Mixing Cabs

[Phil Starr]

We haven't had one of those rolling debates for a while and i thought I'd kick one off. It was stimulated by a post by @Tradfusion on one of the LfSys Monza threads so anyone not interested in that cab might not have seen it. This is his post edited down:

 

 

"I bought an LFSys Monza about a month ago based on the positive reviews here on BC and I haven't been disappointed! Its a really nicely designed cab,  I already own 2 Barefaced cabs, the Supercompact and a One10 and I love both cabs but sometimes missed the high end sparkle of a tweeter/horn. Naturally enough my next experiment was to pair the Monza with the BF cabs so on a dep gig with a fairly loud classic rock band I brought along my One10 and sat it on top of the Monza and suddenly the magic started to happen, that cab combination is nothing short of amazing, the warmer and naturally bassier One10 combined with the super clean and more hifi Monza seems to hit a sweet spot that to my ears gives me exactly the tones I am looking for from my basses. A mid punch and tight low end as well as a beautiful smooth top end sparkle.I have used this cab combination now on several gigs and have had many compliments on my tone so obviously something is right about it... I haven't gigged the Monza/Supercompact as a pairing yet but I have linked them at home and they sound fantastic together too so that will be my next experiment..."

 

So that got me thinking, what happens when we mix cabs and why is so much of the advice not to do it when clearly it can work so well empirically. Empiricism is the basis of scientific advance so 'suck it and see' is the rational way to go and if theory says 'don't mix cabs' and it works then the theory has to be wrong, doesn't it?

 

Well not quite of course, science experiments work by isolating single variables and working on them one at a time. It gradually models each aspect of interest starting with a single idea and keeps testing ideas until it has a rounded picture of what is going on. With speakers it's  relatively simple system but even so there  are dozens of variables that we can quantify and they all interact so even if we talk about a single speaker in a fixed place in a single room we'd struggle to model the sound completely at all the frequencies.

 

So what does happen when you mix two speakers, and how does that work with what is possibly the simplest example above, mixing two different tens?

 

Well first and most obvious is with two speakers moving air it's going to get louder, quite a lot louder because you are also drawing more power from the amp, if you stick well within the amp's limits then you'll double the power. We like louder sounds so combining cabs immediately sounds better. Adding extra speakers always subjectively sounds better and adding extra cabs and stacking them vertically is probably the most practical way of getting extra sound.

 

The next thing though is that not all cabs will match each other. Electricity takes the easiest route so adding a 16ohm cab and a 4ohm cab will see almost all your amps power going through the four ohm cab. All cabs aren't equally loud either; adding a less efficient 1x15 to an 8x10 isn't going to work well with the poor 15 getting lost behind it's noisy neighbour. Getting a reasonable efficiency match isn't easy either as few cabs come with an accurate db/W rating.

 

Most of the thoughts of cab mixing are confused too, adding a 15 to a 4x10 for more bass. Not all 15's are bass dominant and some 4x10's are very bass heavy. Again not made easy because few bass cabs come with a frequency response chart. You are left to kind of guess (maybe guesstimate) as to how any combination will sound.

 

So there is one other problem of combining cabs. Speakers aren't ever accurate reproducers of sound, their response is never ruler flat and often less so once they are mounted in a cab. As well as the broad frequency response there are dozens of tiny lumps and bumps in their responses, especially in the higher frequencies where the cone starts to flex and for most speakers in the midrange of the bass. these are what give each speaker its characteristic 'sound' or timbre. If there is a bump it will make that note pop out when you play and a dip will pull that note back a little. If the bumps for two speakers exactly align then you'll get extra pop but that almost never happens. Most irregularities won't line up and a few will line up with a dip in a differnt speaker. My experience with mixing speakers is that you almost always get a 'smoother' sound as the timbre of both speakers merge. You'll probably lose some of the character of both speakers when you mix different ones, you may get a new character but frankly it's hard to predict and the only test is to try it. I had that demonstrated many years ago when a friend with more time than money built a cab with 50 mixed speakers salvaged from old TV's, it sounded remarkably good given the rubbish it was built around but vocals were wonderfully smooth.

 

My take on this it that there is nothing at all wrong with mixing cabs so long as you pay attention to having a fairly decent match. You'll need to know something about impedance matching and power distribution but combining two 8ohm cabs is rarely going to cause problems. Mixing cabs of different sizes isn't necessarily going to give you 'extra bass' or 'more top' without a lot more knowledge of the speakers than their diameter  Mixing cabs will probably lose some or all of their character and serve up something different and this is almost unpredictable. If you want more of a sound you love the advice is always to just add more of the same, don't mix, and stack vertically, never next to each other.

 

My advice is never buy a cab just to improve your sound, not because it is 'wrong' to mix but because it is an expensive way of not getting the sound you want. Instead find a cab that does do what you want and sell the cab that doesn't do it for you, buy two if you still need that louder. That approach is going to work out a lot cheaper in the long run. If you have multiple cabs and they are all 8ohms then mix them all you want and see if it works for you. It'll cost you nothing other than time with your bass which is always time well spent. Experimenting is good not bad. Finally stop obsessing about speaker diameters and trust your ears.

 

So come on what are your experiences of mixing cabs.

 

 

 

 

[Chienmortbb]

40 minutes ago, Phil Starr said:

So come on what are your experiences of mixing cabs.

It broke the mixer? 
 

On a serious note, the only caveat I would add is that PA subs should be placed side by side not vertically and definitely not either side of the stage. 

Edited August 21, 2023 by Chienmortbb

[Lozz196]

Very good post Phil, I`ve had a few 210/115 set-ups and in every case to my ears the pair sounded better than each individual cab - the cabs were always from the same brand and range I should add. From there I found that yes better to have one cab I liked the sound of than two that individually lacked so went 412 initially then 410. When I needed a bit more than the 410 I added on a 210 though in all honesty I hardly ever needed this. Again I would only have same brand & range with these. They did sound great but for gigs that size more often than not there was a provided 810. The only other pairing that I did was Barefaced Compact & Midget with again the sum of both sounding better than each on their own.

[Bill Fitzmaurice]

1 hour ago, Phil Starr said:

 why is so much of the advice not to do it when clearly it can work so well

Because as with Forest Gump's box of chocolates you never know what you're going to get. Some combinations work, some don't, and there's no way to know without trying. If you have a shop full of cabs to try that's OK, but otherwise it's not practical. With identical cabs you know what you'll get, and it will be even better from the additional sensitivity with two than with one. On that, virtually any two cabs together will sound better than either on its own, because of the increase in sensitivity and radiating area. Whether two different cabs will sound better than, or even as good as, a matched pair you can only know by trying all of the possible permutations.

Edited August 21, 2023 by Bill Fitzmaurice

[chris_b]

My OCD won't allow me to mix cabs from different manufacturers, but my successful mixes have been a Berg AE112/AE210, AE112/CN212 and a Mesa Boogie 115EV/210EV. I currently pair up Barefaced SC/SM and BB2/SM cabs.

[BigRedX]

The problem with mixing cabs is that the decisions and how good they sound are made standing a couple of feet away, with no regard for what the combination sounds like elsewhere in the venue. Fine if your rig is simply a personal monitor, but potentially not so good for your audience.

[Newfoundfreedom]

6 minutes ago, BigRedX said:

The problem with mixing cabs is that the decisions and how good they sound are made standing a couple of feet away, with no regard for what the combination sounds like elsewhere in the venue. Fine if your rig is simply a personal monitor, but potentially not so good for your audience.

 

Isn't that the case for any cabs, regardless of whether you're mixing them or not? 

 

At long as it sounds good to my ear, I couldn't care less. In larger venues that's the sound man's job anyway. 

 

It's impossible to account for every nuance of sound in any venue. 

 

Personally I've always been a big fan of the 4x10 / 1x15 combination. However, these days my back is much more a fan of one or two lightweight 1x12's. 

 

If anything more than that is needed I'll be DI'd into the PA and the sound out front isn't my monkey. 

 

 

 

 

Edited August 21, 2023 by Newfoundfreedom

[BigRedX]

You'll get greater variations in sound with two different cabs then you will with a single cab or multiple identical cabs.

[chyc]

Nice summary Phil. One thing that you don't mention is the inherent phase delay of speakers. An ideal speaker would have a defined phase delay between the signal and the output. In practice that just doesn't happen, and the delay is frequency dependent, so as well as having an intrinsic EQ curve for sensitivity, the speaker will have a similar curve for phase. Put identical speakers next to each other, and this doesn't matter as whatever the phase delay is at a particular frequency, these all sum across the speakers so the only phase cancellation is by virtue of the speakers' relative placements. Put different speakers next to each other though, and this no longer holds true, and your sound will be different in a similar way that on a J bass the mid scooped sound of both pickups on full don't sound like you would expect of the sum of the two pickups together.

 

Saying all that, as with the case of a J bass, this may not be a bad thing and you may well love the sound from the mismatch. It's just not very predictable.

[Phil Starr]

3 hours ago, Bill Fitzmaurice said:

Because as with Forest Gump's box of chocolates you never know what you're going to get. Some combinations work, some don't, and there's no way to know without trying. If you have a shop full of cabs to try that's OK, but otherwise it's not practical. With identical cabs you know what you'll get, and it will be even better from the additional sensitivity with two than with one. On that, virtually any two cabs together will sound better than either on its own, because of the increase in sensitivity and radiating area. Whether two different cabs will sound better than, or even as good as, a matched pair you can only know by trying all of the possible permutations.

 

I think that is completely fair. We'd be doing nobody any favours advising them to go out and buy a cab without direct experience. The questions we get are usually of the nature  of 'I've been offered (unknown cab) and I want a bit more heft (or other vague term) from my 2x10 which I love. The answer is pretty obviously in that case to buy a second identical cab.

 

If the question is "Can I buy another cab to make up for the shortcomings of my current cab" then the answer is go and listen until you find a cab you do like and part exchange for the one you don't. Nobody should be advising people to spend money which won't do what they want. So we advise them not to waste their money on an untried 'solution' that almost certainly won't work.

 

I think people have extrapolated from that to say mixing cabs is somehow forbidden or technically illiterate. It isn't, but it is not a good way to spend your money.

[Phil Starr]

1 hour ago, chyc said:

Nice summary Phil. One thing that you don't mention is the inherent phase delay of speakers. An ideal speaker would have a defined phase delay between the signal and the output. In practice that just doesn't happen, and the delay is frequency dependent, so as well as having an intrinsic EQ curve for sensitivity, the speaker will have a similar curve for phase. Put identical speakers next to each other, and this doesn't matter as whatever the phase delay is at a particular frequency, these all sum across the speakers so the only phase cancellation is by virtue of the speakers' relative placements. Put different speakers next to each other though, and this no longer holds true, and your sound will be different in a similar way that on a J bass the mid scooped sound of both pickups on full don't sound like you would expect of the sum of the two pickups together.

 

Saying all that, as with the case of a J bass, this may not be a bad thing and you may well love the sound from the mismatch. It's just not very predictable.

Ha ha

 

Thanks for being kind. I did actually start with a paragraph on phase issues, then it grew to two paragraphs including variable path lengths, then I thought about doing something on room acoustics and decided I'd gone critical mass and nobody would want to read it. I decided non-technical was probably better.

[Bill Fitzmaurice]

2 hours ago, BigRedX said:

You'll get greater variations in sound with two different cabs then you will with a single cab or multiple identical cabs.

That's part and parcel of the myth. To some extent it was true 50 years ago, when there was enough difference between the response of, say, fifteens and tens that there could be some benefit to using both. That's when the myth began. But for the last thirty years the only difference between drivers based purely on their size is the angle of midrange dispersion. The larger the driver the narrower the angle. That's why midrange drivers are smaller than woofers, and tweeters are smaller than midranges. It's about dispersion as much as it is about extension.

 

Take the venerable 1x15/4x10 for instance. Time was that 1x15 would probably have had a driver that went lower than tens, especially as the tens were likely guitar drivers. Being guitar drivers they would have gone higher than a bass fifteen. There was some benefit to mixing them, although ideally there would have been a crossover employed. That ideal was seldom present.

 

Flash forward to the mid 90s or later. 4x10s are now loaded with true bass drivers, so they may go just as low as a 1x15. They have more total driver displacement than a 1x15, so not only do they go just as low, they also go louder. The 1x15 has gone from being the anchor to being the weak link in the chain. OTOH the radiating surface of the 4x10 is wider than that of the 1x15, so its midrange dispersion isn't wider than the 1x15, it's narrower. So where's the benefit of using a 1x15/4x10 today? There is none, unless they're at least 30 years old.

[DGBass]

I have a couple of cabs from different manufactures of different era’s, designs, sizes, materials and weights with identical drivers in them( Faital Pro 15PR400). Both these cabs seem to be able to perform in a surprisingly similar way sound wise to the point it’s difficult to really tell them apart individually in a live setting. If anything, the MM is slightly brighter sounding when pushed, and works better in larger rooms, the TE goes all silky smooth when pushed, sounds very even tone wise and works well in either small or large rooms. At low volume which is the only time I’ve tried them together, the tone appears very even from both cabs. Neither looses the other. I suspect that might change slightly at gig volume.  I haven’t used them live together because a) there has been no need because they are sufficiently loud on their own, b) I can’t fit them both in the car at the same time without a major faff. Just for info, the TE is 38 years old, the MM is 40+ years old. Had they been fitted with their original drivers, the differences between them would I’m sure have been much more noticeable when used together or on their own.  So, Identical drivers in different cabs in my experience might go someway to narrow a cab mismatch if the cabs are reasonably similar designs and tunings eg ported + ported or sealed + sealed. The box itself will add colour/affect the sound in some way and as has been said already combinations really need to be tried and tested, preferably at loud volume where I think a cabs true character is revealed.  The TE cab was actually a project to see if i could get the same performance from the bigger MM cab in a (slightly) smaller package. It seems to have worked well and i now have two very similar performing cabs that i'd be confident enough to stack if the occasion came along. If you have mix and match OCD, best look away now. 

 

 

[Bill Fitzmaurice]

I suspect the difference in brightness is related to the amount of internal damping used, if any.

[DGBass]

Yes, both cabs are damped with the same material but the MM does have a litte less of it. Mainly so as not to obstruct the porting mechanism at the rear of the box.

[BassmanPaul]

6 hours ago, Newfoundfreedom said:

At long as it sounds good to my ear, I couldn't care less. In larger venues that's the sound man's job anyway.

 

Personally I've always been a big fan of the 4x10 / 1x15 combination. However, these days my back is much more a fan of one or two lightweight 1x12's. 

With all due respect this is a copout. You are, in essence, downloading what is your responsibility to someone else. What do you do if the PA fails? Are you just going to go home and say 'Ah well'?

 

As for the awful pairing of a 4x10 and a less able 1x15, BFM answered that very ably, as always. LOL

[Bill Fitzmaurice]

1 hour ago, DGBass said:

Yes, both cabs are damped with the same material but the MM does have a litte less of it. Mainly so as not to obstruct the porting mechanism at the rear of the box.

I suspected that. The damping reduces internal reflections back to the cone. Those reflections arrive back at the cone at various degrees of phase, depending on the distance from the cone to the reflecting surface, and the frequency. They can cause both peaks and valleys in the speaker response. Valleys tend to not be particularly audible, but peaks are.

[Downunderwonder]

I mixed brands 115 210.

 

It sounded great.

 

I tried biamping with crossover using the 115 to cover something like 60hz to 120hz and the 210 120 up. There was an extra bit of clarity to be had, loud enough but not as loud if silly loud was required. I reckon two of the 210 would have covered all bases with one amp.

[BassmanPaul]

A pair of 2x10s, Acme B2, are what I use. I guess I should say did as I no longer play. In a vertical '4x10' configuration they worked really well. 

[Chienmortbb]

10 hours ago, Downunderwonder said:

I mixed brands 115 210.

 

It sounded great.

 

I tried biamping with crossover using the 115 to cover something like 60hz to 120hz and the 210 120 up. There was an extra bit of clarity to be had, loud enough but not as loud if silly loud was required. I reckon two of the 210 would have covered all bases with one amp.

I think bi-amping makes the difference. Feeding band limited signals to the two cabs means there is no chance of the usual comb-filtering. For most people they will not use bi-amping and feedin two different cabs from the same amplifier, is the situation for most.

 

Of course is could cause a happy accident. Look art the Jazz bass for example, some people think the sound of the two pickups gives a pleasant sound. Personally I think that rear pickup is a waste of time BUT so many revered bassists say otherwise.

 

So try it by all,Evans, be prepared to be disappointed but you might just strike gold.

 

 

 

[fretmeister]

I've had mixes of different brands and different cone sizes of the same brand.

 

I suppose the poshest different cone set up I had was a Markbass 2x10 and a 1x15. I really liked each when on their own but could never get them sounding great together. The right EQ for one was just not right for the other. I just about preferred the 1x15 over the 2x10. I couldn't change that because the 2x10 was a combo and I didn't have the money to do a full swap cab and amp head at the time.

 

I've also had a Marshall VBC412 with a Harkte 1x15 - that wasn't good either.

 

The others were all the same

 

Pair of Marshall VBC412 - Amazing - but 110lb each cab! Like any big Marshall it had proper wheels on it but the lift over steps and into the car etc was tough!

Pair of Mark Bass Club 1x12 - very nice

Pair of Berg HD112 - Not bad, quite heavy for 1x12 cabs.

Pair of Berg CN112 - Didn't like them. Much lighter than the HD112 but the tone wasn't to my taste.

Pair of Barefaced One10 (well - one of them is a One10T with a tweeter) - Love them. They sound just right to me.

 

My favourite were the Marshalls but they were now a long time ago and I have no idea whether I'd still like them. My playing style has changed a lot in those years, as has my other equipment including basses.

 

I've had single cab rigs too, but that's not relevant to this.

 

 

Edited August 22, 2023 by fretmeister

[Lozz196]

Marshall VBC412 was one of the best cabs I ever had too @fretmeister

[fretmeister]

I did email Marshall to ask about what cones they used in them, or at least the specs for them, but they said they didn't have the specs anymore.

 

Sadly most of the used ones have been thrashed. I doubt I would buy one again simply because of the weight, but it was awesome.

[Phil Starr]

22 minutes ago, fretmeister said:

I've had mixes of different brands and different cone sizes of the same brand.

 

I suppose the poshest different cone set up I had was a Markbass 2x10 and a 1x15. I really liked each when on their own but could never get them sounding great together. The right EQ for one was just not right for the other. I just about preferred the 1x15 over the 2x10. I couldn't change that because the 2x10 was a combo and I didn't have the money to do a full swap cab and amp head at the time.

 

I've also had a Marshall VBC412 with a Harkte 1x15 - that wasn't good either.

 

The others were all the same

 

Pair of Marshall VBC412 - Amazing - but 110lb each cab! Like any big Marshall it had proper wheels on it but the lift over steps and into the car etc was tough!

Pair of Mark Bass Club 1x12 - very nice

Pair of Berg HD112 - Not bad, quite heavy for 1x12 cabs.

Pair of Berg CN112 - Didn't like them. Much lighter than the HD112 but the tone wasn't to my taste.

Pair of Barefaced One10 (well - one of them is a One10T with a tweeter) - Love them. They sound just right to me.

 

My favourite were the Marshalls but they were now a long time ago and I have no idea whether I'd still like them. My playing style has changed a lot in those years, as has my other equipment including basses.

 

I've had single cab rigs too, but that's not relevant to this.

 

 

That's quite a lot of experience and your experience would seem to say that single cabs or pairs of identical cabs have generally worked out better, that makes sense as somebody has at least optimised them. It doesn't rule out the happy accident but gives some idea of what the odds might be.

[fretmeister]

12 minutes ago, Phil Starr said:

That's quite a lot of experience and your experience would seem to say that single cabs or pairs of identical cabs have generally worked out better, that makes sense as somebody has at least optimised them. It doesn't rule out the happy accident but gives some idea of what the odds might be.

 

Some of the single cabs were great, BF Super Twin for example, and some were a bit lacking like the Hartke HyDrive 410. I didn't get the chance to try adding another Hydrive to see what happened.

 

Practically I like a modular set up so I can carry a lower weight when I don't need more cones.

 

The Marshall VBC412 was great on it's own though. Epic as a pair. Interestingly as those are 4ohm cabs I would often use 2 amps at the same time. They were EQ'd differently when I ran a split signal set up with clean deep lows on one and all the drive and FX on the other.

 

Even when EQ-ing them differently they still worked together better than the Markbass 2x10+1x15 set up.

 

Someone with far better understanding of maths than me will have to explain that!