4-10's & 2-12's in a PH 810 cabinet?

[Reticle]

I have a Mesa PH 810 cabinet that needs the drivers replaced and that got me thinking..... By all outward appearances the PH 412 & PH 810 are identical, so what would have to be done aside from making a new lower front plate to mount the 12's and some minor rewiring? Would I need to divide the 2 sections?

Sorry if these are elementary questions. I can handle the construction part in my sleep but cabinet design is something I've never really gotten into.

 

[RickenBoogie]

It doesn't make sense to mix the 2 driver sizes. Stick with 10's, and you'll have a solid cab. OEM replacements are best, check with mesa.

 

[dukeisdog]

It doesn't make sense to mix the 2 driver sizes. Stick with 10's, and you'll have a solid cab. OEM replacements are best, check with mesa.

I own a Mesa PH412 and literally the only cab I would trade it for is the PH810. You have yourself a great cab in the 810 and I really don't think it would be worth it switching the 810 to a 412.

 

[Reticle]

It doesn't make sense to mix the 2 driver sizes.

Clearly.......

 

[NKBassman]

I wouldn't touch the PH810. That's a great sounding cab.

 

[dukeisdog]

Clearly.......

Having owned most of the Mesa big cabs, I've gotta say that the PH1200 was my least favourite. Take that with a grain of salt, but do your searching on TB about the cab, lots of guys including myself would prefer the 610/215 to the 1200, and I have side by side compared the 610 to the 1200.

I don't think you could go wrong with ANY of Mesa's cabs, but if I had a choice again, I wouldn't be going with a mixed driver cab.

 

[RickenBoogie]

No need to get touchy. I'm well aware Mesa makes a cab with mixed drivers, and people buy them. But, it's the WORST cab they make. Stick around the TB amps forums. You could learn a thing or two.

 

[swooch]

It doesn't make sense to mix the 2 driver sizes. Stick with 10's, and you'll have a solid cab. OEM replacements are best, check with mesa.

I've tried to read through all the threads on combining different speaker sizes in a rig, but never seen a good run through of the science behind it. I understand phase cancellations and all, but not why different sizes in speakers would result in more of that.

Is there a walkthrough somewhere?

 

[Reticle]

Oh, I'm not getting touchy. You said "It doesn't make sense to mix the 2 driver sizes" and backed that statement up with nothing more than personal opinion. The fact is, People do buy them and depite the fact that they are apparently the "WORST cab they make", some people love them. While I do appreciate your offer to hang around and "learn a thing or two", I simply do not have time to dive into the finer points of enclosure design between playing and building basses. I suppose I am just going to have to go with what I've learned to like in 27 years of playing bass.

Now, back to the topic at hand, I GREATLY appreciate the replies so far, but I am not really asking whether you think I should do it or not. I think the main thing I would like to know is whether or not I should separate the 2 sections and what the baffles look like in the 412.

 

[Bass_Pounder]

I simply do not have time to dive into the finer points of enclosure design between playing and building basses. I suppose I am just going to have to go with what I've learned to like in 27 years of playing bass.

Now, back to the topic at hand, I GREATLY appreciate the replies so far, but I am not really asking whether you think I should do it or not. I think the main thing I would like to know is whether or not I should separate the 2 sections and what the baffles look like in the 412.

If you are not willing to put in the time to learn the science involved in cab design, there is nothing else you learned in your "27 years of playing" that will be of help either.

Best of luck


But here is a free tip:

Yes, the two sections would have to be seperate, and properly sized and tuned to the drivers selected.

Mixing different drivers in the SAME airspace is a recipe for destroying speakers.

 

[dukeisdog]

It's too bad you don't have the opportunity to A/B a brand new PH810 VS a brand new PH1200 because I'm quite certain what most people would typically choose.

The PH810 is IMO one of the best cabs out there right now, and I haven't even played through one. I'm basing my opinion off of my experience with their other PH series cabs. There really is no point to changing the PH810 cab that you have. Get replacements from Mesa and keep it the way it was meant to be. I think you'll be a lot happier in the end with replacements over totally redoing the speaker configuration. If it was a great cab design to begin with, Mesa would most likely offer it commercially.

 

[Reticle]

If you are not willing to put in the time to learn the science involved in cab design, there is nothing else you learned in your "27 years of playing" that will be of help either.

Best of luck


But here is a free tip:

Yes, the two sections would have to be seperate, and properly sized and tuned to the drivers selected.

Mixing different drivers in the SAME airspace is a recipe for destroying speakers.

Ok, since the this is apparently the Amps and Arguments forum.....

First off, I never said that I knew nothing of enclosure design, I was just curious if I was missing anything in what seems to me to be a a quite logical design. No need to be asses about it.

Now, here is what I learned in 5 minutes on the Mesa website..... aside from the baffles, the 412 and the 810 are the SAME FREAKING CABINET. Divided into halves they are virtually identcal (smaller by less than .5 ft²) to the 212 and 410.

So, what made this such a volatile question to ask? With this cabinet divided, what would make it any different from running a 212 and a 410 separately?

 

[Lowactnsatsfctn]

Now, here is what I learned in 5 minutes on the Mesa website..... aside from the baffles, the 412 and the 810 are the SAME FREAKING CABINET. Divided into halves they are virtually identcal (smaller by less than .5 ft²) to the 212 and 410.

If the Out side dimensions are the same, but the number and size of drivers are different, Its not the same internal volume when the displacement of the drivers is accounted for.

The ports, even in the same locations could be different lengths, which could make or break your sound.


By the time you make a new baffle and order 2 speakers, your well in to the cost of a full DIY cab. 2-12s could limit the overall volume output of a 410 if your using the same amp to run them.

Ultimately it is doable ,but with very unpredictable results. Personally, I'd either swap the bad drivers or sell the cab as is and build a 215 for about $60 more than it would cost to mod the existing cab and buy 2 speakers. Then youd have a nice custom built 215 cab. And 15's Rule

 

[Reticle]

If the Out side dimensions are the same, but the number and size of drivers are different, Its not the same internal volume when the displacement of the drivers is accounted for.

The ports, even in the same locations could be different lengths, which could make or break your sound.


By the time you make a new baffle and order 2 speakers, your well in to the cost of a full DIY cab. 2-12s could limit the overall volume output of a 410 if your using the same amp to run them.

Ultimately it is doable ,but with very unpredictable results. Personally, I'd either swap the bad drivers or sell the cab as is and build a 215 for about $60 more than it would cost to mod the existing cab and buy 2 speakers. Then youd have a nice custom built 215 cab. And 15's Rule

Thank you! That is the kind of answer I was looking for!

 

[BassmanPaul]

I was just curious if I was missing anything in what seems to me to be a a quite logical design

The problem is that the design is NOT logical. It's based on a myth that a larger cone can inherently produce more lows than a smaller one. If it were true Phil Jones would be barking up the wrong tree.

Do a search on the PH1200. There are a few requesting help in replacing the blown 15 in that cabinet.

 

[Reticle]

The problem is that the design is NOT logical. It's based on a myth that a larger cone can inherently produce more lows than a smaller one. If it were true Phil Jones would be barking up the wrong tree.

Do a search on the PH1200. There are a few requesting help in replacing the blown 15 in that cabinet.

Wow, the assumptions in this section are unreal! It's like you read the title and the first sentence of the original post. If that's not the case, please point out where I said anything about "more lows".

Anyhow, I'm thinking now that I'm just going to order 16 10's and make an isobaric 1610 to see what kind of reactions that gets.

 

[BassmanPaul]

I read the entire thread. You are the one who introduced the Mesa cabinet into the thread. I made no assumptions whatsoever.

When you pose a question on this site it will be answered to the best of the responders ability. If you choose to ignore that advice because it doesn't agree with your "great idea" so be it. Getting your knickers in a twist will help no one least of all yourself.

The isobaric design is old technology. Better design and capabilities in modern drivers make the concept obsolete.

Edit: Besides how are you going to get the grille back on with all those drivers sticking out???

 

[Reticle]

I read the entire thread. You are the one who introduced the Mesa cabinet into the thread. I made no assumptions whatsoever.

Right... I asked for information concerning some modifications I may or may not make to a Mesa 810 that needs new drivers.

You said, "The problem is that the design is NOT logical. It's based on a myth that a larger cone can inherently produce more lows than a smaller one." It seemed to me that you assumed I was looking for more lows, which I am not. I apologize if I misread it.

When you pose a question on this site it will be answered to the best of the responders ability. If you choose to ignore that advice because it doesn't agree with your "great idea" so be it. Getting your knickers in a twist will help no one least of all yourself.

I asked for information, not advice.

The isobaric design is old technology. Better design and capabilities in modern drivers make the concept obsolete.

I am well aware of this. I guess my sarcasm was lost in type, but I have no intention of putting $1900 worth of speakers in there.

Edit: Besides how are you going to get the grille back on with all those drivers sticking out???

Custom grille made of rebar and chrome chicken wire.

 

[mikeswals]

I own a PH810 as well as a PH212. I have also had to replace a driver in my 810, and right off the bat, I can tell you it will probably be an impedance mismatch if you're wiring all the drivers together, unless you're going to wire separate input jacks for the upper and lower halves.
One other thing to note, I do have to eq my head a little differently depending on which cab I use for the night. So if you're planning on only using one head you'll have to be careful how much lowend you dial up or the 12's will be screaming at you.

 

[1n3]

I asked for information, not advice.

Yeah, that was obvious in your first post.

By the way, I blew a tire on my car. I found a junkyard wheel that has the same bolt pattern, but the tire is smaller. If I add a spacer to the coil spring, that'll compensate, right? I don't want your opinions on whether it's a good idea. I've been driving for 27 years.