned from experience?

 

[peterpalmieri]

Hey, @peterpalmieri --

I noticed the acoutic treatment on your walls. Was interested in that. I'm waiting for some Acoustimac panels and corner traps to arrive; gonna treat a game room in my house, which my band uses as a practice space. Hoping that will reduce problems with room modes, flutter, and smear. It's just a big mush now, so I'm hoping to get it sounding decent, at least.

Have any advice for me as to placement in the room, or anything else you learned from experience?

I used ATS acoustics but there are a number of reasonable small companies that will do a free consultation and room analysis for you.

Also sweet water will do one and filter it through aurelex.

You have to give them room dimensions, where you plan on putting stuff and the intended use.

 

[Wild Rice Chris]

First double bass run with the Mesa D800 and MAS109 this morning.

 

[ric426]

Aww, c'mon. Don't tease us with a photo and no report! How did it sound?

 

[mgrewe12]

Dumb question probably, would elevating the cab on a stand or chair basically do the same as a gramma pad in terms of decoupling?

 

[J.Wolf]

IME, the orientation/elevation of my MAS cabs have much more impact on the overall tone than previous cabs I've owned. My Flex top, on the floor vs on a Gramma vs elevated on a chair or amp stand has a dramatic effect on frequency balance. This could be seen as temperamental or finicky, but I kind of like that I can tailor the inherent sound by knowing how the cab reacts to these orientations.

and as far as orientation, I know that Mike, for example, runs his cabs horizontal (46,112,109) as he prefers the sound this way. I'm not sure if its purely for tone, or dispersion, or both. I haven't had to cross that bridge, as the Flex sits squarely on its longer side.

For those considering a gramma, I would strongly suggest trying one before writing off the concept based on an approximate model. They are designed to reduce coupling and vibration way more than a foam mat (like a yoga mat) can achieve. I know on one level, its a piece of carpeted plywood floated over a couple pieces of acoustic foam, BUT the net result is very effective. Just my .02c

 

[Gab124]

I had a gramma for a while, and although it did work very well they are not well built for heavy duty, and they grab hair and debris on the bottom foam more than I like. To try something different, and I don't know how it will work yet, I ordered some of these;

Amazon.com: Isolate It!: Sorbothane Female Vibration Bumper Mount - 1/4-20 - .85" (H) - 1 3/4" (Dia) 70 Duro - 4 Pack: Home Improvement

They are Sorbothane vibration bumpers with 1/4" threaded mounts; I plan to make a platform an undecided inches off the ground and have these for the feet. Each foot is good for 35-75 pounds - I will paint it with the duratex or equivalent as well to match up to all my cabs.

 

[Wild Rice Chris]

Aww, c'mon. Don't tease us with a photo and no report! How did it sound?

Took a little playing to get comfortable with the D800. It benefits from an fdeck HPF-Pre, where my PUMA 900 doesn't really care. Excellent for bowing, this Easter gig was all arco and a mix of very traditional and modern.

I ran the MAS109 and Mesa D800 with fretless bass on Friday and was very happy with that. Nice, as I haven't felt the desire to play fretless on a gig in several years!