Daisy chaining cabs with different ohms & cones

[Bill Fitzmaurice]

2 hours ago, Chienmortbb said:

It is hard not to get technical but cone size does matter. It is just that it is one of a number of things that matter.

+1, and where low frequency response goes it doesn't matter very much. This charts three speakers, one loaded with a ten, one a twelve, one a fifteen:

If you were to believe the size matters crowd you'd have to think that the red line is a fifteen, the blue line a twelve, and the green line a ten. You'd be 33% correct. The blue line is a twelve, but the red line is a ten, the green line a fifteen.

[BigRedX]

Al's problem is that he wants definite empirical answers to his questions, but they don't exist because the sound of a cab depends on lots of different things of which the cone size of the driver(s) is just one, and as Bill Fitzmaurice has just shown there isn't necessarily a direct correlation between driver size and frequency response.

And ultimately it may not even matter. @Al Krow what exactly are your cabs for in a live situation? If the bass is going through the PA your choice of cabs is pretty much irrelevant because their contribution to the FoH sound will be negligible.

[Al Krow]

1 hour ago, BigRedX said:

If the bass is going through the PA your choice of cabs is pretty much irrelevant because their contribution to the FoH sound will be negligible.

It's not. 

When I'm going through the "in house" PA at larger venues I'll often not be bothering with back line at all.

PS to answer your Q BRX - I'm using either a BF SC (for smaller gigs) or a VK210LNT (functions).

Edited November 5, 2018 by Al Krow

[Al Krow]

2 hours ago, Bill Fitzmaurice said:

If you were to believe the size matters crowd you'd have to think that the red line is a fifteen, the blue line a twelve, and the green line a ten. You'd be 33% correct. The blue line is a twelve, but the red line is a ten, the green line a fifteen.

Hah! Ok we've sorted out my problem then. To quote UB40 "I am a one in ten" and would naturally get my reds and greens the wrong way around 😎

Edited November 5, 2018 by Al Krow

[BigRedX]

6 minutes ago, Al Krow said:

It's not.

OK in that case you either need all identical cabs, or you need each different sized driver individually crossed over to prevent dispersion inconsistencies. 

[itu]

7 hours ago, Phil Starr said:

Hi Al, it's genuinely complex isn't it?

One of the complexities is that a lot of the 'information' is also advertising. For example your 'well known manufacturer' who is quoting a 15" cab running from 25-2k is (probably) stretching things a little. If the 15 is flat down to 25 Hz and can handle any power it will have to have a very heavy cone and a long throw, both of which would make it very inefficient. More likely it is 10-20dB down at 25 Hz so it is making some sort of sound but just not loud enough for you to hear significantly...

The best way of judging any cab, particularly an instrument cab is by ear.

 

Published figures without any indication of how they are measured aren't always a lot of use. If they use 'honest' rms watts and +/- 3dB frequency figures and so on then they are likely to lose sales to people who use peak figures.

Mr. Starr elegantly points out pretty much the same facts as I have but not as theoretically as I did.

Marketing is one area (this goes to 25 Hz!) and technical facts another (@ -23.5 dB). There are standardized ways of telling efficiency, frequency response, power rating (at 8 ohms!) etc. but not everybody is using those numbers. And this is probably the biggest reason, why people think that a 4 ohm speaker equals far louder system than 8 ohms, when it is far from that. Try to put a one ohm system after your amplifier and turn it up. What happens? Do you get so much more power?

I remember reading a brochure maybe some 20 years ago about a 7.1 home hifi receiver. This big company claimed that the unit can provide 7 x 100 W speaker output. OK, fine, but the input power was 325 W! This would mean that the system could create an additional 375 watts to speaker outputs neglecting the fact that other parts of the receiver need some energy, too. Actually the amplifier section could push 100 watts to ONE SINGLE speaker output at a time. So this is a 7 x 100 W system, isn't it. My 2 x 110 W / 8 ohms amp takes 650 W to push my two speakers.

There are cold, comparable facts and there is marketing hype. My suggestion is also that you go and test the stuff and find the winner by using your own ears.

[Al Krow]

24 minutes ago, itu said:

There are cold, comparable facts and there is marketing hype. My suggestion is also that you go and test the stuff and find the winner by using your own ears.

A great suggestion in theory. But trying to A/B cabs with a full live band is lot more tricky in practice... which is kinda why the question is posed by us to other folk whose experience we're hoping to tap.

8 hours ago, Bill Fitzmaurice said:

Insufficient data. Only by seeing a measured SPL chart can you know what's really going on. If only manufacturers posted them, but none do.

Just as we had ovnilabs testing compressors (which with due respect are a lot less important than great cabs to our sound) it would be amazing if between us there was some way of getting SPL charts produced for a range of cabs?

Ok which of us has an anechoic chamber in their basement and might be up for doing this?  

[itu]

10 minutes ago, Al Krow said:

A great suggestion in theory. But trying to A/B cabs with a full live band is lot more tricky in practice... which is kinda why the question is posed by us to other folk whose experience we're hoping to tap.

Understood. But if you hate the sound "as is", would it be any better live?

[Al Krow]

9 minutes ago, itu said:

Understood. But if you hate the sound "as is", would it be any better live?

I don't think I ever said I hated my sound. Au contraire mon ami: I've actually never been happier with it. I count myself very fortunate to be able to have on tap two excellent heads (DG M900 and Mesa M6) and two excellent cabs (BF SC and VK210) to mix and match.

This thread has, for me, been all about adding to that sound, but doing so in a way that is going to work well, without the faff of buying a cab and then finding it doesn't really work (noise cancelleation etc.). They can be a pain to sell on in terms of time, effort, couriering etc. as you know.

But I've learned a lot along the way due to some great, helpful, posts from fellow BCers  

Edited November 5, 2018 by Al Krow

[Chienmortbb]

Bill. my point was that if all other things are equal then a bigger cone will output more low end than a smaller one. If we look at tyhree drivers form the same series, i.e. Eminence Delta, We can clearly see that the 15" (Red line) goes lower than the 12" (blue) and the 12' goes lower than the 10". Of course that does not take into account  the enclosure size and in this case thye 15" enclosure is 600 litres the 12" is 100 litres  and the 10" is 15 litres.

The fact is though that the  Eminence Delta 10 can never go as low as the Delta 15 in an idealised enclosure. Clearly the Delta series are not state of the art when it comes to low frequency drivers. Cone area is one of the parameters that decide the performance of a low frequency driver but it is not the only one.

 

[Al Krow]

22 minutes ago, Chienmortbb said:

Bill. my point was that if all other things are equal then a bigger cone will output more low end than a smaller one.

This really was the only key point I was trying to make in relation to cone size, from the outset. 

I appreciate I am in the company of far more expert cab design folk than me, but this statement / conclusion ties in with my very basic understanding of the issue. Thank you. 

Does your point still stand if the surface areas of the cones are the same eg you had several 5" cones so that, together, they have the same surface area as a 15"?

[BigRedX]

54 minutes ago, Al Krow said:

This really was the only key point I was trying to make in relation to cone size, from the outset. 

But unfortunately there isn't any direct and absolute correlation between cone size and frequency response as the trace that Bill posted shows.

Yes, a manufacturer can design a range of drivers that will exhibit the characteristics that Chienmortbb's trace shows, but unless you know exactly which drivers are inside your cabs you are far more likely to get the sorts of results that Bill posted.

@Al Krow stop trying to rely on misleading figures and just use your ears.

Edited November 6, 2018 by BigRedX

[Bill Fitzmaurice]

4 hours ago, Chienmortbb said:

Bill. my point was that if all other things are equal then a bigger cone will output more low end than a smaller one.

If we go back to 1965 that scenario was more or less the case. Fender, for instance, used the Jensen C10, C12 and C15, similar in all aspects save cone size and Fs, so the fifteen went lower than the twelve, which went lower than the ten. By 1975 driver options had expanded to the point that one could no longer make any judgement on potential response based on driver size. 

[chris_b]

On 05/11/2018 at 22:11, Al Krow said:

. . . I count myself very fortunate to be able to have on tap two excellent heads (DG M900 and Mesa M6) and two excellent cabs (BF SC and VK210) to mix and match.

This thread has, for me, been all about adding to that sound. . .

Adding to your sound? Easy. Put a Super Midget (8ohm) on top of your SC (8 ohm) and uprate your sound to a whole new level.

[Al Krow]

18 hours ago, chris_b said:

Adding to your sound? Easy. Put a Super Midget (8ohm) on top of your SC (8 ohm) and uprate your sound to a whole new level.

Thanks Chris.

It sound to me that from your own experience, then, that this combination of differently set up 12" BF cabs gives you something "extra" sonically to just going for the more "obvious" second SC cab? Care to elaborate on what you're hearing with this combination?

[JapanAxe]

54 minutes ago, Al Krow said:

Thanks Chris.

It sound to me that from your own experience, then, that this combination of differently set up 12" BF cabs gives you something "extra" sonically to just going for the more "obvious" second SC cab? Care to elaborate on what you're hearing with this combination?

When I used to add a (non-Super) Midget to a (non-Super) Compact for larger gigs, the Midget brought some more upper mids with it. They were designed and intended to work together.

[Jus Lukin]

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Edited March 1, 2022 by Jus Lukin

[chris_b]

1 hour ago, Al Krow said:

It sound to me that from your own experience, then, that this combination of differently set up 12" BF cabs gives you something "extra" sonically to just going for the more "obvious" second SC cab? Care to elaborate on what you're hearing with this combination?

The SC has a full low mid sound and 2 sound fantastic, but the SC isn't designed to go as low or as high as a BB2. Because the SM is a smaller cab it won't go as low as the SC or BB2, but with the tweeter it emphasises the mids to high end. The SC and SM together give you a wider range than 2 SC's and they work very well together. I borrowed an SM from Barefaced and found I preferred the SC/SM combination, but as I had just ordered a Two10 I didn't have the cash for the SM. It is top of my list to run an SM with one of my SC's.

[JapanAxe]

1 hour ago, Jus Lukin said:

If that is the purpose, then your answer is to add an identical cab, as none of the variables will be present.

Or at least have speakers with identical motors - as in the Compact+Midget scenario.

[Al Krow]

Interesting / helpful comments about the SC & Midget combination.

Reading between the lines, what I'm hearing is that SC + Midget is actually an alternative for the BB2 and by proxy the VK 210 LNT (which I already have).

I would agree that the VK 210LNT gives me a better sound than the SC. But given the price differential I would not have expected less. But the SC is just so darned convenient in terms of portability for rehearsals and smaller gigs.

So I can already improve on the SC with the VK 210LNT. It's whether I can improve on the VK (for which read BB2 if you're a BF lover) or is frankly the cost / benefits of doing so, going to be very marginal and not worth the bother?

[chris_b]

1 minute ago, Al Krow said:

Reading between the lines, what I'm hearing is that SC + Midget is actually an alternative for the BB2 and by proxy the VK 210 LNT (which I already have).

Why read between the lines? Just read the lines!

As I posted, neither BF cab or combination is an alternative for the other. They all have strengths and some can combine to become stronger.

[Jus Lukin]

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Edited March 1, 2022 by Jus Lukin

[Al Krow]

1 hour ago, Jus Lukin said:

Al's been around here quite a while and I'm sure he won't mind me making an observation- his MO appears to be to consider every possible aspect of a subject in the hope of being able to refine it down to a stateable rule, or at least rule of thumb.

Yup that's fair and no objection: it's hardly a character assassination!

But it has led me to never really being happier with my overall sound than I am currently. And, from my perspective, it's been great to learn a thing or two along the way (and hopefully that's been true for other lesser BC mortals). 

[Al Krow]

I did reach out to Mark Vanderkley on the subject, so for completeness (and a nice way to round off the thread!) this is what he had to say:

"It is no problem combining different speaker sizes, although I never do that myself.

If you already have a 210LNT and love that one but need more bottom and volume, I would just add another one.

The 115MN6 is a great cab as a stand alone, the 6” in there is very subtle.

 In general there is no right or wrong, it mostly personal taste. I always use two 210LNT cabs for every gig that I do.

Side by side on the floor (not stacked - it is the transmission of low frequencies in all directions), will give you even more low end. But experiment with cabinet placement  and see what it does in different venues.

For just one cab I would recommend the 210LNT."

[Al Krow]

On 09/11/2018 at 12:16, chris_b said:

Why read between the lines? Just read the lines!

As I posted, neither BF cab or combination is an alternative for the other. They all have strengths and some can combine to become stronger.

Chris - am I correct in understanding that your preferred combination is a SM + SC and for you this trumps 2 x SCs or a BB2?