New DIY Mid High (90deg) - AKA PM90

Has anyone compared RCF ND950 1.4 vs BMS 4594he 8/16ohm on HF950 horn?
After all the reading that I've done on the matter, it seems like the BMS has the sweetest VHF sound in the business but an MF that sounds "good sometimes and wrong sometimes". The RCF seems to have a great sound up until the VHF where it sounds "surprisingly good" for being such a large driver. So, sound quality wise they've got different strengths that add up to a somewhat equal sum as a whole, I'd say. YMMV though, of course.

Sound pressure wise it's no doubt that the BMS would have a clear edge in the HF and VHF, but that's where added output is the least needed. In the MF, where added output is the most needed, the BMS would have an edge but it's unclear by how much, given that the sensitivity of both drivers on this specific horn is not known. The sibling driver of the RCF ND950 (named ND940) is used by RCF themselves in one of their own designs, the NX45, and with a low crossover point of 650hz, which is very similar to the crossover point of the PM90. But, how hard do they push it? I don't know. Let's say that they send 50w to it. The BMS can take 150w continuously with zero risk of bashing the diaphragm against the phase plug. That amounts to a difference of about 4.8db, which undoubtedly is a lot. If the BMS has more sensitivity as well, which it probably does, the gap increases even further.

The question in the end boils down to; How much sound pressure do you need? How much cash do you have? How much processing and how many amps do you have?

If cash, amps and processing are all abundant I'd go straight for the DCX464 or the DCX354 with all active crossovers.
 
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Hi all,

We are currently wiring up these cabinets, and I'm curious - is this a tri-amped cabinet? As far as I can see it, we need one amp for the 12" drivers, one for the mid section of the BMS 4594 ND 1.4, and one for the high section of the BMS 4594 ND 1.4. I'm not interested in exploring a passive XO for the 4594.

Any insight here would be appreciated!

Cheers
 
Hi all,

We are currently wiring up these cabinets, and I'm curious - is this a tri-amped cabinet? As far as I can see it, we need one amp for the 12" drivers, one for the mid section of the BMS 4594 ND 1.4, and one for the high section of the BMS 4594 ND 1.4. I'm not interested in exploring a passive XO for the 4594.

Any insight here would be appreciated!

Cheers
Yes - six amplifier channels required if the passive xover is not used.
 
Hello, I'm about to start building this week and had a few quick questions-

1. For larger edm/dub reggae gigs I'd like to try running these with dedicated kickbins running 80-160ish hz (roughly), would it be sensible to create removable plugs for the ports when I do this in order to potentially smooth the response out and clean things up a bit? Would this give me any additional spl in the higher frequencies? I'll be using ndl76 +dcx354

2.has anyone found a nice balanced point to put the pole mount?

Looking forward to the build,

Cheers
 
Hello, I'm about to start building this week and had a few quick questions-

1. For larger edm/dub reggae gigs I'd like to try running these with dedicated kickbins running 80-160ish hz (roughly), would it be sensible to create removable plugs for the ports when I do this in order to potentially smooth the response out and clean things up a bit? Would this give me any additional spl in the higher frequencies? I'll be using ndl76 +dcx354

2.has anyone found a nice balanced point to put the pole mount?

Looking forward to the build,

Cheers
1. The response above 140hz remains exactly the same, so if you cross over higher than that the main difference you get from plugging the ports will be that you will close off the airflow in the chambre and therefore the cooling. So, you'll be better off if you keep the design as is.

2. You have the standard pole mount point in the dropbox file, although the actual point could be somewhat different for every build, depending on if the drivers, grilles, handles and so on are as per the dropbox file or different. https://www.dropbox.com/s/h16is6mbjig6fcy/pm90_current.pdf?e=1&dl=0
 
Hi gang. Looking for a set of 4 60/90 boxes preferred unloaded. In US. Otherwise if anyone knows anyone who can build four of them in the US please also let me know. I have an application that would really benefit from 4 60s

Thx
 
Hello everybody!

Thanks for the promising plans and informative thread... Also thanks to everybody for the friendly manners here, after reading through German-speaking DIY-Audio forums, that's very refreshing :D

I read most of this thread and I still have some questions...


I am building the PM90s in the following configuration:

DCX464-16 with FB464-16
2* NDL76-8
HF950 Horns


For processing I have a dbx-260 and a Behringer DCX2496. I don't have more money for the likes of Lake or ASC processing just yet.

Does anybody happen to have experiences or even settings for IIR filtering, crossovers, EQs and delays on either of the devices?

How did you solve the phasing issues? Does anybody know if the "Polarity/Phase" (4.5.4 in the manual) Setting on the Outs of the DCX2496 can solve them properly?


Thanks for reading this!

Greetings from Leipzig in Germany
Felix
 
Hello everybody!

Thanks for the promising plans and informative thread... Also thanks to everybody for the friendly manners here, after reading through German-speaking DIY-Audio forums, that's very refreshing :D

I read most of this thread and I still have some questions...


I am building the PM90s in the following configuration:

DCX464-16 with FB464-16
2* NDL76-8
HF950 Horns


For processing I have a dbx-260 and a Behringer DCX2496. I don't have more money for the likes of Lake or ASC processing just yet.

Does anybody happen to have experiences or even settings for IIR filtering, crossovers, EQs and delays on either of the devices?

How did you solve the phasing issues? Does anybody know if the "Polarity/Phase" (4.5.4 in the manual) Setting on the Outs of the DCX2496 can solve them properly?


Thanks for reading this!

Greetings from Leipzig in Germany
Felix
Referring to the settings here, it was solved using the allpass filter.
 
Hi was considering using three of the PM60 for a new home theatre LCR but has anyone done this as I would be interested to hearif they were happy with the outcome. I would also add a sub to flank each side of the center speaker.
 
Hi was considering using three of the PM60 for a new home theatre LCR but has anyone done this as I would be interested to hearif they were happy with the outcome. I would also add a sub to flank each side of the center speaker.
Like how many people do you fit in your home theater, 1000? :D
Imho, the PM60 are way to overpowered. It is a PA speaker after all. As for the center: They don't work as well if positioned horizontally, even with the horn rotated. Relatively high noise floor compared to hifi-options, even with the passive crossover. Also, for the budget of three PM60 you could built some high class hifi speakers potent enough for home cinema.
 
Like how many people do you fit in your home theater, 1000? :D
Imho, the PM60 are way to overpowered. It is a PA speaker after all. As for the center: They don't work as well if positioned horizontally, even with the horn rotated. Relatively high noise floor compared to hifi-options, even with the passive crossover. Also, for the budget of three PM60 you could built some high class hifi speakers potent enough for home cinema.
Thanks for the feedback. I’m interested in diying a nice set of HT speakers building up from an initial an LCR 2xsubs and then 8 surround/atmos and 2 more subs. I’ll be processing using an Alt16.

I’ve since seen the PMA60 on this forum. Which look a bit smaller than the Pm60 although my intent is to install LCR behind the AT screen in a baffle wall, so these again may not be suitable due to rear port.

Another alternative for LCR is Curt Campbell’s Uluwatu although I’m quite drawn to JTR 212RTs from what I’ve heard but the diy clone reviews seem to indicate they aren’t hitting the mark.
 
hi people not sure if in not navigating the forum very well but I can't seem to find full build plans for the pm90s. could anyone point me in the right direction to find them. cheers