the bass player in our band has a bass guitar amplifier (mesa i think)
and (1) 2 x 10" cab and (1) 2 x 12" cab, (the dual 12s gets a little lower)
hes been using both cabs when we rehearse.
im (we) are wondering if its the wrong thing to do?
is it in fact better/cleaner/less distortion/phase risks etc to use either 1 or the other?
or is it absolutely ok to use both at the same time?
and (1) 2 x 10" cab and (1) 2 x 12" cab, (the dual 12s gets a little lower)
hes been using both cabs when we rehearse.
im (we) are wondering if its the wrong thing to do?
is it in fact better/cleaner/less distortion/phase risks etc to use either 1 or the other?
or is it absolutely ok to use both at the same time?
Glad this came up, there's been some misinformation on the interweb that's vaguely irritated me by being not-quite-right.
So here's my attempt to set the record straight, or at least firmly crooked.
Using either cabinet on its own will result in considerably more stress for the drivers, compared to using all the speakers together. For the same output level, distortion will be lower (assuming the amplifier can hack it - being a Mesa, it probably can).
Differing phase between the two cabinets may result in frequency response anomalies, but if everyone (particularly the bassist) is happy with the sound, I see no reason to increase distortion levels because someone somewhere wanted you to buy more of their cabinets.
Remember - for a given voltage, you gain 6dB by putting another cabinet (of equal impedance) in parallel.
To match the level of two cabinets, a single cabinet must absorb 4x the power - the implications of this aren't to be taken lightly.
So here's my attempt to set the record straight, or at least firmly crooked.
Using either cabinet on its own will result in considerably more stress for the drivers, compared to using all the speakers together. For the same output level, distortion will be lower (assuming the amplifier can hack it - being a Mesa, it probably can).
Differing phase between the two cabinets may result in frequency response anomalies, but if everyone (particularly the bassist) is happy with the sound, I see no reason to increase distortion levels because someone somewhere wanted you to buy more of their cabinets.
Remember - for a given voltage, you gain 6dB by putting another cabinet (of equal impedance) in parallel.
To match the level of two cabinets, a single cabinet must absorb 4x the power - the implications of this aren't to be taken lightly.
Both replies have made huge assumptions without verifying them.
What is this equipment? It it all commercial, both the head and the cabs? Is it just a head with 2 output jacks wired straight up with cables to 2 cabinets? Is any part - cable, head or cabs - custom? Any information like an ohm rating on the cabs or an ohm rating on the backplate of the amp?
What is this equipment? It it all commercial, both the head and the cabs? Is it just a head with 2 output jacks wired straight up with cables to 2 cabinets? Is any part - cable, head or cabs - custom? Any information like an ohm rating on the cabs or an ohm rating on the backplate of the amp?
Absolutely OK, and I've known some very experienced and exceptional bass players who did the same thing - as long as the drivers can handle the power and the head is properly loaded no problem. In all likelihood your bass player spent a long time figuring out how to get the sound he was looking for, he may be considerably more sophisticated than you give him credit for. (Or it could be an accident)
Does the rig sound good?
Actually it's not always ok at all.
Depending on the specifics of the speakers and the impedances.
There is a situation where something called "load hogging" can and does occur.
This has to do with impedances and phase angle. Also involved is how much power is available to drive the speakers vs. the power handling of one of the two speaker cabs.
It is easy to see this. Assume for the benefit of discussion that one cabinet has an impedance peak of 32 ohms at 41 Hz. The other cabinet is tuned lower and has an impedance peak of 38 ohms but at 32Hz. Now the bass player hits the low E hard - most of the power goes to the lower impedance speaker. IF that's enough power and it happens enough and the conditions mentioned earlier are met, you fry one or more speakers.
It's a good reason not to use dissimilar drivers in the same enclosure volume - you get the same sorts of issues, only worse.
We're ignoring the idea that he actually got all the drivers wired in phase and also that one box is not two 4 ohm speakers in series and the other 8 ohm drivers in parallel?? Or similar...
Otoh, as mentioned before if it sounds good it is good, according to Count Basie that is...
_-_-bear
Depending on the specifics of the speakers and the impedances.
There is a situation where something called "load hogging" can and does occur.
This has to do with impedances and phase angle. Also involved is how much power is available to drive the speakers vs. the power handling of one of the two speaker cabs.
It is easy to see this. Assume for the benefit of discussion that one cabinet has an impedance peak of 32 ohms at 41 Hz. The other cabinet is tuned lower and has an impedance peak of 38 ohms but at 32Hz. Now the bass player hits the low E hard - most of the power goes to the lower impedance speaker. IF that's enough power and it happens enough and the conditions mentioned earlier are met, you fry one or more speakers.
It's a good reason not to use dissimilar drivers in the same enclosure volume - you get the same sorts of issues, only worse.
We're ignoring the idea that he actually got all the drivers wired in phase and also that one box is not two 4 ohm speakers in series and the other 8 ohm drivers in parallel?? Or similar...
Otoh, as mentioned before if it sounds good it is good, according to Count Basie that is...
_-_-bear
I run a 4x10 cab up top and a single 15 cab on the bottom of my bass rig! this is a very common setup! Both cabs are 8 ohms and I run them in parallel.
My previous cab was an ampeg isovent that had 2x 15's wired push pull and 2x10's. Before that I ran a 2x10 cab with an Acoustic single 18 in a W-bin.
The band I used to work for, the bass player ran FOUR 8x10 ampeg cabs on stage connected to two Ampeg SVT4pro bass amps.
Bass rigs are what ever you want to run as long as you have the impedance figured out...run it!
My previous cab was an ampeg isovent that had 2x 15's wired push pull and 2x10's. Before that I ran a 2x10 cab with an Acoustic single 18 in a W-bin.
The band I used to work for, the bass player ran FOUR 8x10 ampeg cabs on stage connected to two Ampeg SVT4pro bass amps.
Bass rigs are what ever you want to run as long as you have the impedance figured out...run it!
Musicians run all sorts of setups for their monitors
Running the 12's on the bottom with the 10's on the top should, at close range give a very strong "bass boost" since the bottom 12's are off-axis. If he plays close, most of the mids and highs are heard from the 10's. Consider that his ears might have suffered damage over the years--it might be the sound he is looking for.
Ran into one band that had amazing sound--they all ran headphones. Not a single monitor on the stage except a "hot spot" for any announcements by non-band members. One ear was their instrument and the other was the entire mix. One of the reasons the band sounded so clean was no monitors were spilling into the main PA stack.
If he likes the sound of it, it looks cool to the patrons and it is nice to have a redundant rig if one of them blows out. Two equals one, one equals none.
Running the 12's on the bottom with the 10's on the top should, at close range give a very strong "bass boost" since the bottom 12's are off-axis. If he plays close, most of the mids and highs are heard from the 10's. Consider that his ears might have suffered damage over the years--it might be the sound he is looking for.
Ran into one band that had amazing sound--they all ran headphones. Not a single monitor on the stage except a "hot spot" for any announcements by non-band members. One ear was their instrument and the other was the entire mix. One of the reasons the band sounded so clean was no monitors were spilling into the main PA stack.
If he likes the sound of it, it looks cool to the patrons and it is nice to have a redundant rig if one of them blows out. Two equals one, one equals none.
In a hifi system where the goal is to reproduce music and the ideal is a point source, this is true.
But listen to your bass player's bass unplugged. You really don't want to reproduce that. The rules are completely different for making music; in general breaking hifi rules is a good thing, and as long as it sounds good and doesn't blow up too often, it's okay.
Most guitar players favor 2 or 4 speakers in preference to 1 because they like the interference multiple speakers create. The current fad among guitar players is mixing speakers. This creates even more interference and can cause a shift in the position of the "source", a quality highly desired in acoustic instruments like violins, according to recent research.
So, acoustically, your bass player is doing the right thing. Electrically, I think we can trust Mesa to do their thing properly, bear's concerns notwithstanding.
Different size and types of speakers can work OK together.
If the tunings are similar, the phase response can be quite similar too.
I have a 4015LF 15" ported speaker I use for a drum monitor. I have a spare Lab 12 which I loaded in a small box, tuned to the same FB as the 4015LF cabinet.
They look similar in frequency and phase response, and the addition of the Lab 12 adds quite a bit of level.
One "feature" of multiple speakers is the narrowing of dispersion in the top end.
Although the low end may increase as much as 6 dB, the top end will be much reduced off axis. Pointing the 10" (or the 12", whichever top end he prefers) directly at the player will reduce the beaming, and allow him to hear the details that otherwise will be absorbed by his legs and the first row of the audience.
i know that people do this mixing of speakers...
but if you look at what happens to the output of the Mesa that was mentioned when the wrong impedance is presented, perhaps you don't want to do it - unless you or someone else has really looked into the rig.
Tube life can be substantially reduced by putting the wrong or too low of an impedance.
Many "guitar" cabs are set to be "4 ohms"... most players don't know 4 ohms from "4 beers"...
If you halve the impedance and double the cone area then yes you can get 6dB more output... as far as the HF dispersion is concerned that will depend on where the two cabinets are situated WRT each other. Most players are none too scientific about their speaker placement.
Otoh, with the wrong impedance hanging on the output a tube amp you may have just dropped ur power output by 6dB too...?
As I said, IF there is substantial amplifier power available, or if the amp is heavily clipped, AND there are phase shifts and/or impedance differentials or dips there is a risk of "load hogging".
Nowadays most bass speakers are able to handle excessive power levels (heat) and most amplifiers are fairly free from meltdown and oscillations, so you can likely get away with a mismatched set of cabinets on a single amp.
I don't care one way or the other personally, but it is not fair or good to say that running this way is "proper" or not going to or ever cause problems... so I don't think it is good to say that it is "ok" because that is going to be what is picked up on by most people. I'd say you can "get away with it" in many instances.
_-_-bear
but if you look at what happens to the output of the Mesa that was mentioned when the wrong impedance is presented, perhaps you don't want to do it - unless you or someone else has really looked into the rig.
Tube life can be substantially reduced by putting the wrong or too low of an impedance.
Many "guitar" cabs are set to be "4 ohms"... most players don't know 4 ohms from "4 beers"...
If you halve the impedance and double the cone area then yes you can get 6dB more output... as far as the HF dispersion is concerned that will depend on where the two cabinets are situated WRT each other. Most players are none too scientific about their speaker placement.
Otoh, with the wrong impedance hanging on the output a tube amp you may have just dropped ur power output by 6dB too...?
As I said, IF there is substantial amplifier power available, or if the amp is heavily clipped, AND there are phase shifts and/or impedance differentials or dips there is a risk of "load hogging".
Nowadays most bass speakers are able to handle excessive power levels (heat) and most amplifiers are fairly free from meltdown and oscillations, so you can likely get away with a mismatched set of cabinets on a single amp.
I don't care one way or the other personally, but it is not fair or good to say that running this way is "proper" or not going to or ever cause problems... so I don't think it is good to say that it is "ok" because that is going to be what is picked up on by most people. I'd say you can "get away with it" in many instances.
_-_-bear
(drool)
Even though I hate them after rolling countless 8x10's up and down truck ramps, still one of my fav setups.
Unless it's a wall of Eden.
i´m not saying you´re not right but my sub and mains overlap from 40 to 80 hz and i like the results , but i only use a little of the activesub power somewhere between 10 and 20% just to get that nice low end.if i play the sub louder it muddyes the sound , maybe that´s what you´re talking about.
Oh yeah...he would drag 16 full 8x10's on stage but only used four. we tried and tried to talk him into building dummy cabs but nope. he wanted the real deal on stage! talk about dumb!
so believe me when i say i "feel" your pain when talking about 8x10's LOL! I still have the dents, bruises, cuts, scrapes, and scars from loading and unloading those bloody bastards!
Zc
I'm also a bassist and sound guy and my sense about this is that the bass (including its rig) is a sound source. This means that as a bassist, I do my best to have my bass rig cover the full spectrum of what my bass can put out (and believe it or not, this is not all about just the low end... lots of high harmonics, popping sounds etc). So, my full bass rig includes a 2x15 cab and a 2x10 plus horn cab. These are split into two separate amp channels with the big cab handling everything up to about 120 Hz and the small one everything above that. But, that's just the way I do it. For smaller gigs, I'll just bring the 2x10 or a 1x15 practice amp and let the PA handle the bottom end.
When I'm the sound guy, I do my best to reproduce what the bass player wants to hear. So I close mic the rig and DI it. Having a mix of 10's and 12's is not going to hurt the sound I get out front.
When I'm the sound guy, I do my best to reproduce what the bass player wants to hear. So I close mic the rig and DI it. Having a mix of 10's and 12's is not going to hurt the sound I get out front.
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