matched cabs debate

[Al Heeley]

On the other forum there's an interesting debate going on about using 410 and 115 cabs together. Due to different power demands, people are saying they should be different impedance, as it takes different energy to drive 4 x 10" speakers than it does one 15" speaker.
If thats the case then why do all the major companies sell same impedance 410's, 210's and 115's, designed to be used in pairs?
Who is correct?

[Mr. Foxen]

This is where the old speaker properties are not determined by speaker diameter thing comes in.

4 10s will have more speaker area so might have more sensitivity, but this could be offset by being in a sealed box. A 15 in the same size box as the 10s with will have more breathing room, so possibly better sensitivity in the lows, plus 15s are generally in ported cabs, also adding sensitivity in the lows. Really, there are so many other possible factors, it all becomes a bit irrelevant to generalise.

Basically, anyone who makes a statement about speaker size/number affecting the properties of a cab, outside of other considerations, is wrong.

[Musicman20]

What about the TC Electronic RS210/212?

I heard it and it sure sounded good! TC even have a video on how to set it up so the 10s are further back so more of a balanced mix.

Any ideas?

Or is it just science? As in, my Orange rig sounds good, so who cares?!

[Mr. Foxen]

[quote name='Musicman20' post='714028' date='Jan 15 2010, 05:10 PM']What about the TC Electronic RS210/212?

I heard it and it sure sounded good! TC even have a video on how to set it up so the 10s are further back so more of a balanced mix.

Any ideas?

Or is it just science? As in, my Orange rig sounds good, so who cares?![/quote]

What about them?

There are factors other than driver diameter at play.

They don't sound good because there are 10s and 12s,, they sound good because they are designed taking all the factors into account (or at least getting them right inadvertently).

[eddies left thumb]

[quote name='Al Heeley' post='713969' date='Jan 15 2010, 04:25 PM']On the other forum there's an interesting debate going on about using 410 and 115 cabs together. Due to different power demands, people are saying they should be different impedance, as it takes different energy to drive 4 x 10" speakers than it does one 15" speaker.
If thats the case then why do all the major companies sell same impedance 410's, 210's and 115's, designed to be used in pairs?
Who is correct?[/quote]



Regarding the impedance issue the quick answer is they are both possible as long as they don't go lower than the minimum amp impedance (usually 4ohm sometimes 2ohms).

Manufacturers will eg sell 2 x 8ohm cabs for a 4 ohm minimum amp so the full power of the amp can be used
(this assumes wiring is in parallel as normal)
It complicates things if you started using different impedances. A 4ohm and a 8ohm combination will give around 2.6 ohm which is below the 4ohm minimum.
If your amp only goes to 4ohm you'll need a 16ohm and a 8ohm to give 5.3 ohm.
Manufacturers would not want to complicate this by advising or explaing the different impedances

Personally for a 500W rms 4 ohm min amp i'd use a 250W rms 8ohm 15" and a 250W upwards 8ohm for the the 4x10. Then your lowest wattage 15 cab would be ok and the 4x10 although possibly over spec'ed would also be ok. Your amp would also be able to be used fully with max headroom/efficiency/volume as required.

[Al Heeley]

...so you've still got two 8 ohm cabs with differnt power usages due to the physics of shifting different volumes of air. What seems to be implied on the talkbass forum is that an optimal system should have different impedance 4x10 so they both have matched response, i think. I'm starting to lose the plot a little now, I have to admit.

[Musicman20]

[quote name='Mr. Foxen' post='714033' date='Jan 15 2010, 05:14 PM']What about them?

There are factors other than driver diameter at play.

They don't sound good because there are 10s and 12s,, they sound good because they are designed taking all the factors into account (or at least getting them right inadvertently).[/quote]

What about the 'dont ever mix drivers' debate that the cabinet designers always state?!

Thats what I dont understand. If its done correctly, like TC, why not?

Cheers

[Mr. Foxen]

[quote name='Musicman20' post='714148' date='Jan 15 2010, 06:38 PM']What about the 'dont ever mix drivers' debate that the cabinet designers always state?!

Thats what I dont understand. If its done correctly, like TC, why not?

Cheers[/quote]

Its not mixing in the same box, the bit ones will try to suck the little ones in and such like if they are all in the same airspace. Not mixing cabs is cause some cabs are louder and take more power, so the loud one can drown out the weaker one farting out and breaking, or otherwise interfere with each other.

[eddies left thumb]

[quote name='Al Heeley' post='714140' date='Jan 15 2010, 06:31 PM']...so you've still got two 8 ohm cabs with differnt power usages due to the physics of shifting different volumes of air. What seems to be implied on the talkbass forum is that an optimal system should have different impedance 4x10 so they both have matched response, i think. I'm starting to lose the plot a little now, I have to admit.[/quote]


the wattage stated on the cab is not usage but the max its is designed to take
when both cabs are the same impedance and the amp puts out say 200watts, 100watts goes to each cab.

arguably the 4x10 will have a larger surface area than a single 15 so may move more air ie sound/volume slightly.

Its one of those debates than can go on and is really personal preference. i dont think theres much in it but asuming you're are stacking the cab the bottom one will sound different/bassier as its nearer the floor probably making up for any differences.

As you can see I could go on waffling but i really wouldn't worry bout it. Main thing is making sure the cabs impedance is ok for the amp and the power is rated above the output of the amp or at least the same so you don't over power them.

I think they're making a point thats worth a technical debate but in reality lifes too short to worry bout it.



for further reading on imprdace and wattages check out this page [url="http://wiki.basschat.co.uk/info:amps:impedance_and_wattage"]http://wiki.basschat.co.uk/info:amps:impedance_and_wattage[/url]

Edited January 15, 2010 by eddies left thumb

[Bill Fitzmaurice]

[quote name='Al Heeley' post='713969' date='Jan 15 2010, 11:25 AM']If thats the case then why do all the major companies sell same impedance 410's, 210's and 115's, designed to be used in pairs?[/quote]Your question is its own answer. Cab companies build and promote what they think will sell, and the vast majority of players buy their cabs based not upon the engineering within but rather on how they look and who uses them.
Mixing drivers to cover the same bandwidth is not good engineering, but it is successful marketing. If you must succumb to the lures of that marketing a 1x15 and 2x10 are a reasonably good match. A 1x15 and 4x10 isn't.
[quote]Some cabs are made so that they can be mixed, with time aligned, phase coherant and excursion matched cabs, but probably not many.[/quote]I'm not aware of any. If any of the usual sources possessed the technical know-how to do that you can rest assured that they wouldn't keep it a secret. AccuGroove tries to make it seem that way in their ad copy, but their level of technical incompetence was tellingly revealed in the AccuSwitch debacle.
The only significant engineering that I'm aware of where mixed cabs is concerned lies in making the footprints the same for stacking. More than a few 1x15 and 4x10 cabs share not only the same footprint but the exact same cabinet save the number of holes in the baffle. That should set off alarm bells, but curiously it doesn't. The stacking of the two looks very pretty, so it sells.

[Musicman20]

[quote name='Bill Fitzmaurice' post='714317' date='Jan 15 2010, 08:44 PM']Your question is its own answer. Cab companies build and promote what they think will sell, and the vast majority of players buy their cabs based not upon the engineering within but rather on how they look and who uses them.
Mixing drivers to cover the same bandwidth is not good engineering, but it is successful marketing. If you must succumb to the lures of that marketing a 1x15 and 2x10 are a reasonably good match. A 1x15 and 4x10 isn't.
I'm not aware of any. If any of the usual sources possessed the technical know-how to do that you can rest assured that they wouldn't keep it a secret. AccuGroove tries to make it seem that way in their ad copy, but their level of technical incompetence was tellingly revealed in the AccuSwitch debacle.
The only significant engineering that I'm aware of where mixed cabs is concerned lies in making the footprints the same for stacking. More than a few 1x15 and 4x10 cabs share not only the same footprint but the exact same cabinet save the number of holes in the baffle. That should set off alarm bells, but curiously it doesn't. The stacking of the two looks very pretty, so it sells.[/quote]

I remember even Tom Bowlus stating how good the Orange stack was hence I went for the whole thing once I tested it.

Its one of the only 1x15s I really like, and the porting, IMO, is designed very well.

It DOES sound good...honestly.

I tried a few other ideas, and ive tried high end cabs that are right at the top price bracket. The Orange still sounds good in its own way.

I asked TC about their cab matching, and they said all their artists bar a few chose the 210/212 because it just works. They designed them to work how they do. They might not be looking at it from a scientific point of view all the time, but then again, I dont like a sterile perfect uncoloured rig if im honest....Im not keen on the whole 'mini PA' idea. I want a bass rig which can handle finger funk, dirty hardcore punk with lots of grind, and normal rock n roll.

[Al Heeley]

thanks to all for the input - I feel like I've learnt quite a lot today, about technical matters, cab designs and bass players perceptions. These forums are great when they work in this positive way. I can feel a group hug coming on.

[Bill Fitzmaurice]

[quote name='Mr. Foxen' post='714033' date='Jan 15 2010, 12:14 PM']What about them?

There are factors other than driver diameter at play.

They don't sound good because there are 10s and 12s,, they sound good because they are designed taking all the factors into account (or at least getting them right inadvertently).[/quote]
[quote]I asked TC about their cab matching, and they said all their artists bar a few chose the 210/212 because it just works. They designed them to work how they do[/quote]

I seriously doubt that. They look to be reasonably well designed and constructed, but no more so than cabs from a few dozen other companies building bass reflex cabs loaded with Eminence drivers.

There is one fact of audio physics that's never mentioned by any manufacturer: virtually any two cabs together will sound better than either alone. So while the TC 210s and 212s might sound OK together so will most of the 210s and 212s from any other manufacturer. The pertinent question is whether paired TC 210s or 212s would sound better than one of each. That one can only determine by trying all three permutations side by side.

On a side topic the TC 2x cabs do place the drivers vertically, and that is infinitely better than side by side, so that much they got right. But they have a traditional 4x10 in the line up as well, so they're not above sacrificing engineering concerns to the gods of marketing.

Edited January 16, 2010 by Bill Fitzmaurice