Mixing speaker sizes

[Guest gazzatriumph]

I have a MAG 300 EVO 3 head and MAG 4 x 10 cab, i contacted Ashdown and asked if was ok to mix MAG 4 x 10 and ABM 115 and they said it would be fine and would add some depth, I have read on other forums that mixing the two can damage the 115 but Ashdown made no mention of this. I have added the ABM 115 and it sounds good.

[Guest gazzatriumph]

If 4 x 10 and 115 is good enough for him its good enough for me.

[Musky]

There's no chance of damaging a 1x15 just because it's used with a 4x10.

If you like the sound the Ashdown 115 and 410 make when used together it's job done.

[Guest gazzatriumph]

[quote name='Musky' timestamp='1349202880' post='1823276']
There's no chance of damaging a 1x15 just because it's used with a 4x10.

If you like the sound the Ashdown 115 and 410 make when used together it's job done.
[/quote]

I spoke to ashdown today and they confirmed what you said

[Wiggybass]

No reason whatsoever why you shouldn't mix any speaker sizes you want so long as you don't go below the minimum impedance (stated in ohms) that your amp will safely drive. Going below that point will make your amp work very hard and likely shorten its life. Most bass amps I've used seem to be happiest working at 4 ohms, and will typically deliver about 25% more power than when working at 8 ohms.

What size you prefer depends a lot on how you use them and what music you play. Fifteens react slower (marginally) but will reproduce lower frequencies (typically regarded as those below about 160 Hz) more readily, so can be good for the deep bass required in dub, reggae, house etc. Tens react faster (marginally) and will not 'go as low' as larger speakers, simply because there is less cardboard moving in and out, but personally I prefer them for reasons of both sound quality and portability. I used an Eden 2 x 10 plus 1 x 15 setup for a while and it was OK, but since I bought my first 4 x 10 I've not really used anything else.

By far the loudest rig I've owned was an original Trace Elliot 300w head with two T-E 4 x 10s, which, despite the modest power of the amp, set off car alarms 50 yards away at half volume outdoors...

[xgsjx]

[quote name='Wiggybass' timestamp='1349207930' post='1823389']
No reason whatsoever why you shouldn't mix any speaker sizes you want so long as you don't go below the minimum impedance (stated in ohms) that your amp will safely drive. Going below that point will make your amp work very hard and likely shorten its life. Most bass amps I've used seem to be happiest working at 4 ohms, and will typically deliver about 25% more power than when working at 8 ohms.

What size you prefer depends a lot on how you use them and what music you play. Fifteens react slower (marginally) but will reproduce lower frequencies (typically regarded as those below about 160 Hz) more readily, so can be good for the deep bass required in dub, reggae, house etc. Tens react faster (marginally) and will not 'go as low' as larger speakers, simply because there is less cardboard moving in and out, but personally I prefer them for reasons of both sound quality and portability. I used an Eden 2 x 10 plus 1 x 15 setup for a while and it was OK, but since I bought my first 4 x 10 I've not really used anything else.

By far the loudest rig I've owned was an original Trace Elliot 300w head with two T-E 4 x 10s, which, despite the modest power of the amp, set off car alarms 50 yards away at half volume outdoors...
[/quote]

Sorry, but quite a bit of that sounds like you've been filled with marketing codswallop.

The main reason you shouldn't mix driver sizes is that you'll get unpredictable results from venue to venue.
As for 15s producing lower frequencies, it's just not true. Marketing gobcrappers would have you believe that, but if you go for decent drivers from the same manufacturer, the specs on how low a frequency it can produce have no baring on driver diameter & more so on how the cab has been designed.

keeping to the same size drivers means you'll get a consistent sound from venue to venue.
I'm not saying don't go for a 4x10 & a 1x15, but you won't really be hearing fully what the 15 is doing as the 4x10 would probably be drowning most of it out.

[chris_b]

Use you ears. If your mixed speaker rig sounds good then it is good. Endof.

[Mr. Foxen]

[quote name='xgsjx' timestamp='1349210433' post='1823454']
keeping to the same size drivers means you'll get a consistent sound from venue to venue.
[/quote]

Not really venue to venue, its more predicable depending on where you stand in relation to the cabs, a venue can still totally sound rubbish, you just have a much better chance of sorting it with eq with a consistent sounding rig over one with weird lumpy sound lobes.

[0175westwood29]

i think the only way you'd cause damage by doing this would be by taking 2 cabs of different rating and putting them together with a high output amp, is this a valid reason for not mixing the cabs?

ie lets say a 200w ampeg 115 and a 410hlf which goes to 500w with an svt pro-6 1100w at 4 ohms, you might not notice the 115 farting due to the volume of the 410? as it would easily take the 550w being put to it? so a newbie to this setup could through inexperiance blow there 15?

i put my 112 hartke with my 1153 trace cab but as there both 300w and my headlite is only 400w, i dnt worry about pushing the cabs but it sounds good so i dnt worry to much about mixing them.

is my logic right?

[Conan]

[quote name='0175westwood29' timestamp='1349254911' post='1823792']
ie lets say a 200w ampeg 115 and a 410hlf which goes to 500w with an svt pro-6 1100w at 4 ohms, you might not notice the 115 farting due to the volume of the 410? as it would easily take the 550w being put to it? so a newbie to this setup could through inexperiance blow there 15?[/quote]

Assuming that the manufacturer's quoted ratings are true (and many aren't), and you ran the amp flat out (why would you EVER need to do that?!?!) then yes - you would almost certainly blow the 115. Most ratings published by manufacturers should be taken with a pinch of salt (Remember the RH450 that is actually 236W?!).

If, however, the 115 and 410 were both rated at, say, 500W - then the assumption is that they would both draw equal power from the amp at any setting. Whether they would put out the same volume (which is far more important) depends on many more parameters like cab design, speaker sensitivity, room temperature, planetary alignment...

[alexclaber]

Yes. If you're using mismatched cabs, always put the one with lower power handling on the top so you have a better chance of hearing it complaining and thus backing off before it dies! The only reason traditional 4x10" + 1x15" stacks get away with the reverse is because they're usually either oversized rigs in small venues so not being pushed that hard, or on big stages where much of the sound is coming from big PA monitors - so not being pushed that hard.

[0175westwood29]

cool glad i got it right, not that im concerned about mixing cabs just wanted to make sure my thinking was correct.

andy

[Wiggybass]

[quote name='xgsjx' timestamp='1349210433' post='1823454'] Sorry, but quite a bit of that sounds like you've been filled with marketing codswallop. The main reason you shouldn't mix driver sizes is that you'll get unpredictable results from venue to venue. As for 15s producing lower frequencies, it's just not true. Marketing gobcrappers would have you believe that, but if you go for decent drivers from the same manufacturer, the specs on how low a frequency it can produce have no baring on driver diameter & more so on how the cab has been designed. keeping to the same size drivers means you'll get a consistent sound from venue to venue. I'm not saying don't go for a 4x10 & a 1x15, but you won't really be hearing fully what the 15 is doing as the 4x10 would probably be drowning most of it out. [/quote]

Hmmm...sorry, simply not true. This is physics and its principles govern all things regardless of marketing.

Let's look beyond crappy, frequency-limited backline and into proper audio systems, like a big modern PA designed to deliver full-range audio to large crowds. In all modern systems the full frequency range is divided electronically into bands, usually four - HF, high-mid, low-mid and LF. HF is always produced by 1" or 2" compression drivers, the mids are usually tens or twelves and the LF is almost always some arrangement of EIGHTEEN inch drivers in ENORMOUS cabinets.

Now, if all speakers could reproduce low frequencies with the same enthusiasm, why go to all this trouble? The answer, of course, is that they don't - they physically can't. The longer the wavelength you're looking to reproduce, the larger the device has to be. At 100Hz (the open G on a concert-tuned bass is 98Hz), the physical wavelength at sea level and 20 degC is 3.4 [i]metres[/i]. Yes, tens will do that but not with the same efficiency of a fifteen of equivalent performance and sensitivity.

This of course all based on a one-speaker to one-speaker comparison. The practical issue comes down to how much cardboard moves in and out when you play, and thus how much air is physically displaced and then picked up by our lugholes. A 4x10 against a single 15 with the same amp power will be louder because it's moving more air but in frequency response terms it will not reproduce low frequencies as efficiently. Which incidentally explains why you're quite right about a 4x10 drowning out a single 15 - for those to balance in terms of physical loudness the 4x10 would have to be turned down a bit.

As for variances between venues, again it depends. Reflex cabs are much more reactive to their surroundings than close or front-ported cabs, that alone would make a lot more difference than the size of drivers they contain. But surely that's what the EQ is for?

[PaulWarning]

[quote name='Wiggybass' timestamp='1349267267' post='1823977']
Hmmm...sorry, simply not true. This is physics and its principles govern all things regardless of marketing.

Let's look beyond crappy, frequency-limited backline and into proper audio systems, like a big modern PA designed to deliver full-range audio to large crowds. In all modern systems the full frequency range is divided electronically into bands, usually four - HF, high-mid, low-mid and LF. HF is always produced by 1" or 2" compression drivers, the mids are usually tens or twelves and the LF is almost always some arrangement of EIGHTEEN inch drivers in ENORMOUS cabinets.

Now, if all speakers could reproduce low frequencies with the same enthusiasm, why go to all this trouble? The answer, of course, is that they don't - they physically can't. The longer the wavelength you're looking to reproduce, the larger the device has to be. At 100Hz (the open G on a concert-tuned bass is 98Hz), the physical wavelength at sea level and 20 degC is 3.4 [i]metres[/i]. Yes, tens will do that but not with the same efficiency of a fifteen of equivalent performance and sensitivity.

This of course all based on a one-speaker to one-speaker comparison. The practical issue comes down to how much cardboard moves in and out when you play, and thus how much air is physically displaced and then picked up by our lugholes. A 4x10 against a single 15 with the same amp power will be louder because it's moving more air but in frequency response terms it will not reproduce low frequencies as efficiently. Which incidentally explains why you're quite right about a 4x10 drowning out a single 15 - for those to balance in terms of physical loudness the 4x10 would have to be turned down a bit.

As for variances between venues, again it depends. Reflex cabs are much more reactive to their surroundings than close or front-ported cabs, that alone would make a lot more difference than the size of drivers they contain. But surely that's what the EQ is for?
[/quote]
bloody hell, don't really understand that, but I do know when I connect my 15" speaker to my 2 x 10" combo it's got more grunt

[Wiggybass]

[quote name='PaulWarning' timestamp='1349268111' post='1823997']
bloody hell, don't really understand that, but I do know when I connect my 15" speaker to my 2 x 10" combo it's got more grunt
[/quote] LOL!!! It surely will, a/ because the amp is now delivering about 25% more power (assuming you're connecting an 8 ohm extension cab to a combo that's fitted with drivers providing an 'internal' load of 8 ohms, thus showing it 4 ohms overall) and b/ because it's moving more cardboard. And that's a good thing!

[xgsjx]

[quote name='Wiggybass' timestamp='1349267267' post='1823977']
Hmmm...sorry, simply not true. This is physics and its principles govern all things regardless of marketing.

Let's look beyond crappy, frequency-limited backline and into proper audio systems, like a big modern PA designed to deliver full-range audio to large crowds. In all modern systems the full frequency range is divided electronically into bands, usually four - HF, high-mid, low-mid and LF. HF is always produced by 1" or 2" compression drivers, the mids are usually tens or twelves and the LF is almost always some arrangement of EIGHTEEN inch drivers in ENORMOUS cabinets.

Now, if all speakers could reproduce low frequencies with the same enthusiasm, why go to all this trouble? The answer, of course, is that they don't - they physically can't. The longer the wavelength you're looking to reproduce, the larger the device has to be. At 100Hz (the open G on a concert-tuned bass is 98Hz), the physical wavelength at sea level and 20 degC is 3.4 [i]metres[/i]. Yes, tens will do that but not with the same efficiency of a fifteen of equivalent performance and sensitivity.

This of course all based on a one-speaker to one-speaker comparison. The practical issue comes down to how much cardboard moves in and out when you play, and thus how much air is physically displaced and then picked up by our lugholes. A 4x10 against a single 15 with the same amp power will be louder because it's moving more air but in frequency response terms it will not reproduce low frequencies as efficiently. Which incidentally explains why you're quite right about a 4x10 drowning out a single 15 - for those to balance in terms of physical loudness the 4x10 would have to be turned down a bit.

As for variances between venues, again it depends. Reflex cabs are much more reactive to their surroundings than close or front-ported cabs, that alone would make a lot more difference than the size of drivers they contain. But surely that's what the EQ is for?
[/quote]

Have a wee read at these & things might make a little more sense to you.

http://barefacedbass.com/technical-information/speaker-size-frequency-response.htm

http://billfitzmaurice.info/forum/viewforum.php?f=10&sid=239e993b6a548da81514b45176b314cb

Smaller drivers give a better dispersion than larger ones. 2 10" drivers vertically arranged in a cab the same size as a single 15" will give out a better dispersion. It's nothing to do with driver diameter on how low it can go, but how much it can move.

The reason behind 15's & 18s is that cabs are cheaper to produce with a single driver.

[Wiggybass]

[quote name='xgsjx' timestamp='1349273161' post='1824084']
Have a wee read at these & things might make a little more sense to you.

[url="http://barefacedbass.com/technical-information/speaker-size-frequency-response.htm"]http://barefacedbass...cy-response.htm[/url]

[url="http://billfitzmaurice.info/forum/viewforum.php?f=10&sid=239e993b6a548da81514b45176b314cb"]http://billfitzmauri...514b45176b314cb[/url]

Smaller drivers give a better dispersion than larger ones. 2 10" drivers vertically arranged in a cab the same size as a single 15" will give out a better dispersion. It's nothing to do with driver diameter on how low it can go, but how much it can move.

The reason behind 15's & 18s is that cabs are cheaper to produce with a single driver.
[/quote] Er...when did dispersion enter the conversation? Below 160Hz it's a completely random concept anyway because frequencies below around that are omnidirectional. Dispersion of LF can only be controlled by what's known as 'beam steering' and has nothing whatsoever to do with backline! I'm really sorry, but whoever told you that diameter has nothing to do with the respective driver's frequency response is talking right out of their rear hole.

Also, and again I'm sorry, but the reasoning behind 15s and 18s being cheaper to produce is simply ridiculous. Perhaps using concert sound equipment was a bit esoteric (but that's my background) - let's look at hi-fi, the principles are exactly the same - here's a really simple hi-fi speaker:

[url="http://www.richersounds.com/product/bookshelf-speakers/q-acoustics/2020i/qaco-2020i-gra"]http://www.richersou.../qaco-2020i-gra[/url]

Now, why do you think that it has one driver larger than the other?

And, what exactly is 'better' dispersion anyway? Wider? Narrower? Varies with frequency (which it does btw)?

Edited October 3, 2012 by Wiggybass

[peteb]

[quote name='xgsjx' timestamp='1349273161' post='1824084']


Have a wee read at these & things might make a little more sense to you.

http://barefacedbass.com/technical-information/speaker-size-frequency-response.htm

http://billfitzmaurice.info/forum/viewforum.php?f=10&sid=239e993b6a548da81514b45176b314cb

Smaller drivers give a better dispersion than larger ones. 2 10" drivers vertically arranged in a cab the same size as a single 15" will give out a better dispersion. It's nothing to do with driver diameter on how low it can go, but how much it can move.

The reason behind 15's & 18s is that cabs are cheaper to produce with a single driver.
[/quote]
You do realise that you are arguing with someone who makes his living working with high end pro audio hire / installation companies??

[alexclaber]

That's as may be but Wiggy wouldn't be the first sound engineer who misunderstand some aspects of loudspeakers! This statement suggests a knowledge gap:

"[color=#282828][font=helvetica, arial, sans-serif]As for variances between venues, again it depends. Reflex cabs are much more reactive to their surroundings than close or front-ported cabs, that alone would make a lot more difference than the size of drivers they contain. But surely that's what the EQ is for?[/font][/color]

[font="helvetica, arial, sans-serif"][color="#282828"]Is 'reflex' cabs referring to rear-ported cabs then?[/color][/font]

[Conan]

[quote name='peteb' timestamp='1349276777' post='1824154']
You do realise that you are arguing with someone who makes his living working with high end pro audio hire / installation companies??
[/quote]

Even doctors get it wrong sometimes...

[Wiggybass]

[quote name='alexclaber' timestamp='1349278169' post='1824185']
That's as may be but Wiggy wouldn't be the first sound engineer who misunderstand some aspects of loudspeakers! This statement suggests a knowledge gap:

"[color=#282828][font=helvetica, arial, sans-serif]As for variances between venues, again it depends. Reflex cabs are much more reactive to their surroundings than close or front-ported cabs, that alone would make a lot more difference than the size of drivers they contain. But surely that's what the EQ is for?[/font][/color]

[font=helvetica, arial, sans-serif][color=#282828]Is 'reflex' cabs referring to rear-ported cabs then?[/color][/font]
[/quote] Yes, sorry - to me reflex cabs are rear-ported, so what they're placed in front of makes a big difference. Serves me right for using slang - that's not the true meaning of 'reflex' in this context.

[alexclaber]

But the thing is, as long as you don't block a rear port or place it so close to a boundary that the effective port length is extended, then whether the port is at the front, rear, side, bottom, etc will have no bearing on how the cab interacts with the room.

Larger speakers don't react slower than smaller speakers, in fact cone mass has little effect on transient response until it gets very high - transient response is much more dependent on voicecoil inductance. How low a speaker goes depends on its combination of T/S parameters (RIP Neville Thiele, the T of that, who died on Monday) and how they combine with the parameters of the enclosure. Our current models use various 12" and 15" woofers and the two models that go lowest use 12"s, and the model that goes least low also uses a 12", the 15" models sitting in between. The deepest responding bass cabs I've ever used contained 10"s but they couldn't drive that bass loud enough for my liking. The least bassy cab I've owned contained a 15".

The one constant is the sensitive (i.e. efficiency or loudness per watt), small (enclosure size, not woofer diameter), deep (low frequency extension), pick any two, rule, also known as Hoffman's Iron Law. Note that speaker diameter isn't part of that law!

Edited October 3, 2012 by alexclaber

[alexclaber]

I should add that most of what is perceived as differences in transient response is actually:

1. A lack of treble response (as this is where transients really happen).
2. Excess 'overhang' so not that the speaker starts moving just fine but that it stops moving too slowly, usually due to underdamped motors and poor enclosures with resonant peaks which ring. Technically this is transient response but it's the second half, not the first half!

[Mr. Foxen]

[quote name='Wiggybass' timestamp='1349269917' post='1824036']
LOL!!! It surely will, a/ because the amp is now delivering about 25% more power (assuming you're connecting an 8 ohm extension cab to a combo that's fitted with drivers providing an 'internal' load of 8 ohms, thus showing it 4 ohms overall) and b/ because it's moving more cardboard. And that's a good thing!
[/quote]

25% more power pretty much won't make an audible difference in itself. Whilst the thing about 3db being the smallest perceivable change in spl isn't true, the difference of 3db from double power isn't very much without a simultaneous comparison point, so only a quarter more power is going to be pretty much inaudible.

[Guest gazzatriumph]

[quote name='icastle' timestamp='1313784140' post='1345846']
Yep.

I use the following equation:

X+Y=Z

Where X is 'looks right', Y is 'sounds right' and Z='it is right'
[/quote]
Sounds about right to me