New DIY Mid High (90deg) - AKA PM90

Re: New DIY Mid High

Ernie Montalvo said:
Very nice setup....no reservations about using top components!

Are the BMS drivers in the same cost bracket as the 18 Sound NSD4015? The only price I found for it(18 Sound) was €600 on their official price list.

Curious how they would compare but I imagine differences at this level would be minimal. Interesting battle of compromises between domes and rings.
Click to expand...


The 4594HE is a little more expensive but nowhere near as expensive as the Beryllium version of the 4015.

The problem with the NSD4015N is finding a suitable horn. It has a 1.5” exit and there are very few horns available with this throat size.

For this project the horn needs to have a cut off frequency down around 400Hz and not be too big to fit in the box, however I think the NSD4015N would be an excellent option and have the output needed.

I have directly compared the 4594 to the smaller 3” diaphragm version of the NSD4015N, the NSD1480N and preferred the 4594. If the NSD4015N sounds like its little brother I don’t think the VHF would sound as sweet as the BMS driver.

The other driver that looks interesting is RCFs new ND950; they are more like €330, and have a 1.4” throat. I believe RCF uses these in these the new TT5a’s in combination with HF950 horn which I have used.

I have some of the new TT2a’s which uses the same horn but the smaller ND850 compression driver. The TT2a is a fantastic little box, very natural voicing, but it sounds now where near as nice as this DIY. It’s also the same weight and has much less output, but it is a full range powered box.

Its difficult for me being located in Australia, I have to import all the components - BMS from the USA, horns from France and the 12s from England. If you are after any BMS drivers I would check out Assistance Audio, Jack has been fantastic to deal with.
 
Last edited:
Re: New DIY Mid High

Hey Peter,

Do you have the plans for the box drawn up yet? I have some ideas for flying hardware I'd like to sketch up and show to a Professor of Mechanical Engineering here at Penn State University. I think this idea could be built fairly easily, but I'm still trying to find off-the-shelf sources for some of the pieces. Possibly using my Penn State sources, I could have one tested to destruction and generate some meaningful load ratings. With those numbers and tests, a certification should be within reach.

Assuming they are flown one under the other, what do you think the splay angle should be?

One other question, the back side of the 12"s are vented into the horn mouth. What calculations are required to get the size and placement of that port correct?

Once again, great work.

Cheers,
Simon
 
Re: New DIY Mid High

Simon Coffin said:
Hey Peter,

Do you have the plans for the box drawn up yet? I have some ideas for flying hardware I'd like to sketch up and show to a Professor of Mechanical Engineering here at Penn State University. I think this idea could be built fairly easily, but I'm still trying to find off-the-shelf sources for some of the pieces. Possibly using my Penn State sources, I could have one tested to destruction and generate some meaningful load ratings. With those numbers and tests, a certification should be within reach.

Assuming they are flown one under the other, what do you think the splay angle should be?

One other question, the back side of the 12"s are vented into the horn mouth. What calculations are required to get the size and placement of that port correct?

Once again, great work.

Cheers,
Simon
Click to expand...

No I have not drawn any plans up yet – I will have to do some crude sketches as I don’t have any suitable software at the moment. The idea was to build a couple of prototypes and see how useful they are and if they sound any good … it’s looking good so far. After that maybe build another pair and document everything.

Fly-ware is technically fairly simple and straight forward, but I’m not sure how far I should go with publishing this information on a DIY forum.

My initial plan was just two strips of "rated" aircraft seating tack on the top of box with aluminum reinforcing to connect the top to the sides http://www.penn-elcom.com/default.asp?PN=R1438 . Penn can provide test certificates if needed. The strength calculations for this are trivial. I’m not sure what various countries require in terms of testing. Some may even require the whole box to be tested to a proof load / factor of safety of 10:1 … don’t know.

Having said that I would love to see your fly-ware idea.

In terms of splay angle; that will depend on the horn that you use. I’m going to order some 18sound XT1464 horns. Eighteen Sound say in their documentation that "Thanks to its compact vertical mouth dimensions, the XT1464 can easily be staked vertically when lower frequency control is required". So I suspect this maybe a good choice. The other DIY forums certainly like the XT1464 / BMS4594 as a combination.

I am also going to try some B&C 12NDL76 drivers as an option (they arrived yesterday) and I have a proprietary horn flare that a friend designed that looks excellent. Unfortunately the new horn will require the box to be redesigned.

With regard to the location of porting, this can be modeled in Hornresp including its position relative to the mouth, it’s not that critical but this design seem to work best with the port near the mouth of the horn. I actually considered cutting handles in the side of the box and also have them perform as the port. Handle holes would have been about the correct size.

One of the things I wanted to achieve was to have no wasted space inside the box. Every piece of timber should perform a critical function. That way the weight and volume of the box would be minimized.



Cheers
Peter
 
Last edited:
Re: New DIY Mid High

Marjan,

In Europe Hi-Q trap boxes are still very common, you are right. I mentioned Seeburg and TW Audio already. HK Audio, DB Audio and Dynacord also come to mind. The American market has largely abandoned the trap box configuration and adopted small format line arrays as the next step up from speaker-on-sticks. Unfortunately, the infrastructure needs of line arrays; lifts, trussing, amplification, cabling etc. are not for the faint of heart. Whereas in Europe, since size and weight play a larger role in purchases, everything is smaller and more expensive there, trap boxes that fit the need are still built and sold in quantity.

I think Peter has hit on a great concept for a powerful, light and compact speaker that fits neatly into the product void. We'll see how it performs and is ultimately accepted in the wild. I would be really interested in putting it up against a Danley or Fulcrum. That would be a David and Goliath moment...

Ciao
Simon
 
Re: New DIY Mid High

Simon said:
I think Peter has hit on a great concept for a powerful, light and compact speaker that fits neatly into the product void. We'll see how it performs and is ultimately accepted in the wild. I would be really interested in putting it up against a Danley or Fulcrum. That would be a David and Goliath moment...

Ciao
Simon
Click to expand...

Can't really get much better if any for the size and form factor. The only Fulcrum that can compete is an install product and Danley's are larger as well.

The other diy top that looks really interesting is Art Welter's SynTrip. Compact synergy with removable flare and good output with minimal weight.

Edit: Peter really makes me want to shell out a couple grand on some BMS with this project lol.
 
Re: New DIY Mid High

Hi,

I really hate to spoil the party, but is anyone aware of the costs involved in the system Peter showed us.

If you have two PLM10000 or even better PLM12K44 collecting dust as a door stop, I would say go for the project, but otherwise...

Yes, Peter mentioned the passive crossover for the 4594, but why didn't he go for that solution?
So much cheaper and less effort to get the processing right.
Maybe it would be difficult to create such perfect impulse response with the passive crossover?

It is my understanding, that with IIR ( passive ) filters you can do either an impulse alignment or phase alignment ( old debate ), so either IR looks ugly ( and believe me or not, it could look really ugly ), or you don't get perfect summation at crossover.

This will be a different speaker.

Another thing, that worries me: this driver ( 4594HE ) is still not listed on the BMS HP, is it an OEM product? These are usually sold in quantities unless the distributor has some leftovers.

And if you go for the perfect solution ( 4-way PLM per side ) and you have this customer, which is used to pay premium for this wonderfull Meyer Sound stack.
Do you really going to tell him: Next time I'll bring my New DIY Mid High together with my No Compromise Double18" Sub at the same rate.

And to close my little rant :)~:)~:smile: :
Peter's box is Not a high Q speaker, it has dispersion of 90x50 degree

Nethertheless a wonderfull project

Uwe

P.S. because the XT1464 has similar mouth size like the 950, I expect, that the 1464 will loose directivity control higher up than the 950
 
Re: New DIY Mid High

Uwe Riemer said:
Hi,

I really hate to spoil the party, but is anyone aware of the costs involved in the system Peter showed us.

If you have two PLM10000 or even better PLM12K44 collecting dust as a door stop, I would say go for the project, but otherwise...

Yes, Peter mentioned the passive crossover for the 4594, but why didn't he go for that solution?
So much cheaper and less effort to get the processing right.
Maybe it would be difficult to create such perfect impulse response with the passive crossover?

It is my understanding, that with IIR ( passive ) filters you can do either an impulse alignment or phase alignment ( old debate ), so either IR looks ugly ( and believe me or not, it could look really ugly ), or you don't get perfect summation at crossover.

This will be a different speaker.

Another thing, that worries me: this driver ( 4594HE ) is still not listed on the BMS HP, is it an OEM product? These are usually sold in quantities unless the distributor has some leftovers.

And if you go for the perfect solution ( 4-way PLM per side ) and you have this customer, which is used to pay premium for this wonderfull Meyer Sound stack.
Do you really going to tell him: Next time I'll bring my New DIY Mid High together with my No Compromise Double18" Sub at the same rate.

And to close my little rant :)~:)~:smile: :
Peter's box is Not a high Q speaker, it has dispersion of 90x50 degree

Nethertheless a wonderfull project

Uwe

P.S. because the XT1464 has similar mouth size like the 950, I expect, that the 1464 will loose directivity control higher up than the 950
Click to expand...

Hi Uwe,

In my case the costs – 2 x Lake LM26, 3 x Powersoft K6’s and 1 x Powersoft K10 :roll: … anyway I think it could be reduced to 1 x normal IIR 3 way stereo digital crossover and 3 amplifiers. The costs will be a "normal" looking phase response and maybe a little less SPL.

There are a few reason why this box was initially 3- way, Lake processed and is using the HE version of the 4594 other than I did have the amps and processing sitting around in a road case.

Firstly I wanted to build a "no compromise" design, the ultimate speaker on a stick. I wanted as much sound quality and SPL that I could possibly get out of a box that was small and light enough to be mounted on a standard heavy duty speaker stand. As I only envisaged that this would be a stand-alone box I selected a 90 degree horn, but there is no reason why a 60 degree version could not be built.

The 4594HE sounds great but also provides a lot of other advantages. You automatically have a point source for a large portion of the audio spectrum and it’s lighter and smaller than a separate MID + HF driver combination.

As I understand (I may be wrong) the HE version is a new addition to the range, but the standard 4594 will work just fine. I don’t see any problem using BMS’s passive crossover. I use this combination in my double 10 and horn. I suspect that I can probably get a bit more SPL running all active before I have any reliability issues. I note that USSpeakers now has the HE version of the 4599 mid driver for sale.

The other reason for the all active design, as I said above is that I already had amp racks with Lake processing set up to run my Flex Array, just had to plug the DIY in and write a new program. It’s also easier to use FIR filters and crossovers to achieve what you want compared designing passive crossovers.

As I said at the beginning of this threat, this is only a prototype. Next I’m planning to try some all IIR settings and see how well it performs. I have ordered some 18sound XT1464 60 degree horns to try, but it will take 2 or 3 weeks for them to arrive. I have some B&C 12’ drivers (12NDL76) that are a little lighter than the RCF and should work. They will provide a little more space inside the box and allow the XT1460’s to used - yes the clearances are that tight.

My initial impression is that it sounds better than the "Meyer stack". The advantage the DIY has is the amount of labour needed to set it up, the size truck you need to deliver it and SPL and coverage you can achieve without have to go to a fully flown line array. That’s mean a lot less expense for the customer, BUT it’s not on anyone’s rider :cry:.
 
Re: New DIY Mid High

I will admit that DIY isn't the most logical route for fully fledged sound professionals or even most weekend warriors, but when you want the best and have the skills to pull it off it can be one road there.

One can have all the amps needed and FIR correction for under $2,500. With a little labor on your own schedule you can have a world class box that will be unbeatable in its size class. Sound quality will equal systems costing thousands over.

These kind of endeavors are most suited for those that truly enjoy the process and personal payoff from building something with capabilities that would command top dollar in professional circles. If you rely on name brand gear to make a living that's a different situation altogether.
 
Re: New DIY Mid High

Ernie Montalvo said:
One can have all the amps needed and FIR correction for under $2,500. With a little labor on your own schedule you can have a world class box that will be unbeatable in its size class. Sound quality will equal systems costing thousands over.

These kind of endeavors are most suited for those that truly enjoy the process and personal payoff from building something with capabilities that would command top dollar in professional circles. If you rely on name brand gear to make a living that's a different situation altogether.
Click to expand...

Hey Ernie,

There will always be a tension between DIY projects and the business requirements of Rider acceptance. If the name on the box is important, then DIY is not an option, but for a lot of smaller companies, it is viable. In my area there are many smaller festivals and shows that rely on the reputation and pricing of the provider, rather than the brand names used.

That being said, I'm really curious how you get amps and FIR correction for under $2500.

Ciao
Simon
 
Re: New DIY Mid High

Simon Coffin said:
Hey Ernie,

There will always be a tension between DIY projects and the business requirements of Rider acceptance. If the name on the box is important, then DIY is not an option, but for a lot of smaller companies, it is viable. In my area there are many smaller festivals and shows that rely on the reputation and pricing of the provider, rather than the brand names used.

That being said, I'm really curious how you get amps and FIR correction for under $2500.

Ciao
Simon
Click to expand...


Simon,

I don't know how people feel about used amps but my experience has been great. There are plenty of late model touring class amps that can be had for relatively little money. Same with loudspeaker management systems. Run a standard IIR lms unit and use a minidsp drc in front of it to deliver FIR phase/amplitude correction. Depending on the models used, a full digital path can be had from the mixer to the output of the lms unit.

Ex: QSCPL340 $800, QSC PLX/PL $400+, Small tweeter amp $100-400, LMS $300+, Minidsp DRC $300

It's not as fun as having shiny new gear but you'll get fantastic results nonetheless. The only thing you won't get are brickwall filters. Should be obvious now that I'm a bottom feeder/hobbyist lol. I spend money on drivers and time on boxes. I bought used but good condition crests and crowns years ago for dirt cheap with a new DCX. Been through many outdoor summer gatherings and turned on almost daily. I fully expected to run into problems years ago with the age/perceived quality of the gear. Maybe I've been lucky I don't know.

Also keep in mind that FIR will not make a break a system with solid engineering behind it. For anyone interested in the audibility of flat phase download rephase, and foobar 2000 with convolution plug-in. You may be surprised how little or no difference you hear with most material.
 
Re: New DIY Mid High

Peter Morris said:
.....As I said at the beginning of this threat, this is only a prototype. Next I’m planning to try some all IIR settings and see how well it performs.....
.
Click to expand...
Hi everyone,

Tried a couple of IIR settings, here are the results of one of them.

They sound great, just as nice as the FIR but not as real. The difference is minimal but the stereo image does not have quite the same depth and realism.

I used all normal filters (no Lake raised cosine, no all-pass) except for an asymmetrical crossover to the VHF in an attempt to get better summation and phase response, but a standard 24dB crossover would work.
 

Attachments

  • dbl12IIR700.jpg
    dbl12IIR700.jpg
    266.8 KB · Views: 91
Last edited:
Re: New DIY Mid High

Peter Morris said:
Tried a couple of IIR settings, here are the results of one of them.

They sound great, just as nice as the FIR but not as real. The difference is minimal but the stereo image does not have quite the same depth and realism.

I used all normal filters (no Lake raised cosine, no all-pass) except for an asymmetrical crossover to the VHF in an attempt to get better summation and phase response, but a standard 24dB crossover would work.
Click to expand...

90% of the battle is a good box design and good components. I am glad the era of, 'We can fix that with DSP', has finally come to an end.
 
Re: New DIY Mid High

Mark DeArman said:
90% of the battle is a good box design and good components. I am glad the era of, 'We can fix that with DSP', has finally come to an end.
Click to expand...
A good test for the "we can fix that with DSP" guys is to move the mic around to different places in the coverage area and see if the response is the same---------------

If you have to "readjust"-then they have to figure out how to make it good for ALL the listeners-not just a single seat.

It is always best to fix physical problems with physical solutions.

The better a loudspeaker works physically, then the less "correction" it is going to need electrically.
 
Re: New DIY Mid High

Marjan Milosevic said:
I guess it is all about the taste of the people locally, and in general in Europe, but i would have set it up to slowly rise, rather then decline as the freq goes up.
Click to expand...
I prefer to have the speaker as flat as possible.

That way the engineer has a "clean canvas" upon which he can "paint" any sonic picture he wants, without the speaker system coloring the sound.

If this is for strictly music playback-then that can be a different story.

The joke is that if you ask a typical American about what they would add to a "typical" speaker system to make it better, and the answer would be a sub.

If you talk to an Asian, they will say to add a super tweeter.

It really depends on "what you are after".

Me-I want a speaker system to reproduce the incoming signal as accurately as possible without adding any of "its own sound".

But that may be just me (and a few others).

Of course as Tom Danley puts it "now that we have started to come close to the white canvas-people are starting to paint with feces"
 
Top Bottom