PAP Trio 15 Horn Modifications

Kingrex

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I have been wondering about modifying my speakers. Specifically, changing out the horn driver from a Beyma to a BMS. Attached is a link to the BMS.

Overview (bmsspeakers.com)

It look like a great driver to me. I have already done all sorts of crossover component modifications. What I have not done is pull the crossover components off the board and hard wire them. I hear that is another great gain.

Anyhow, has anyone tried changing the driver and to what effect did it have.

Thanks
Rex
 

Kingrex

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Ze'ev is not the right person to talk to about the driver. There isn't any published information on the stock driver. You have to dig hard to figure out what it is. I tacitly mentioned a BMS or Great Plains to him in the past and he was mildly put off by the question.

But really, what manufacturer wants to discuss how to modify their creation. He at least publishes some baffle builds by others, using his stock drivers and crossover.
 

Sablon Audio

Industry Expert, VIP Donor
May 22, 2015
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Many manufacturers are former diy enthusiasts who have taken their passion to a different level. I would have anticipated that he may have considered/evaluated a variety of options or has acted as a sounding post for others considering changes.

No problem if you feel otherwise however this is very much a niche within an already somewhat minority interest hobby.
 

Kingrex

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I bet he has. But those drivers are 25% the cost of a complete shipped speaker. It would be a big impact to pricing to provide them.

And that could add confusion. Now a $10k speaker. Should I get the $7k when its not as good as the $10k. I bet it's a nightmare or sorts to work out your product/price/target market.
 
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Robh3606

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Aug 24, 2010
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I have been wondering about modifying my speakers. Specifically, changing out the horn driver from a Beyma to a BMS. Attached is a link to the BMS.

Overview (bmsspeakers.com)

It look like a great driver to me. I have already done all sorts of crossover component modifications. What I have not done is pull the crossover components off the board and hard wire them. I hear that is another great gain.

Anyhow, has anyone tried changing the driver and to what effect did it have.

Thanks
Rex

Why are you upgrading?? The biggest advantage of the new CD is the lower crossover point. The issue with that is you are going to need a horn large enough to take advantage of the lower bandwidth. Not sure where the crossover is with your speakers is but that horn looks to small to support a 300/400Hz crossover point.

Rob :)
 
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Kingrex

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Why are you upgrading?? The biggest advantage of the new CD is the lower crossover point. The issue with that is you are going to need a horn large enough to take advantage of the lower bandwidth. Not sure where the crossover is with your speakers is but that horn looks to small to support a 300/400Hz crossover point.

Rob :)
I don't know its an upgrade. That is still unknown. Could be a big step backwards. The stock crossover is a series topology so I have no way to know the crossover point. But I assume it is around 1200 Hz. I assume the crossover should stop the BMS, or any other compression driver from going to low. But I really don't know how they work.

I guess I am thinking of trying something different, as I assume different drivers voice different. It seems to me regular drivers all have their sonic signature based upon material, magnets, baskets, wire etc. Why wouldn't a compression driver have a voice of its own? I am looking for something that has a more accurate level of playback. I have noticed of recent my classical is beautiful. Yet the strings and horns seem to overshadow instruments such as Harpsicord. When I use my headphones, I notice more details and subtle instrument textures. Could be my room. Anyhow, I wondered what a "higher quality???" Compression driver might bring.

I hear about cable and crossover changes all the time. Not so much drivers. I like what I have going on, but I'm always curious about change. Its a place I have not been.
 

Solypsa

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Change of driver could be fun.

On a more basic note have you ever pulled a driver to see how close the horn throat matches the driver exit? Maybe a little file work to 'port match' ;)
 
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Kingrex

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Change of driver could be fun.

On a more basic note have you ever pulled a driver to see how close the horn throat matches the driver exit? Maybe a little file work to 'port match' ;)
Yes I have. Its a precise fit. I believe the horn is machined by a cnc.

Thinking the spec of the new horn, it is going to throw off my crossover values. It could be hard to dial back in.
 
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Mark Seaton

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Yes I have. Its a precise fit. I believe the horn is machined by a cnc.

Thinking the spec of the new horn, it is going to throw off my crossover values. It could be hard to dial back in.

Unfortunately you can't just make dramatic driver changes and expect the passive crossover to work well, especially when you need to add another crossover for the BMS driver. From the examples I've seen, the PAP crossovers are rather idealist/purist/minimalistic in approach, and not overly concerned with flat power or frequency response. You are likely to gain more with someone skilled going through the crossover with real measurements than the random and unknown change of flavor you will see from swapping drivers. Of course that's very much a custom/DIY effort as compared to changing the type of crossover component.
 

morricab

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Apr 25, 2014
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I have been wondering about modifying my speakers. Specifically, changing out the horn driver from a Beyma to a BMS. Attached is a link to the BMS.

Overview (bmsspeakers.com)

It look like a great driver to me. I have already done all sorts of crossover component modifications. What I have not done is pull the crossover components off the board and hard wire them. I hear that is another great gain.

Anyhow, has anyone tried changing the driver and to what effect did it have.

Thanks
Rex
I don’t BMS an upgrade over Beyma necessarily . If they used one better Beyma drivers it is every bit as good. I have the Beyma CP-755Ti and this is a really great sounding driver mated to an 18 Sound XT1464 horn. I also love the sound of my Beyma CP350TI drivers in Iwata 600 horns. I prefer both to my Radian pb475Be drivers in the same Iwata horns. Could be the Radisns are not ideal in the Iwatas but I don’t have other horns to try for now.
 
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Kingrex

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morricab

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I think mine is a CD14ND. But not 100% sure.

Ah then you should upgrade to the CP755Nd driver...much better driver (I use the Fe version that is a much bigger driver overall...the Nd is more compact but otherwise the same). Then it is probably a drop in replacement for what you have (although you would need about 2db more attenuation) with regard to the crossover points.
 

Robh3606

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Yes I have. Its a precise fit. I believe the horn is machined by a cnc.

Thinking the spec of the new horn, it is going to throw off my crossover values. It could be hard to dial back in.


Hello Kingrex

Mark Seaton is giving you very good advice.

Rob :)
 
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