Bill Fitzmaurice says 210 + 115 setup is okay... Please explain

[basslust]

I have an Ashdown MAG300 115 combo, which is a 4 ohm amp combined with an 8 ohm cab, allowing for the connection of an additional 8 ohm speaker. In trying to determine the exact cab that is in the combo, I contacted Ashdown, who clarified which cab it was (MAG 115 Slim, if anyone is wondering), but also recommended that I consider a 2x10 for the extension, as it would "brighten my sound a tad". I thought this was interesting, as virtually every other reference I have seen to this combo being extended with an external cab has also stated the 115 + 210 setup as being superior to the 2x 115 setup. This is obviously at odds with the "same driver" suggestions common on this forum.

Fast forward to today, and I found this post:

[...] BTW, it's not the 10/15 combination that's so bad, it's the 410/115 that is simply AFU from the get go. The 210/115 combination is OK, but since 210 and 115 cabs aren't the same size and don't stack perfectly and look as pretty as identically sized 410/115 rigs manufacturers don't promote the 210/115 combination. They promote what sells cabs, and what sells cabs is how they look.

I'm thinking maybe there is some misunderstanding on my behalf (and potentially many TBers) of what exactly causes the phase response aberrations if Bill Fitzmaurice himself gives the 210 + 115 the okay here. Can someone clear up why a 410/115 combination would have the phase response issues but not a 210/115?

 

[kesslari]

Note - OK does not mean "good".

 

[Mr. Foxen]

I'm thinking maybe there is some misunderstanding on my behalf (and potentially many TBers) of what exactly causes the phase aberrations if Bill Fitzmaurice himself gives the 210 + 115 the okay here. Can someone clear up why a 410/115 combination would have the phase issues but not a 210/115?

Phase is the minor issue, it just makes a mess of the sound. The 4x10 + 1x15 combo gives a high risk of damage to cab and by extension amp because of the sensitivity and power handling mismatch. Sounding kinda meh is not nearly as bad as breaking your stuff.

 

[smeet]

Phase issues are not resolved, or really any different between a 410/115 and a 210/115 sytem.

Bill probably said that because a 410 can typically take a LOT more power than a 115, and you are likely to blow the 115 before the 410 is breathing hard.
A 210 and a 115 are more likely to be matched up power-wise.

None of this applies to every situation, especially now that we have super-woofers like the 3015LF.
It also does not address phase or sound issues, which may or may not crop up with any mixed fullrange system.

 

[agedhorse]

Because it's possible (if the designer understands phase or time domain analysis) to design perfectly complementary 115 + 210 combinations that are not on;y reasonable from a phase response perspective but also from a power handling and sensitivity perspective.

This doesn't automatically mean that a 115 + 410 cabinet COULDN'T be designed with the same attention to such aspects, but that it is generally much more difficult to do so at a cost that the market is willing to bear, because the 15" driver will need to be a pretty premium driver focused on low frequency extension needs. I have indeed done this for a couple of high profile clients with specific needs, but it's not a defacto standard design approach.

 

[bassjnky1]

The cool thing is that you can do whatever you want.
I provide the sound for my band, so, I have taken the task of learning about sound production seriously. If you don't understand phase alignment and comb filtering you may not know it when you hear it and honestly, humbly, it is all so complex that it is not easy to isolate certain causes and effects. But, I learn something every time I set-up.

When I was first made aware of the speaker mixing problems (here on TB, btw) I was skeptical as well. Why, if it is so bad, is it so common. I set up my own combinations of ten, twelve and fifteen inch speakers to see for myself if I could hear demons. With every pairing of speakers that I could try I heard phase pairings where certain frequencies would be exaggerated and phase cancellations where certain frequencies would partially cancel out. This exercise made me a believer. I don't mix my drivers as a matter of sound. The load mismatch is a whole other matter which is secondary because there are simple ways to deal with that.

So, how many people - players and audience members can recognize this? Not many...but I can and I know what it is when I hear it.

Attention to detail is what separates the pros from the hobbyist.

 

[walterw]

a 4x10 on top of a 15 can be "OK" if it's louder than either cab by itself, makes it easier for you to hear the rig and you know what you're doing so you don't blow it.

the question is just whether it's as good as a comparable-quality matched-cab setup, that's all.

 

[moody]

Surface area is a lot closer matched between 2x10 and 1x15. Assuming similar quality levels of speakers and having the cabinets matched in impedance the power handling levels should be a lot closer as well.

I have a 1x15+2x10 single cabinet. Presumably designed as a complementary grouping. It sounds pretty good to me.

All this however does not mean that you can not do better with matched drivers.

 

[carsbybigd]

If you are using a power amp ( Crown) for your head, and 1 channel goes to your 4x10 and the other channel goes to the 115 does that eliminate the phase alignment ?

 

[Lia_G]

There is also the option, with a 210, to stack it vertically on top of the 115 for a vertical array, so that comb filtering from the 10s is not a problem.

 

[KevInDaBassment]

Because it's possible (if the designer understands phase or time domain analysis) to design perfectly complementary 115 + 210 combinations that are not on;y reasonable from a phase response perspective but also from a power handling and sensitivity perspective.

This doesn't automatically mean that a 115 + 410 cabinet COULDN'T be designed with the same attention to such aspects, but that it is generally much more difficult to do so at a cost that the market is willing to bear, because the 15" driver will need to be a pretty premium driver focused on low frequency extension needs. I have indeed done this for a couple of high profile clients with specific needs, but it's not a defacto standard design approach.

There you go, straight from the (aged)horse's mouth

 

[Korladis]

2x10 paired with a 1x15 is better due to not having the problem of vastly different power handling. It still may have phase issues.

Another advantage is that a 2x10 and 1x15 are much more likely to be similarly loud than a 4x10 and 1x15 are.

 

[walterw]

If you are using a power amp ( Crown) for your head, and 1 channel goes to your 4x10 and the other channel goes to the 115 does that eliminate the phase alignment ?

no.

if anything you risk trying to balance the loudness of the two cabs by ear, sending too much power to the 15 and blowing it sooner.

 

[hintz]

I think Larry Hartke had this 2x10/1x15 combo in mind when he designed these cabs...

As you can see, both cabs are close for wattage and it sounds phenomenal with my 800RB , especially in bi-amp mode when I run the highs into the 2x10 and lows into the 15, like the head/cab's were made for each other....

I bought the cab's as a pair for $300 used, no regrets and to my ears no phase cancellation!!

Edit: I'll also add that I've had the 4x10/1x15 combo a few different times, and only once was there noticeable phase cancellation with a Trace Elliot setup I had, so maybe I was lucky with my other setups??!!

 

[20db pad]

I think Larry Hartke had this 2x10/1x15 combo in mind when he designed these cabs...



Edit: I'll also add that I've had the 4x10/1x15 combo a few different times, and only once was there noticeable phase cancellation with a Trace Elliot setup I had, so maybe I was lucky with my other setups??!!

I used a 4x10 and 1x15 Hartke rig with a GK 800RB for years, just like almost everyone else around NYC in the 80's and 90's. Saw Will Lee use the same setup live dozens of times back then and he sounded great. My old Trace head played well with those cabs, too.

 

[hintz]

I used a 4x10 and 1x15 Hartke rig with a GK 800RB for years, just like almost everyone else around NYC in the 80's and 90's. Saw Will Lee use the same setup live dozens of times back then and he sounded great. My old Trace head played well with those cabs, too.

Very cool!! I'm glad I didn't sell these 2 cabs after my fEARful build, I just love that tone too much

 

[petrus61]

Just in case anyone gives a crap, my GK RBH210 sounds fine on top of my GK Neo115...meaning I have zero issues audibly stressing the speakers and my 700RBII handles the load fine. Perhaps it was serendipitous but after hearing the vast knowledge kicked around on mixing here on TB, it certainly gives me confidence in Bob G's engineering and design. Not so sure if push my luck with a 410 tho..

 

[walterw]

it sounds phenomenal with my 800RB , especially in bi-amp mode when I run the highs into the 2x10 and lows into the 15

that's cool, except crossing the lows out of the 2x10 means it no longer carries its weight as the full range cab it was designed to be, you could replace it with like one 6" mid and get the same output. also, your low end is now only carried by one poor little 15 cab that's itself not a sub, and being 8Ω you're only getting like 200w out of that amp to drive all the low end.

 

[CGremlin]

This doesn't automatically mean that a 115 + 410 cabinet COULDN'T be designed with the same attention to such aspects...

Like maybe a PH1000?

I've never played through one, but they look damned cool in any event.

 

[TMARK]

Used a Trace 15 and an Avatar 210 last night. Head was an Ampeg V4BH. Sounded awesome, but not as good as two Trace 15s.