60 Degree DIY Mid Hi - AKA PM60

[Max Warasila]

Re: 60 Degree DIY Mid Hi

Helge,
Both Mark and Peter modified the 90 deg box to fit the 60 deg horn (I believe). If I can get a sketch of the modifications they made I'd be happy to update the CAD file and post it.

I built 2 of the 60 deg versions as posted earlier in this thread but had to modify some parts as I built and the cut-off corners ended up being a PITA during the construction. If I had to do it over again I would go with no angled corners.

Considering that so far I've been planning to go off your drawings, this is good to know. :?~:-?~:???: The biggest change is probably going to be the routed inset for the 12s rather than the spacer.

 

[Peter Morris]

Re: 60 Degree DIY Mid Hi

Just to be difficult I cut the back corners off the latest version - I makes the box look smaller and much less DIY

 

[Don J Davis]

Re: 60 Degree DIY Mid Hi

Just to be difficult I cut the back corners off the latest version - I makes the box look smaller and much less DIY

Peter, Did you use the 90 deg plans and make it deeper or wider? Some of the guys want to build the box and I'd like to give them the latest version of the drawings.

 

[Don J Davis]

Re: 60 Degree DIY Mid Hi

Considering that so far I've been planning to go off your drawings, this is good to know. :?~:-?~:???: The biggest change is probably going to be the routed inset for the 12s rather than the spacer.

The 60 deg plans will work as drawn but there is one part that is not usable but it's a part that can be eliminated, part D. There is no physical way to install it. So by making the 12" baffles a little longer you don't need the part. I hate to see guys pay for CNC and have an unusable part.

 

[Peter Morris]

Re: 60 Degree DIY Mid Hi

Peter, Did you use the 90 deg plans and make it deeper or wider? Some of the guys want to build the box and I'd like to give them the latest version of the drawings.

I used the 60 degree plans with the following changes.

- I didn't use the 10mm spacer to mount the 12" drivers
- the front baffle is set back 30mm instead of 15mm. My plan was to cut 15mm of the box so the it would be 440 deep instead of 455, but I think I will leave it.
- I have cut the back corners of the box to make it look smaller and less DIY - its a lot of work - FWIW I built the box square and then cut the corners off. I cut them at 40 degrees; that's all my saw would accommodate.
- I rounded the first bend of the horn a bit more, but I don't think it matters. See my pictures on this thread.

The box is 385mm x 455mm x 930mm - the 90 degree box was 385 x 430 x 930. The extra 25mm was to accommodate the deeper 60 degree horn. I saved 10mm by eliminating the space and reduce to clearance behind the compression driver by 5mm (10 + 5 = 15mm) hence the front baffle was moved back an additional 15mm.

 

[Mark Wilkinson]

Re: 60 Degree DIY Mid Hi

Helge,
Both Mark and Peter modified the 90 deg box to fit the 60 deg horn (I believe). If I can get a sketch of the modifications they made I'd be happy to update the CAD file and post it.

I built 2 of the 60 deg versions as posted earlier in this thread but had to modify some parts as I built and the cut-off corners ended up being a PITA during the construction. If I had to do it over again I would go with no angled corners.

Yes, I built mine off the 90 degree horn plans. It use the designs interior dimensions....the only thing REALLY different if the work I did to make the 90 and 60 degree horns&baffles interchangeable. This was alot of work with brass inserts, precisely located countersunk bolts, two layer baffle board for the XT1464, etc. I'll try to pass the details on if anybody cares.
I'm giving thought to how to build another pair of 60 deg without the interchangeable stuff and will compare notes with the group when and if I come up with something.

 

[Mark Wilkinson]

Re: 60 Degree DIY Mid Hi

I used the 60 degree plans with the following changes.

- I didn't use the 10mm spacer to mount the 12" drivers
- the front baffle is set back 30mm instead of 15mm. My plan was to cut 15mm of the box so the it would be 440 deep instead of 455, but I think I will leave it.
- I have cut the back corners of the box to make it look smaller and less DIY - its a lot of work - FWIW I built the box square and then cut the corners off. I cut them at 40 degrees; that's all my saw would accommodate.
- I rounded the first bend of the horn a bit more, but I don't think it matters. See my pictures on this thread.

The box is 385mm x 455mm x 930mm - the 90 degree box was 385 x 430 x 930. The extra 25mm was to accommodate the deeper 60 degree horn. I saved 10mm by eliminating the space and reduce to clearance behind the compression driver by 5mm (10 + 5 = 15mm) hence the front baffle was moved back an additional 15mm.

Your boxes look great!! What kind of saw did you use? How much of the corners could you cut? Brilliant way to do it !

 

[Peter Morris]

Re: 60 Degree DIY Mid Hi

I used a portable electric saw - It could not cut all the way through so I cut one side at 40 degrees and the other at 50 degrees. I will measure it tomorrow for you.

I'm really happy with the way the boxes look, so much so I'm thinking about cutting the corners of the 90 degree version ... just need to fabricate some nice grills for the 60's now.

Cutting the corners off is however a lot more work.

 

[Peter Morris]

Re: 60 Degree DIY Mid Hi

I used a portable electric saw - It could not cut all the way through so I cut one side at 40 degrees and the other at 50 degrees. I will measure it tomorrow for you.

I'm really happy with the way the boxes look, so much so I'm thinking about cutting the corners of the 90 degree version ... just need to fabricate some nice grills for the 60's now.

Cutting the corners off is however a lot more work.

I cut 80mm (back) x 95mm(side) off, then added a bit of 12mm ply over the corner. - it saves about 1kg.

 

[Mark Wilkinson]

Re: 60 Degree DIY Mid Hi

I cut 80mm (back) x 95mm(side) off, then added a bit of 12mm ply over the corner.

Thx Peter, that's more than i expected ! I'm going to explore your method as I ponder another pair of 60 degrees..

 

[Mark Wilkinson]

Re: 60 Degree DIY Mid Hi

All,

Though I shouldn't be, I am seriously considering building a single DIY mid-high, just so we have one in the DC area, and so I have something to do this summer (in addition to many things). If anything, I'm going to see if I can physically make the box itself - my carpentry skills are not extraordinary. I plan on building mine with maybe a 1/4" extra on the front for a full length grill, just because I like it more. ~:-D~:grin:

I went ahead and created an excel spreadsheet estimating the cost of the box itself, located here: https://www.dropbox.com/s/p6zaglzy0lsupyy/sf_pm_diymidhigh_priceestimate.xls?dl=0

Please let me know of any corrections to be made (as I've only have a rough idea as a project outsider here) and they will be reflected in the document. With any luck I hope to find myself with a finished box before the year is up!

Hi Max, been meaning to reply for some time...sorry for the delay. Spreadsheet looks fine, looks conservative. I guess what always ends up costing me more than expected, are the inevitable new tools "I really need to do this box" lol

The one thing you probably will want to keep a good eye on, is how the continuing plans for a 60 degree version unfold. It has been pretty clear that Peter, Don, and myself have been really trying to keep weight down for the speaker on a stick idea.
The width and depth of the XT1464 horn made it clear the weight of the original 90 degree version would be hard to match.....and I think how to incorporate the horn is kinda why no single plan emerged definitively.....just my thoughts here...
Anyway, the reason I say to keep an eye out, is if you want to get the XT1464 horn behind a grill, your interior width will have to be at least the width of the horn, in addition to the depth consideration you mentioned.

If you're not concerned with keeping the box on a diet, you'll have no problem ~:-D~:grin:

 

[Don J Davis]

Re: 60 Degree DIY Mid Hi

Box 1 is done, number 2 is ready for paint.

 

[Klaus Zimmermann]

Re: 60 Degree DIY Mid Hi

Box 1 is done, number 2 is ready for paint.

NICE :thumbup::thumbup::thumbup:

 

[Jason Joseph]

Re: 60 Degree DIY Mid Hi

Box 1 is done, number 2 is ready for paint.

Yeah thats looking good, quite lurker been keeping up with the updates..

 

[Jack Arnott]

Re: 60 Degree DIY Mid Hi

Hi Guys, I don't have anything to add to the limiter settings beyond what the calculator, and BMS's specs say.
A couple of thoughts on the subject.

1) I don't sell very many diaphragms, to my way of thinking. But I also don't know what some of the OEM manufacturers stock and sell.
2) The post about frying the HF diaphragms, I dont get that. I have not sold or loaned any drivers to that user. So there must be some kind of myth, or misconception on how the driver should be used.
2A) I sell almost the same amount of HF and MF diaphragms.
3) I would be interested in how the cabinets are doing in regards to the different bands, and limiter settings. EG, most of my designs are not very aggressive in regards to the HF/LF or Mid High/LF, such as pairing one 1" driver with a 12", or one coaxial compression driver with two dual 15" speakers. (Even my unity type box with two dual horn loaded 12", in a 40x20 horn, the mid/highs kind of loaf.) As such, I don't push my compression drivers very hard. Also, I use the passive crossovers with the coaxial compression drivers, so I have no experience with limiting on mid vs. high. I do like the sound of the coaxial as low as it can go (I use them to 300hz), but again, have no experience with biamping them. I would think that 500 hz should be a great place to cross them over, but would like feedback on how the different bands are in relation to each other. Peter, is the design working as you intended, as far as power/output per band? And how hard are you pushing your bands, in relation to the limiter settings, in the times you have used the boxes?

(Sorry to not respond for a bit. I had a couple of replies that were either wordier than this, or got eaten by reboots or crashes while I was thinking of other things.)

Regards, Jack Arnott
Assistance Audio

 

[Mark Wilkinson]

Re: 60 Degree DIY Mid Hi

Box 1 is done, number 2 is ready for paint.

Looks great Don, nice craftsmanship !

 

[Mark Wilkinson]

Re: 60 Degree DIY Mid Hi

I cut 80mm (back) x 95mm(side) off, then added a bit of 12mm ply over the corner. - it saves about 1kg.

Hi Peter, .......trying to picture things ......did the miter cut, cut into the 12" baffle boards? If not, did you need to have the little "bridge" piece between the baffle boards to keep the miter cut from reaching into the boards?

Switching gears....This weekend I kind of stepped back from playing solely with the DIYs, and set them up next to my other 2 rigs for comparison.
I wanted to see if my enthusiasm for the DIYs was the famous "it's the newest, so it has to sound the best" syndrome :lol:

I also wanted to see if all the spectacular detail from the DIYs was maybe due to an elevated HF...
The other 2 rigs were 3TX & orbit shifter subs, and meyer mts4a, a four-way active full range box. I used the DIY's with the OS subs.

Unfortunately, this was indoors. But at least it was in a fairly large room I'm familiar with.
I know subjective evals like this are fraught with peril....and often worthless but here goes anyway...
(No eq on any for comparison's sake, just a little coarse time alignment...)

The first thing I learned is that the detail in the DIYS is not due to a HF bias.
The mts4a is definitely the brightest box of the three rigs. It is a great sounding box that seems to do everything right from 30hz to as high as I can hear, but it simply doesn't have the transient response and midrange clarity of the DIY.
The 3TX was the warmest of the three, and had surprising transient detail given the softer voicing....I guess due to its BMS driver. It has a very nice tonal balance. They work really well with the crankin OS subs (as do the DIYs)
The DIY....easily the most open, alive, dynamic sounding box....easily. I can forget the 'new box is best syndrome' ~:-D~:grin:

 

[Don J Davis]

Re: 60 Degree DIY Mid Hi

The DIY....easily the most open, alive, dynamic sounding box....easily. I can forget the 'new box is best syndrome' ~:-D~:grin:

Glad to hear that Mark!

I plan on doing some AB comparisons when time permits. In my small world, all I have to compare them to is my SRX rig. The JBL's will get loud but tend to get kind of bright in the HF when pushed. Also, IMO they don't have the detail the DIY has.
I love the SRX stuff and won't part with it but I feel like I now another tool in the tool box.

I'm really looking forward to an outdoor gig where I can open them up and have ample subs to go along for the ride.

 

[Peter Morris]

Re: 60 Degree DIY Mid Hi

Hi Guys, I don't have anything to add to the limiter settings beyond what the calculator, and BMS's specs say.
A couple of thoughts on the subject.

1) I don't sell very many diaphragms, to my way of thinking. But I also don't know what some of the OEM manufacturers stock and sell.
2) The post about frying the HF diaphragms, I dont get that. I have not sold or loaned any drivers to that user. So there must be some kind of myth, or misconception on how the driver should be used.
2A) I sell almost the same amount of HF and MF diaphragms.
3) I would be interested in how the cabinets are doing in regards to the different bands, and limiter settings. EG, most of my designs are not very aggressive in regards to the HF/LF or Mid High/LF, such as pairing one 1" driver with a 12", or one coaxial compression driver with two dual 15" speakers. (Even my unity type box with two dual horn loaded 12", in a 40x20 horn, the mid/highs kind of loaf.) As such, I don't push my compression drivers very hard. Also, I use the passive crossovers with the coaxial compression drivers, so I have no experience with limiting on mid vs. high. I do like the sound of the coaxial as low as it can go (I use them to 300hz), but again, have no experience with biamping them. I would think that 500 hz should be a great place to cross them over, but would like feedback on how the different bands are in relation to each other. Peter, is the design working as you intended, as far as power/output per band? And how hard are you pushing your bands, in relation to the limiter settings, in the times you have used the boxes?

(Sorry to not respond for a bit. I had a couple of replies that were either wordier than this, or got eaten by reboots or crashes while I was thinking of other things.)

Regards, Jack Arnott
Assistance Audio

Hi Jack,

In terms of power output per band I think the design is working exactly as intended. I have had very few opportunities to push the box to see what it would do and where the limits are. General I have only had one double 18 under it and that’s not enough.

I have tried the 90 degree version with a 500Hz crossover. When you push it hard it seems happier at 600 – 700Hz. This is probably more to do with the cut off frequency of the horn rather than the compression driver. I think the 60 degree version will operate happily to 500Hz – 600Hz because the horn is bigger and has alower cut off frequency.

I posted a video of the amps in operation on the DIY with adouble 18 sub. https://youtu.be/3n2Bxbc-Ytw Note: the subs and DIY LF are 4 ohms and the HF & VHF are 16 ohms so the compression driver is getting comparatively 6 dB less power than the Sub and LF with the same amplifier meter reading.

Amp rack configuration:-

VHF – Top amp
HF
LO
SUB - Bottom Amp

The metering on the Powersoft K6 is a bit strange
· Red clip
· Amber – 1 dB
· Green -3dB
· Green –6dB
· Green -10dB
· Green – not sure, manual does not say … about-15dB
· Green -60 dB - signal present light.

 

[Peter Morris]

Re: 60 Degree DIY Mid Hi

Hi Peter, .......trying to picture things ......did the miter cut, cut into the 12" baffle boards? If not, did you need to have the little "bridge" piece between the baffle boards to keep the miter cut from reaching into the boards?

Switching gears....This weekend I kind of stepped back from playing solely with the DIYs, and set them up next to my other 2 rigs for comparison.
I wanted to see if my enthusiasm for the DIYs was the famous "it's the newest, so it has to sound the best" syndrome :lol:

I also wanted to see if all the spectacular detail from the DIYs was maybe due to an elevated HF...
The other 2 rigs were 3TX & orbit shifter subs, and meyer mts4a, a four-way active full range box. I used the DIY's with the OS subs.

Unfortunately, this was indoors. But at least it was in a fairly large room I'm familiar with.
I know subjective evals like this are fraught with peril....and often worthless but here goes anyway...
(No eq on any for comparison's sake, just a little coarse time alignment...)

The first thing I learned is that the detail in the DIYS is not due to a HF bias.
The mts4a is definitely the brightest box of the three rigs. It is a great sounding box that seems to do everything right from 30hz to as high as I can hear, but it simply doesn't have the transient response and midrange clarity of the DIY.
The 3TX was the warmest of the three, and had surprising transient detail given the softer voicing....I guess due to its BMS driver. It has a very nice tonal balance. They work really well with the crankin OS subs (as do the DIYs)
The DIY....easily the most open, alive, dynamic sounding box....easily. I can forget the 'new box is best syndrome' ~:-D~:grin:

Hi Mark,

Love your work J.

· You have compared this box with some serious highend competitors – I have not heard the JTR’s 3TX but I have heard great thing about them and read many positive comparisons with other boxes.
· You can obviously adjust you DSP settings to make the box as bright or warm as you want. The clarity you talk of is not a function of EQ but the component’s and basic box design. Every driver operates its piston range.
· I suspect you will refine your settings a little over time.
· The Lake FIR processing is up another step interms of sound quality.~~:smile:

I have been trying a few ideas for the front grills ... any suggestions to improve the appearance are most welcome ???