Bass rigs should be a category

[greenboy]

There are plenty of horn/compression driver combinations that'll go pretty low - but the horns need to be larger format. Look at some of the BMS compression drivers - they have a great coaxial neodymium driver that'll go down to as low as 300 Hz if you have a horn that won't cut out that low.

 

[The 0x]

Pretty sweet.

 

[spode master]

Yeah, I can think of top cab designs I'd rather have, for smoother extended response in that direction, end with better dispersion characteristics.

But yeah, there's been a lot of hype about low end in the bass guitar cab world that's totally malarkey. So it's fresh to see that another person is aware of that and what solutions may be for those who really want to hear true low end.

But using such a rig with a well-spec'd PA/subs is a double-edged sword - you end up with all kind of cancellation/phasing issues with another source for the low frequencies that is (unless your stage is very very deep or very very shallow) not ideally located relative to the hopefully well-placed PA subs (mutual coupling through their audio band and on the same timeline being considered desirable).

Then too, on many stages a lot of real low end is problematic for mic/mic-stand isolation, especially as concerns kick drum. So perhaps using cabs with less SPL at the lower frequencies but having more going on with the PA is still a good way to go. Of course, that supposes that good PA is available in the first place. When one isn't I've put my bass-rig subwoofer section on the floor instead of the stage...

Well you sorta opened pandoras box. Bass in an enclosed environment is problematic no matter how you cut it, and will always be a compromise.

I guess the Ideal environment would be outside on the groundplane with no solid reflective surfaces other than the stage (I love outside gigs). Left and right PA sub stacks are problematic also. Ideal would be a central sub cluster infront of the stage. But you would need a rather tall stage. to not obstruct the performers and audience.

Ahh yes sound reproduction is such a compromise, to bad people feel the need to stretch the truth about it to sell a product.

S'master

 

[Passinwind]

Really you use the Caberet/Hardtrucker series!?

Heh, I played in Deadhead bands back then; nuff said! Mine was merely a Cabaret wedge though, not one of the big monsters. One of our "sister bands" actually had a few pieces from the Wall though.

I need to find a driver 10 or an 8 maybe that has strong output down to 80Hz. And a good Tweeter the only problem is that most of them aren't useful until about 3kHz, so polar pattern is all bad. High output tweeters that are useful down to 1k????

Ahh, the standard universal DIY builder's questions! I spent a lot of time at NAMM this weekend beating up reps for those very things. Not sure what's in the QSC 2 X 8 line array boxes (ILA series), but a few of those might be close to what you're asking for. If you want more coloration (maybe a good thing I think), the Audax pro series 6 1/2" driver is pretty cool in the middle of a 3 way box. I've been concentrating on the amp/preamp end of things for the last few years, and using mostly store bought boxes, but I'm hoping to get back to cab building late this year, hopefully.

 

[SubMonkey]

To even have Proportional SPL to some cheesy rock guitarest that likes to turn his/her martial stack up to 11 to get that tone.

This is my new favorite spelling error (I mean that as a compliment)

SM

 

[greenboy]

Well you sorta opened pandoras box. Bass in an enclosed environment is problematic no matter how you cut it, and will always be a compromise.

I guess the Ideal environment would be outside on the groundplane with no solid reflective surfaces other than the stage (I love outside gigs). Left and right PA sub stacks are problematic also.

Unless your venue is huge, yes... I nver play venues large enough to do that, so I always centralize or place them on one end (and maybe even by a wall there). I really don't worry about "ideal" environments anymore, but have found that huge low end on stage and in conflict with PA subs because one isn't either in effective coupling distance nor are they out of the danger zone - well, that can be avoided, and it improves things immensely. It also means one isn't trying to drive their rig's low end components so hard attempting to make some SPL down there when it just ain't gonna happen because of the cancellations. I think a lot of subs get blown this way, and the sonic results aren't good anyway, even when that doesn't happen.

 

[greenboy]

Here's those BMS coax compression drivers:

Invalid Link Removed

Invalid Link Removed

DDS horns:

Invalid Link Removed

 

[spode master]

Here's those BMS coax compression drivers:

Invalid Link Removed

Invalid Link Removed

DDS horns:

Invalid Link Removed

Oh know He didn't

I'm sure the sound techs would run in terror if they saw me lugging in a bass rig with a large format cinema style horn attatched to it.

I'm not so hot on the BMS coaxial driver at the moment. I don't need that sort of ear splitting SPL available.

I don't need any real response beyond 10kHz. My alembic picups Lowpass at 6kHz maximum, and thats a lot better than most pickup manufacturers. I guess I should look for some sort of paper cone driver or perhaps, or something like this.

[Invalid or Expired Link Removed]

I think a 4 driver configuration of someones nice "Musical sounding 10's might be nice" Maybe throw some Cheap motorola Piezo in there to add some extra Twack to the sound. I do Have a couple of old JBL Bullets I've been trying to figure out what to do with.

I've noticed that Linear response isn't exactly what Bass rig manufacturers are going for. And isn't the kind of toneality most players are seeking.

Anyhow nice joke.

S'master

 

[greenboy]

Not a joke, no more than your rig is. Right? I like transparent PA-like rigs for modeling. If it ain't there, you can't add it, but if it is you can always subtract it.

 

[spode master]

Not a joke, no more than your rig is. Right? I like transparent PA-like rigs for modeling. If it ain't there, you can't add it, but if it is you can always subtract it.

Well physical size aside The subs are comparitively as loud as 2 JBL 2225 15's above 50Hz to about 120Hz. Its bellow that counts.

I have used my rig on really large stages, in small bars and outdoors. But I've also used them as a small PA sub. I think 4 of the cabs would make a pretty wicked little PA For extra LFE extension.

Environment certainly does effect the ability to appreciate the rigs ability. I haven't taken them to a venue that I wasn't providing the sound in so I'm either running BT7's FOH or USING my bassrig as the subs for FOH so its win win for me and my Bass unless I'm getting Nasty 1/4 cancelations from various reflective surfaces. Then I just gotta deal with the crap the venue structure dishes out.

I think the best think for clearing up mic Isolation problems is to have the SUBS routed to a seperate buss, so only instruments that have important LF information go to the subs, things like vocal mic rumble and contamination become a non issue.

S'master

 

[alexclaber]

Fascinating thread. Are those subs straightforward ported 2x12" boxes (though in much larger volume and with lower tuning than a typical bass 2x12")?

I totally agree that that rig is not overkill if you want Marshall stack SPL from the bottom octave of a 5-string bass. It's a nightmare getting that much output down there.

I've been using of pair of Acme Low-B2 cabs which are 6dB down at 31Hz and they do a great job at more reasonable volumes. Rather than get in the arms race, I'd rather get the stage volume down, which helps me sing better and seems to really improve the tone of the band.

But if your drummer and guitarist can't play quieter, then you seem to have found a viable solution.

BMS make some nice loud co-ax 12"s and 15"s which would do a good job as your top cab. Otherwise, how about a Kappalite 3015 and an Alpha 8MR, with a suitable passive crossover, for your midbass and up. If you want to go higher you could even use a piezo array - don't knock it until you've tried it. As it is, the side by side 15"s look like an nightmare off-axis!

I'm actually heading in the opposite direction in terms of cab design, concluding that in most venues I'll either have PA sub support and/or boundary reinforcement to up my output below 100Hz. Looking to build a compact lightweight 3-way cab, with 3015LF 15" neo bottom, dual Alpha 8MR 8" midranges, and a piezo array, with passive crossover designed to flatten out the Alpha's response. ~99dB sensitivity but similar response below 100Hz to a typical bass cab, somewhere about -3dB @ 70Hz, -10dB @ 45Hz in half-space (i.e. nowhere near the Acmes' -3dB @ 41Hz, -6dB @ 31Hz).

Alex

 

[alexclaber]

And to those suggesting AccuGroove for deep deep bottom - get real! Although the prices suggest that they can meet their overblown specs, unfortunately physics tells us that they can't, not by a long shot!

Alex

 

[alexclaber]

I have the background of an electronic tech and am also working on a single integrator circuit sumed with a highpass filter to counteract my pickup placements 6dB per octave Bass roll off. If anyone in the forum understands what I'm talking about, and have any thoughts about such a circuit by all means let me know.

Tell me more!

Alex

 

[alexclaber]

I decided to design my own Bi-amped Bass rig since it became imediately obvious that there is really no comercially available, reasonably portable bass cab or subwoofer on the market that is capable of HIGH SPL output bellow 40 or 50Hz (Well not Many). And there certainly are no "full range" bass cabs capable of any High SPL sub bass.

My design goal was a bass rig that could compete with a Marshal stacks SPL down to and Bellow 30Hz. And keep it reasonalbly portable for something capable of of High SPL (124dB @ 30Hz).

According to my sums, a pair of Acme Low-B4 cabs will meet this requirement. 96dB per cab. -6dB @ 31Hz. 700W RMS power handling (according to my models they will take twice that without over-excursion). So a pair of cabs have 93dB sensitivity @ 31Hz. Add 1400W (conservative, they can take a lot more, but that excludes power compression) and I calculate 124.5 dB at low B fundamental.

Use either two Low-B4s, one Low-B4 and two Low-B2s, or four Low-B2s and you have a nicely scalelable, reasonably portable modular rig.

Alex

 

[rockstarbassist]

And to those suggesting AccuGroove for deep deep bottom - get real! Although the prices suggest that they can meet their overblown specs, unfortunately physics tells us that they can't, not by a long shot!

Alex

But Acme's and a bunch of 10's can...?

 

[alexclaber]

But Acme's and a bunch of 10's can...?

Look at the specs again.

Acme Low-B2: 93dB sensitivity, -3dB @ 41Hz, -6dB @ 31Hz
AG Tri-210L: 103dB sensitivity, -3dB @ 39Hz, -6dB @ 35Hz

Notice the 10dB difference in sensitivity claims? The Acme is accurate - I've modelled it. The AccuGroove is better than every 10" woofer Eminence sells - and AG use Eminence woofers. Furthermore, notice how both cabs claim similar low frequency response? How do you get big bottom from a small box? Use a heavy cone (which reduces sensitivity), use a long voice coil (which reduces sensitivity), and tune it low (which reduces mid-bass sensitivity). The Acme does this. The AccuGroove doesn't. It may be loud (though not as loud as the specs claim), but it does not go low.

The story remains true for all the other models. The Whappo Grande in particular is style over substance - its cabinet is FAR too small to give that kind of LF response and sensitivity. But to the untrained ear that wodge of midbass is probably rather impressive...

If you're still unsure, compare the specs of these manufacturers to those of legitimate SR/PA companies' products. Or even better, download WinISD and try and design a cab that is a small, loud and goes as deep as AccuGroove claim theirs do, even using the best drivers available. It is simply impossible.

Alex

 

[Pneuma]

But Acme's and a bunch of 10's can...?

Compare the size. My rough math says the two Acme B4s would have 1.7 times the cone area and 1.4 times the cabinet volume. Assuming similar xmax, and accounting for the sensitivity difference, I'd say the Acme's have a much better shot at those numbers.

P.

 

[rockstarbassist]

Compare the size. My rough math says the two Acme B4s would have 1.7 times the cone area and 1.4 times the cabinet volume. Assuming similar xmax, and accounting for the sensitivity difference, I'd say the Acme's have a much better shot at those numbers.

P.

Well if we're doing speaker cone area size comparison, that's not a fair nor equal evaluation. For a true side by side test, you'd need like 2.65 Whappos vs. 2 Acme 410's to get equal cone area and then do your tests that way if that's what we're discussing.

I don't say yay or nay about Acme's just b/c I've never tried them, so, unless the Accu nay's have tried them in equal comparisons, I'd hold back the mockery just a tad, as you've never seen nor heard what a Whappo pushed with 3400W sounds like...

 

[alexclaber]

Compare the size. My rough math says the two Acme B4s would have 1.7 times the cone area and 1.4 times the cabinet volume. Assuming similar xmax, and accounting for the sensitivity difference, I'd say the Acme's have a much better shot at those numbers.

P.

And that's assuming similar Xmax and similar tuning - neither of which are the case. The Acmes have double the Xmax of the majority of bass cabs, which equates to having four times as much output in the lows - thats 6dB - for a given cone area.

Well if we're doing speaker cone area size comparison, that's not a fair nor equal evaluation. For a true side by side test, you'd need like 2.65 Whappos vs. 2 Acme 410's to get equal cone area and then do your tests that way if that's what we're discussing.

I don't say yay or nay about Acme's just b/c I've never tried them, so, unless the Accu nay's have tried them in equal comparisons, I'd hold back the mockery just a tad, as you've never seen nor heard what a Whappo pushed with 3400W sounds like...

I never was comparing cone area because it's a fallacy.

I'm not disputing that an El Whappo sounds good, goes loud, has bottom - I'm disputing that it can produce 126dB @ 31Hz as the specs claim. It can't. (Note the full-stop aka period).

We know the El Whappo is tuned to ~40Hz. We know that ported cabs roll off at 24dB/octave below the tuning frequency. We know that a cab that small cannot have 102dB sensitivity in the bass region. Bearing in mind all that data I doubt that the El Whappo can get even close to 120dB on the low B fundamental.

Now you may not want that - in fact there are as many cons as there are pros to having that kind of output down there. So why do they insist on making you think that's what you're hearing?

It's like if you bought a car whose speedo said you were doing 150mph when you were really doing 70mph. If you didn't know any better then you'd really struggle to find a new car that could cruise at 150mph because that's what you like to cruise at.

Just a reality check.

Alex

 

[rockstarbassist]

And that's assuming similar Xmax and similar tuning - neither of which are the case. The Acmes have double the Xmax of the majority of bass cabs, which equates to having four times as much output in the lows - thats 6dB - for a given cone area.



I never was comparing cone area because it's a fallacy.

I'm not disputing that an El Whappo sounds good, goes loud, has bottom - I'm disputing that it can produce 126dB @ 31Hz as the specs claim. It can't. (Note the full-stop aka period).

We know the El Whappo is tuned to ~40Hz. We know that ported cabs roll off at 24dB/octave below the tuning frequency. We know that a cab that small cannot have 102dB sensitivity in the bass region. Bearing in mind all that data I doubt that the El Whappo can get even close to 120dB on the low B fundamental.

Now you may not want that - in fact there are as many cons as there are pros to having that kind of output down there. So why do they insist on making you think that's what you're hearing?

It's like if you bought a car whose speedo said you were doing 150mph when you were really doing 70mph. If you didn't know any better then you'd really struggle to find a new car that could cruise at 150mph because that's what you like to cruise at.

Just a reality check.

Alex

Never saying you were, and that's why I was asking in general if that's the comparison being drawn or if we were speaking in generalizations. Also I'd thought we were discussing more the Whappo Grande (21" sub) but both is fine with me.

I guess, and like you were saying, it's getting past the point of what normal people (even like me) understand about freq. response and SPL's, etc.. I wish people would be honest on their specs too, but nobody is that I've ever seen on anything... like MPG- my truck's sticker says 21MPG HWY. I get about 16.

So, anyhow. Too techie for me anymore.