New DIY Mid High (90deg) - AKA PM90

Stef Smits

Freshman
Apr 4, 2017
88
15
8
At the moment there is no version of the PM60/90 with a passive XO between the LF and MF/HF section. So you have to (at least) bi-amp the cab.

2x12NDL76-16 will give you 8 Ohm nominal when parallel.
1x DCX464-8/16 with a passive XO between the MF and HF will give you either 8 Ohm or 16 Ohm nominal.
So this means you need 2 amp and DSP channels per box. Regarding the passive XO for the DCX, I would look at the B&C FB464 or the blue aran offering. Of course you could also design one on you own if you have the ability.
 

Max Warasila

Graduate
Feb 20, 2013
1,206
65
48
Richmond, VA
At the moment there is no version of the PM60/90 with a passive XO between the LF and MF/HF section. So you have to (at least) bi-amp the cab.

2x12NDL76-16 will give you 8 Ohm nominal when parallel.
1x DCX464-8/16 with a passive XO between the MF and HF will give you either 8 Ohm or 16 Ohm nominal.
So this means you need 2 amp and DSP channels per box. Regarding the passive XO for the DCX, I would look at the B&C FB464 or the blue aran offering. Of course you could also design one on you own if you have the ability.

This is only mostly true. I did attempt it but I was a fetus of an engineer at the time and it was a very bad result.
 

Josh Fernandez

New member
Jul 6, 2020
6
0
1
Perth, Australia
Hi All,

All the parts have arrived for these for us here in Western Australia - just about to embark on the build. We will be using the system for parties of up to 400 people, playing primarily house and techno (some bass stuff always finds its way in there too).

We've yet to decide on a sub to pair with them. We have 4 x B&C 18SW115 - 18" 1700W 8 Ohm drivers ready to go.

Does anyone have any recommendations on a design? We had thought of building some kick-bins after the subs are done too - so if anyone had any suggestions on those that would be very much appreciated.

Many thanks!

P.S. As many have said before - thanks to all that have participated in this thread in such a meaningful way, has been great to learn. Special thanks to Peter himself - can't wait to hear these!
 
Last edited:
Oct 14, 2018
45
15
8
29
Dominica
Hi All,

All the parts have arrived for these for us here in Western Australia - just about to embark on the build. We will be using the system for parties of up to 400 people, playing primarily house and techno (some bass stuff always finds its way in there too).

We've yet to decide on a sub to pair with them. We have 4 x B&C 18SW115 - 18" 1700W 8 Ohm drivers ready to go.

Does anyone have any recommendations on a design? We had thought of building some kick-bins after the subs are done too - so if anyone had any suggestions on those that would be very much appreciated.

Many thanks!

P.S. As many have said before - thanks to all that have participated in this thread in such a meaningful way, has been great to learn. Special thanks to Peter himself - can't wait to hear these!
20210613_181849.jpg
I use my pm60s with these subs... Same 18" drivers as you have from B&C... They work FANTASTIC with those tops... Only one complain i ever get, "bass too loud"... I take that as a compliment... These are the xoc1 version th118
 

Roland Clarke

New member
Feb 22, 2018
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3
Hastings
I
View attachment 209497
I use my pm60s with these subs... Same 18" drivers as you have from B&C... They work FANTASTIC with those tops... Only one complain i ever get, "bass too loud"... I take that as a compliment... These are the xoc1 version th118
I have a variation that I built based on these. Tapped horns are a nice solution. I find a lot of reflex boxes a bit hard going these days. There are some exceptions the L’acoustics KS28 being an example. I also like the dual 21”s KV2 make and their 2.5’s which surprised me as most bandpass boxes suck pretty badly.
 
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Josh Fernandez

New member
Jul 6, 2020
6
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Perth, Australia

This was our first pick at the moment Rob - and what we'd prototyped - was an easy build. Would love to hear feedback of anyone that has used these (even better so if with the PM90).

I have a variation that I built based on these. Tapped horns are a nice solution. I find a lot of reflex boxes a bit hard going these days. There are some exceptions the L’acoustics KS28 being an example. I also like the dual 21”s KV2 make and their 2.5’s which surprised me as most bandpass boxes suck pretty badly.

Perhaps a couple of rookie questions here - but really interested in your perspective here. Why do you feel tapped horns are a good solution for the PM90's? And what do you mean when you say that reflex boxes are a bit hard going these days?
 

Max Warasila

Graduate
Feb 20, 2013
1,206
65
48
Richmond, VA
Perhaps a couple of rookie questions here - but really interested in your perspective here. Why do you feel tapped horns are a good solution for the PM90's? And what do you mean when you say that reflex boxes are a bit hard going these days?
I imagine what he's suggesting is that they seem to be going out of style or seem to be the worse engineering compromise. I actually think that the BR subwoofer is still one of the best compromises overall, but a lot of manufacturers don't give enough box, port, driver, or all of the above.

That's just my perspective though.
 
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Josh Fernandez

New member
Jul 6, 2020
6
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Perth, Australia
I imagine what he's suggesting is that they seem to be going out of style or seem to be the worse engineering compromise. I actually think that the BR subwoofer is still one of the best compromises overall, but a lot of manufacturers don't give enough box, port, driver, or all of the above.

That's just my perspective though.
Appreciate the response Max (and the immense contribution to this design). Do you have any suggestion for BR subs that you'd pair with the PM90?
 

Max Warasila

Graduate
Feb 20, 2013
1,206
65
48
Richmond, VA
Appreciate the response Max (and the immense contribution to this design). Do you have any suggestion for BR subs that you'd pair with the PM90?
I always made a stack with a double 18 BR design underneath. I never pushed the system that far, but I expect that you would find two double 18 subs a side is the balance you'd want for today's music. But, since you only have 4 18SW115, I imagine you'd probably just stick with a single double 18 a side.

There's a build thread on here from a while back which built on a reference design from 18 Sound. I'm actually not a huge fan of what they ended up with. I built something similar but slightly different using surplus JBL2241s, and it was pretty killer. I can try to dig up the plans for those if you want, but they certainly aren't as thorough.

Edit: To be clear - there's no commercial double 18 I'd recommend under a couple grand. For that money, you can build your own unless you need the rider compatibility / brand recognition. In your case, I imagine that's not quite as much of a concern.
 

Josh Fernandez

New member
Jul 6, 2020
6
0
1
Perth, Australia
I always made a stack with a double 18 BR design underneath. I never pushed the system that far, but I expect that you would find two double 18 subs a side is the balance you'd want for today's music. But, since you only have 4 18SW115, I imagine you'd probably just stick with a single double 18 a side.

There's a build thread on here from a while back which built on a reference design from 18 Sound. I'm actually not a huge fan of what they ended up with. I built something similar but slightly different using surplus JBL2241s, and it was pretty killer. I can try to dig up the plans for those if you want, but they certainly aren't as thorough.

Edit: To be clear - there's no commercial double 18 I'd recommend under a couple grand. For that money, you can build your own unless you need the rider compatibility / brand recognition. In your case, I imagine that's not quite as much of a concern.

The current plan was to run with 2 x single 18's each side for now, and eventually move to 4 x single 18's a side - just for ease of movement of the cabinets during bump-in / bump-out. Do you see there being any drawbacks to using singles over double 18's?

The double 18's from 18 Sound look interesting for sure. Won't make you dig up the designs until we're more set however.

And yea - we're not looking to buy commercial double 18's (or singles). Looking to build our own and use the 4 x 18SW115's, powered by an MC2 E100.
 

Max Warasila

Graduate
Feb 20, 2013
1,206
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48
Richmond, VA
Single 18's are more space and weight for the same sound output. There's also some debate about the ports working weirdly differently. I don't honestly have a single 18 design ready to recommend at the moment.
 

Peter van Gils

Freshman
Mar 3, 2013
127
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Netherlands
www.plugingeluid.nl
A single 18 BR cabinet can not keep up with the PM60/90. A tapped horn like the TH118 has much more output (but is twice the size/weight). 4 tapped horns with the 18sw115 would be a perfect fit and will put a smile on your face :-D
I’m using one TH118 with 18sw115 per side (limited by my transport) with PM90 and I feel I could use some more sub (mostly on outdoor events). I think the PM90/TH118 combo is about the most powerful, compact sub-top set that you can build at the moment and that can be handled by one person.
 

Roland Clarke

New member
Feb 22, 2018
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It’s a bit of both. I don’t complain about J subs or KS28’s but these are pretty much top of the tree. Most have problems with port chuff particularly with modern high powered drivers or those that are pushing the envelope. Horn systems, 1/4 Wave systems tend to be more forgiving of being driven harder. As Max pointed out, even the B&C box delivered what he considered mixed results. I’ve heard anecdotal evidence that the 18 sound sub boxes work quite well. The TH118 and derivatives have a good reputation, KV 2 have a great double 21, not what I would have thought about straight away, but they really work, big though. A lot of Tom Danleys subs are well considered. I like the sound of Martin MLA, their subs sit well. Still hear a lot of pretty average sounding boxes though.
 
Oct 14, 2018
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Dominica
A single 18 BR cabinet can not keep up with the PM60/90. A tapped horn like the TH118 has much more output (but is twice the size/weight). 4 tapped horns with the 18sw115 would be a perfect fit and will put a smile on your face :-D
I’m using one TH118 with 18sw115 per side (limited by my transport) with PM90 and I feel I could use some more sub (mostly on outdoor events). I think the PM90/TH118 combo is about the most powerful, compact sub-top set that you can build at the moment and that can be handled by one person.
I aplrove this message... From my picture above ive done events with 1 pm60 and 1 th118 per side... And i have more than enough SPL OUTDOOR.... I highly recommend this combination...
 

Max Warasila

Graduate
Feb 20, 2013
1,206
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48
Richmond, VA
You can design something similar to the KS28, only be ready for extensive testing and probably multiple test cabinets.
That's fairly pessimistic, though it might be true since the KS still has the signature SB28 port chuff, annoyingly. I'm honestly not sure if I'd use the KS28 as a starting point besides the general form factor and driver complement.