Most Efficient Cabs?

[gusthebass]

I've been looking through the forums here but haven't really found the info I'm after. I know watts are getting cheaper (and lighter!) all the time, but I'm thinking an efficient cab is rarely discussed, but makes a big difference. IMO I need less "loudness" when I've played with an 8x10 than with a 2x10 or a 1x15. I can hear myself better across the stage, and yet I seem not to be as "loud" as with a 2x10 Combo I regularly use - hey, even the keyboarder complained less! This could be due simply to the height of the speaker - nearer to my ear height so I turn it down - but I think that it's a lot to do with membrane area..
.. please don't bite too hard at that! And that 2x10 Combo is normally kickedback to point at my head- an HK Quantam. And along the lines of efficiency I've got 2 1x15s, one old 200W RMS from the 70s/80s, a large box, big front port, EV speaker, made by Craaft - and another modern (basssysteme.de) one that's really small (just larger than the speaker + tweeter), nice and light, also ported and 600W RMS(!yes!). BUT when I use the same amp into these, the big old beast is much louder at the same amp settings - and (as ever, you have to use my ears!) IMO a much better "Bassier" sound - which is why I play the bass in the first place. 'Course you can fiddle with the EQ and wind the amp up more, but I think it shouldn't be necesary to have to do that. I even made a 2 x10 cab with a transmission line system, so a bit over 2M of folded port to get my low freq. levels up.. but didn't really work. I know horns would have to be immense to help us bassers, so that's also out, unless you know different!
So come on you brains out there - thoughts please. And if you're wondering, why?, I'm thinking a lot about getting a lightweight 8x10 (40KG) because of this - there's several speaker outfits over here in Germany all with pretty fanatical followings that seem to make good and lightweight kit- but really I'm meant to want to go small & light - so the industry seems to assure me.. never mind the family!
Thanks in advance, I'm looking forward to a good discussion here - how about a list of sensitivity dB/Watt/1M specs for different speaker layouts & designs, but at a bass applicable 50 Hz or so and not the normally quoted 1KHz?

[Mr. Foxen]

Bigger cabs are more efficient for low end due to physics, but the speaker efficiency and alignment has an effect, ported will have a better low efficiency than a sealed cab of the same size, due to the port reinforcing the sound in the lows. Horn cabs for bass are possible, BFM offers a load of partially horn loaded models, as well as horn subs, but the low efficiency comes at the cost of mids (hence multi way designs). I had a lighweight 6x12 by Tecamp, and it was great, and very light, but I had to sell it when I quit my job. The Barefaced Vintage/Super 15 is made for efficiency, 2x15 with top end speakers.

[Delberthot]

Laney make a nice light(ish) 8x10" at 45kg. I don't know of any that are lighter without paying big money

[Lfalex v1.1]

You'll be unlikely to find sensitivity figures quoted for 1w/1m for 50Hz. It'd make a lot of cabs seem quite poor. Unfortunately, the standard seems to be 1kHz.
For the same reason, you'll rarely see a trace for modulus of impedance issued by a bass cab manufacturer.
I suppose you could always carry out your own measurements, but I don't think the retailers would like you pumping out 50Hz sine-waves in their shops!!!

Remember that the cabinet is very much a victim of
i) The environment it's being used in
ii) Where it is placed in that environment
iii) EQ
iv) The partnering amp
v) The bass you're playing and how you're playing it (with emphasis on pick-ups and EQ again)

Perhaps altering some other variables could help a lot before you invest in a monster cabinet?

[Bill Fitzmaurice]

Every time you double the number of drivers you increase dB per watt sensitivity by 3dB, so yes, an 810 is more sensitive than a 210. You also completely alter the dispersion pattern with an 810 versus 210, especially if you have the 210 with the drivers horizontal. That's the usual alignment, and the worst way to place them.
Accurate, honest SPL figures are simply not available. Most manufacturers couldn't show an SPL chart if they wanted to, because they don't have any.
If you like the 810 sound but don't want to haul one use two 210s stacked placing the drivers on a vertical line. In most cases output will be adequate, and with no drivers horizontally placed dispersion will be better than an 810.

[Prime_BASS]

The Barefaced line are all efficient.

I had a midget and was worrying about that tone:volume thing win getting the super12T.
Alex said that the S12T would be just a loud as the midget with half the power going to it.

Don't know how relevant this is.

[Mr. Foxen]

[quote name='Prime_BASS' post='1218521' date='May 3 2011, 12:55 PM']The Barefaced line are all efficient.[/quote]

Not sure that that is true, the woofer/mid ones are all about using tons of power to move loads of air in a small light package, and the small ones are for being able to take tons of power while still being small. The idea is they have a variety of sets of compromises in the line up.

[Bill Fitzmaurice]

[quote name='Mr. Foxen' post='1218624' date='May 3 2011, 09:32 AM']Not sure that that is true, the woofer/mid ones are all about using tons of power to move loads of air in a small light package, and the small ones are for being able to take tons of power while still being small. The idea is they have a variety of sets of compromises in the line up.[/quote]+1. Long excursion drivers aren't higher in sensitivity than shorter excursion drivers; if anything they're less sensitive, as is the case with the 3015LF. The advantage to them is being able to utilize higher power amps. If you have a lower power amp they won't do you a bit of good, and you're better off using multiple less expensive cabs than one more expensive cab.
The other advantage to high xmax drivers of the Kappalite mold is that they're state of the art with all of their specs, which means they work better in smaller cabs than most older driver models.

[gusthebass]

[quote name='Bill Fitzmaurice' post='1218817' date='May 3 2011, 05:48 PM']+1. Long excursion drivers aren't higher in sensitivity than shorter excursion drivers; if anything they're less sensitive, as is the case with the 3015LF. The advantage to them is being able to utilize higher power amps. If you have a lower power amp they won't do you a bit of good, and you're better off using multiple less expensive cabs than one more expensive cab.
The other advantage to high xmax drivers of the Kappalite mold is that they're state of the art with all of their specs, which means they work better in smaller cabs than most older driver models.[/quote]
So indeed, my experience. And the question then becomes how much more power does your amp actually need to really become "louder" (Higher SPL) with a small new cab instead of a big oldie!?
Then there's this other thing about total membrane area (the 8x10s thing!)- though that could just be due to the increased number of drivers increasing the SPL for the same amp settings.. I'd liken this to playing acoustic bass guitars vs. a double bass - you know one of these works and the other one simply doesn't. Body volume, surface area..?
Carry on please!

[dan670844]

[quote name='gusthebass' post='1218092' date='May 2 2011, 09:40 PM']I've been looking through the forums here but haven't really found the info I'm after. I know watts are getting cheaper (and lighter!) all the time, but I'm thinking an efficient cab is rarely discussed, but makes a big difference. IMO I need less "loudness" when I've played with an 8x10 than with a 2x10 or a 1x15. I can hear myself better across the stage, and yet I seem not to be as "loud" as with a 2x10 Combo I regularly use - hey, even the keyboarder complained less! This could be due simply to the height of the speaker - nearer to my ear height so I turn it down - but I think that it's a lot to do with membrane area..
.. please don't bite too hard at that! And that 2x10 Combo is normally kickedback to point at my head- an HK Quantam. And along the lines of efficiency I've got 2 1x15s, one old 200W RMS from the 70s/80s, a large box, big front port, EV speaker, made by Craaft - and another modern (basssysteme.de) one that's really small (just larger than the speaker + tweeter), nice and light, also ported and 600W RMS(!yes!). BUT when I use the same amp into these, the big old beast is much louder at the same amp settings - and (as ever, you have to use my ears!) IMO a much better "Bassier" sound - which is why I play the bass in the first place. 'Course you can fiddle with the EQ and wind the amp up more, but I think it shouldn't be necesary to have to do that. I even made a 2 x10 cab with a transmission line system, so a bit over 2M of folded port to get my low freq. levels up.. but didn't really work. I know horns would have to be immense to help us bassers, so that's also out, unless you know different!
So come on you brains out there - thoughts please. And if you're wondering, why?, I'm thinking a lot about getting a lightweight 8x10 (40KG) because of this - there's several speaker outfits over here in Germany all with pretty fanatical followings that seem to make good and lightweight kit- but really I'm meant to want to go small & light - so the industry seems to assure me.. never mind the family!
Thanks in advance, I'm looking forward to a good discussion here - how about a list of sensitivity dB/Watt/1M specs for different speaker layouts & designs, but at a bass applicable 50 Hz or so and not the normally quoted 1KHz?[/quote]


Hey Gus greetings from England, would be interesting if you could tell us about all those boutique cab builders in Germany, would be nice to hear from a players perspective. Thanks Dan

[Mr. Foxen]

[quote name='gusthebass' post='1218979' date='May 3 2011, 06:44 PM']So indeed, my experience. And the question then becomes how much more power does your amp actually need to really become "louder" (Higher SPL) with a small new cab instead of a big oldie!?
Then there's this other thing about total membrane area (the 8x10s thing!)- though that could just be due to the increased number of drivers increasing the SPL for the same amp settings.. I'd liken this to playing acoustic bass guitars vs. a double bass - you know one of these works and the other one simply doesn't. Body volume, surface area..?
Carry on please![/quote]

Basically, the nearest you can get to a guide is the sensitivity spec, which is kind of rubbish as supplied by the manufacturer, but is the best you have to go on, unless you want to model the cabinet in WinISD or equivalent using its measurements and knowing what the driver is. From there, every 3db difference means doubling or halving the amp power to make up for the difference. Big oldies tend towards higher sensitivity from the bigness, and this was down to 'watts' being expensive (both in terms of the amps, and the driver's handling).

[gusthebass]

[quote name='dan670844' post='1218997' date='May 3 2011, 07:54 PM']Hey Gus greetings from England, would be interesting if you could tell us about all those boutique cab builders in Germany, would be nice to hear from a players perspective. Thanks Dan[/quote]
In no particular order or preference Flying Music Circus [url="http://fmc-audio.jimdo.com/"]http://fmc-audio.jimdo.com/[/url] , BassSyteme [url="http://www.basssysteme.de/index.htm"]http://www.basssysteme.de/index.htm[/url] BassTown, [url="http://basstown.de/"]http://basstown.de/[/url] and HOS - "House of Speakers" that seem to have lost the website, but you can get them at Musik Schmidt at least [url="http://www.musik-schmidt.de/de/Baesse/Bassverstaerker/Bass-Boxen"]http://www.musik-schmidt.de/de/Baesse/Bass...rker/Bass-Boxen[/url] They are quite into "Tandem" speakers.. There must be others out there, as I said 've got a BassSyteme 15, but I've heard good things about the others I mentioned too. All these sell direct, I don't know how their English is, but they're all happy to chat and advise on the 'phone iMO.
40KG 8x10s... humm!! Or 33KG 6x10?'?!! If we want to get into a NEO/Ferrite discussion.. Oh yes, and "Bass Cabinet" in German is "BassBox(en)" - who'd have thought it!

Cheers,

[Phil Starr]

Hi Gus, great question, or rather questions. It should keep us going for months.

the easiest one to answer is your transmission line question. Although there are some technical controversies over these the whole point is to absorb the rear pressure and to stop it reflecting back to the speaker so you lose all the energy from the rear of the speaker and you have a decent mass of air in the line. Transmission lines promise lower resonance and smooth low end response with good transients but low efficiency.

Older speakers (I used to design speaker cabs back in the early 70's) tended to have limited power handling due to inferior materials available for the voice coil assembly and the expense of amplifier watts. This meant they were designed to be as efficient as possible by packing a lot of voice coil inside as powerful a magnet as you could afford. The cost of this is that excursion (Xmax) was usually very limited. Speakers weren't really designed for bass specifically anyway most of the time. Excursion limiting wasn't a big issue if you were limited by amp power. Thiele's research wasn't widely known about either, and a lot of design was hit and miss, so a lot of speakers were put in cabs that we now recognise as too small resulting in a marked bass hump in the frequency response which made them seem loud and warm sounding. I suspect this could be the reason for the difference between your cabs.

[Bill Fitzmaurice]

[quote name='Phil Starr' post='1219241' date='May 3 2011, 04:57 PM']the easiest one to answer is your transmission line question. Although there are some technical controversies over these the whole point is to absorb the rear pressure and to stop it reflecting back to the speaker so you lose all the energy from the rear of the speaker and you have a decent mass of air in the line. Transmission lines promise lower resonance and smooth low end response with good transients but low efficiency.[/quote]Transmission lines are 1/4 wavelength resonant pipes. The 1/4 wavelength resonant frequency coming out of the terminus acts much like the port in a bass reflex. The line is stuffed with damping material to suppress the harmonics of the pipe frequency. The advantage to a TL is that below the pipe frequency response rolls off at 12dB/octave, like a sealed cab, rather than the 24dB/octave of a bass reflex, so you get sealed cab 'tightness' with reflex efficiency. The downside is that they need that 1/4 wavelength pipe, which is 5.7 feet for 50 Hz, 7 feet for 40Hz. They're just too big to be practical for electric bass.

Edited May 3, 2011 by Bill Fitzmaurice

[Phil Starr]

[quote name='Bill Fitzmaurice' post='1219340' date='May 3 2011, 11:17 PM']Transmission lines are 1/4 wavelength resonant pipes. The 1/4 wavelength resonant frequency coming out of the terminus acts much like the port in a bass reflex. The line is stuffed with damping material to suppress the harmonics of the pipe frequency. The advantage to a TL is that below the pipe frequency response rolls off at 12dB/octave, like a sealed cab, rather than the 24dB/octave of a bass reflex, so you get sealed cab 'tightness' with reflex efficiency. The downside is that they need that 1/4 wavelength pipe, which is 5.7 feet for 50 Hz, 7 feet for 40Hz. They're just too big to be practical for electric bass.[/quote]
I said there was controversy. Strictly speaking what Bill is describing isn't a true transmission line, but it is the only practical version you'll see today and the one the computer models work on. The original transmission line was just as I described an attempt to absorb all the rear radiation with a zero resistance at the far end of the line to prevent pressure being reflected back along the line where it would arrive out of phase with the speaker cone. Lots of magic went into stuffing the line to achieve this. In the 70's people questioned this and said that the cab acted as a reflex cab in exactly the way Bill describes. Supporters of the original theory will point out, quite correctly, that measurement of the output of the port/termination of the line is much lower than you would expect from a reflex port. The computer models don't predict measured bass response particularly well for these speakers. I'm agnostic about this and ultimately a bit sceptical about the claims for transmission lines. there are some nice sounding TL's in the hi fi sphere but I reckon a lot of this is due to a well behaved impedance load and the massive internal cabinetry which cuts down on a lot of cabinet resonance.

In any case Bill is right, there is no real place for TL's in electric bass cabs.

[Beer of the Bass]

Although Euphonic Audio make some good sounding cabs using what they consider to be a transmission line design. Whether they truly are a transmission line or just an alternative type of port, they are effective cabs.

Edited May 4, 2011 by Beer of the Bass

[Phil Starr]

there you are then EA claim that both sets of ideas are true at the same time and their cabs have all the advantages.

[url="http://www.eaamps.com/index.php?p=translines&m=tech"]http://www.eaamps.com/index.php?p=translines&m=tech[/url]

Mind you, there is no way this is a transmission line. the line itself has to have the cross sectional area of the cone at the speaker end to avoid pressure changes and as Bill says is 1/4 wavelength so that's 6 cu ft packed inside a 2 cu ft box. Truly amazing! And 103dB sensitivity at 45-12,000 Hz with no excursion limiting at 200W, obviously the laws of mere physics no longer apply at EA.

[url="http://www.eaamps.com/index.php?p=wizzym&m=products"]http://www.eaamps.com/index.php?p=wizzym&m=products[/url]

These may be great speakers but I wish people would be honest

[david_l_perry]

[quote name='Phil Starr' post='1219524' date='May 4 2011, 09:09 AM']there you are then EA claim that both sets of ideas are true at the same time and their cabs have all the advantages.

[url="http://www.eaamps.com/index.php?p=translines&m=tech"]http://www.eaamps.com/index.php?p=translines&m=tech[/url]

Mind you, there is no way this is a transmission line[/quote]

Indeed....i had a pair of EA CXL112 transmission line cabs, great little cabs, but I had problems with one of the drivers. when I took the driver out and checked out the inside it was very apparant this is not a true transmision line cab (it was just a long shelf port), but more importantly, the '8ohm' cab is loaded with a 4ohm driver.......MY mark bass head kept shutting down with the pair of them and suddently it became obvious why.......it did explain why they are loud '8ohm' cabs....

EA do make good cabs, but they are just not as described......

[Phil Starr]

[quote name='david_l_perry' post='1219538' date='May 4 2011, 09:34 AM']Indeed....i had a pair of EA CXL112 transmission line cabs, great little cabs, but I had problems with one of the drivers. when I took the driver out and checked out the inside it was very apparant this is not a true transmision line cab (it was just a long shelf port), but more importantly, the '8ohm' cab is loaded with a 4ohm driver.......MY mark bass head kept shutting down with the pair of them and suddently it became obvious why.......it did explain why they are loud '8ohm' cabs....

EA do make good cabs, but they are just not as described......[/quote]

In their current literature they describe the cabs as 4/8 ohms, do they have twin voice coils?

[Mr. Foxen]

[quote name='Phil Starr' post='1220359' date='May 4 2011, 10:25 PM']In their current literature they describe the cabs as 4/8 ohms, do they have twin voice coils?[/quote]

Would guess it means you get a choice when you buy, which would sort of explain the wrong driver/label cock up there. But the different voice coils from that shift about the rest of the spec a bit, guessing by a negligible amount?

[gusthebass]

Mind you, there is no way this is a transmission line. the line itself has to have the cross sectional area of the cone at the speaker end to avoid pressure changes and as Bill says is 1/4 wavelength so that's 6 cu ft packed inside a 2 cu ft box. Truly amazing!

So my somewhat different take on the TL idea was to have almost a 1/2 wave line at the lower freqs (where the cab. would naturally be dropping off..), so the air from the back of the speaker arrives at the front large port (via the pipe) in phase with the air at the front of the speaker - hence 1 speaker for free! There are a load of compromises involved, and yes I know how long a lower E, never mind B is, but with wadding you can slow the speed of sound (and reduce efficiency).. and err.. well it didn't really work. Oh well.. I needed a bigger pipe than i used for starters (I had about 1/3-1/2 speaker cone Surface area).. and and and. Too heavy as well with all the wood making up this heavily folded pipe. Now if someone out there is into large Carbon Fibre Composite complex shape moulding and owns a big autoclave.. come on, wood is SO passé these days...

[Bill Fitzmaurice]

[quote name='gusthebass' post='1220622' date='May 5 2011, 04:05 AM']the line itself has to have the cross sectional area of the cone at the speaker end to avoid pressure changes[/quote]It doesn't, just as a reflex port does not have to have the area of the cone.

[quote]with wadding you can slow the speed of sound[/quote]
Not enough to make any difference.
TLs are very misunderstood, and it doesn't help that there are many proponents of so-called mass loaded TLs that aren't TLs at all, they're tall skinny bass reflex cabs. It's all in the impedance. A TL has a single impedance peak, just like a sealed cab. If the cab has dual impedance peaks it's bass reflex.
[quote]These may be great speakers but I wish people would be honest[/quote]Truth in advertising? What a novel concept.