60 Degree DIY Mid Hi - AKA PM60

Re: 60 Degree DIY Mid Hi

Evan and I did have a ton of fun a few Saturdays ago when we did the mini-shootout. It was nice to hear the DIY with a sub as well as in comparison to other speakers. For the first cabinet I've ever built, it didn't turn out half bad, though certainly not perfect. As far as it not being as "compact" as Evan was hoping, that is certainly my fault - mine is a tad taller than the other boxes so I could have an easily removable horn baffle, and I didn't angle the back sides of the box like Peter did. I haven't weighed it yet, but I'd say I came in right around 80 lbs. Certainly manageable.

Evan is pretty spot on with the listening test results. The M4 kicks ass, the 960 is stupid loud, and the DIY was a little cleaner. I will say that the coaxial driver really makes a difference, especially active rather than passive. Evan and I didn't mess with it much at all, and it still sounded absolutely fantastic. When I have some extra time, I'll be able to clean up the DIY settings a bit more, since Evan and I left a lot to be done.

As far as Evan's subs go, I'll spill the beans: It's a big box with a big driver and a big port. Additionally, it also has a big amp! :cool: Really - Evan's done a great job with them. In all honesty, if my limiters weren't set so low (think at least 3dB, if not more), we might have been able to outrun his sub, as the 12s had plenty left in them. Even so (if I know Evan) by the time I catch up his subs will be even louder, so what's the point?

The definitive conclusion from that day was that the DIY is a great box that makes a lot of sound and sounds good doing it. I can't wait to revise my CNC design in the coming weeks and get the thing sounding as good as it gets without FIR processing. Might even take a pass at it with the TDA if I get excited - who knows?!

Max, your box looks great.. nice first build ! This has been my second DIY attempt; first was labhorns back in 2003. They still work really well...I'm sold on DIY and how much you learn. Don't think I've saved a dime, but sure l have learned a lot.

FWIW, I've noticed as I get better at tuning, using smaart and other tools, the DIY60 gets clearer and clearer throughout the spectrum. It seem very sensitive to subtle IIR eq, more so than I'm used to with self powered boxes. My acid test on tuning is my girlfriends dog, and how often it barks cause it think it hears something real sounding that it can't place! Dog's been barking a lot lately :)

If you do get into FIR, the minidsp route, using the free rephase software to generate filters, is dang cheap IMO, and the instructions on how to do it on the minidsp site are easy to follow.
The only real penalty so far has been fussing with interfacing consumer to pro.
Smaart can make the files rephase needs. I'm going through driver by driver tuning right now...need some warm weather to get outside and do the DIY mid section....

Also, if I may repeat Marjan's question... what kind of power were you and Evan putting on your box? And what kind of limiting?

Another FWIW, using a PLD 4.5 with two channels paralleled for mid (2250w), and a channnel each for the two coax drivers, I get 130-132 db with blinking ever few seconds on the amps -10db lights on mid, every 5-10 seconds -10db blinking on HF, and almost never on VHF.
So there's clearly more MID room left, which is the constraint. I'm using 60Vrms limiting on MID, and won't see limiting light up until I can get back outside....had to look up the color of limit lights in the manual to know what to look for haha

Good luck! Mark
 
Re: 60 Degree DIY Mid Hi

To answer both Mark and Marjan's question: I powered it with crappy shit not worth discussing on these noble forums.

*cough* Behringer DCX and iNuke because it's the crap I could find and afford *cough*\
 
Re: 60 Degree DIY Mid Hi

lol the DCX is actually not a bad unit..

I agree, not a bad unit at all. Doesn't sound as good as the x-32 family stuff, but is definitely more capable in x-over function. Biggest problem for use with the DIY IMO, is low filter count.
Got a 4 channel i-nuke, and it works fine too. Not sure about how much single channel wattage it has driving higher impedance, but other than that and the the hair dryer fans ... (which the QSC PLD also has :( .... IMO, it works well
 
Re: 60 Degree DIY Mid Hi

Here's some impedance plots of the DIY 60, in case they help... taken with DATS....
16 ohm 4594 HE, RCF 12's

Passive x-over
DIY #1 passive 60.JPG


4594HE HF
DIY #1 HF 60.JPG

4594HE VHF
DIY #1 VHF 60.JPG

RCF 12's
DIY #1 MID.JPG
 
Re: 60 Degree DIY Mid Hi

To answer both Mark and Marjan's question: I powered it with crappy shit not worth discussing on these noble forums.

*cough* Behringer DCX and iNuke because it's the crap I could find and afford *cough*\

And here I was gonna hang my head in shame at attempting to power one of Michael's wedges with an iNuke. Now I don't feel so bad, thanks Max! :twisted:
 
Re: 60 Degree DIY Mid Hi

Hi Peter,

Hey, do you have any impulse plots of the 4594 on the 60 degree handy? Each section separately, as well as together?
I'm getting a real clean looking HF plot, but kinda hairy looking VHF....

Thx !
 
Re: 60 Degree DIY Mid Hi

Hi Peter,

Hey, do you have any impulse plots of the 4594 on the 60 degree handy? Each section separately, as well as together?
I'm getting a real clean looking HF plot, but kinda hairy looking VHF....

Thx !

I don't have them separately. Are you using the passive crossover on the 4594? If you are that will make the impulse response look like an ordinary speaker.


Here is a plot of the 60 degree using the lake. The phase of the all bands has been modified / flattened with some all-pass filters to get perfect alignment etc.
 

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Re: 60 Degree DIY Mid Hi

I don't have them separately. Are you using the passive crossover on the 4594? If you are that will make the impulse response look like an ordinary speaker.


Here is a plot of the 60 degree using the lake. The phase of the all bands has been modified / flattened with some all-pass filters to get perfect alignment etc.

Thanks Peter, I'm not using the passive crossover. I'm experimenting with minidsp hardware and rePhase FIR generating software..

It's been too windy for many days here to measure the whole box outside, so I've been trying to tune the coax indoors. Maybe looking at impulse of each coax section doesn't make sense?

This morning there was a lull in the wind, and I managed to get a quick measurement outside....damn it is so windy again...
Here's a whole box impulse. Can you see things to address with impulse?

impulse1r.jpg



Here's transfer as well.
This represents the first try on the mid section with minidsp...I can see work needs to be done with EQ, and the timing looks a little off between mid and coax.
But on the whole I'm happy as heck with tuning progress and sound.

transfer1r.jpg
 
Re: 60 Degree DIY Mid Hi

Thanks Peter, I'm not using the passive crossover. I'm experimenting with minidsp hardware and rePhase FIR generating software..

It's been too windy for many days here to measure the whole box outside, so I've been trying to tune the coax indoors. Maybe looking at impulse of each coax section doesn't make sense?

This morning there was a lull in the wind, and I managed to get a quick measurement outside....damn it is so windy again...
Here's a whole box impulse. Can you see things to address with impulse?

View attachment 14346



Here's transfer as well.
This represents the first try on the mid section with minidsp...I can see work needs to be done with EQ, and the timing looks a little off between mid and coax.
But on the whole I'm happy as heck with tuning progress and sound.

View attachment 14347

Looks really good Mark!
 
Re: 60 Degree DIY Mid Hi

I don't have them separately. Are you using the passive crossover on the 4594? If you are that will make the impulse response look like an ordinary speaker.


Here is a plot of the 60 degree using the lake. The phase of the all bands has been modified / flattened with some all-pass filters to get perfect alignment etc.

Don't forget that the microphone will have some impulse response issues. I also glued some rubber on the 60 degree horn to make sure it was dead and had no resonant issues.

http://www.earthworksaudio.com/measurement/
 

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Re: 60 Degree DIY Mid Hi

How much of a difference does the rubber make, you think? Is that just rubber flooring that you've chopped up?

How much difference does the rubber make … Hmmm next question.
To be serious, I’m not sure, I was chasing down some of issues and I changed a couple of things ... everything got better, adding the rubber was one of the things I did.
From past experience hard plastic horns often have resonant problems. I have measured the resonance with accelerometers, this time I just stuck some cheap 3mm rubber on the horn … it was just much easier to do that than try and measure it … I think the impulse response looked slightly better.
I suspect you many not notice any change by doing this, but if you find and correct 10 little insignificant problems, you will hear the difference.
 
Re: 60 Degree DIY Mid Hi

Hi guys,

Been following this thread for some time and I think a couple of friends here in the UK are convinced to build four of these boxes, maybe more! Only question is around the SketchUp or CAD plan, or even final drawings as I can't seem to find them in thread and my carpenter friend hasn't had a response to his PM asking for a copy.

Any ideas? I'm also likely to translate the settings into a Powersoft K/X series preset which I would be happy to share once finished.


Sent from my iPhone
 
Re: 60 Degree DIY Mid Hi

Hi guys,

Been following this thread for some time and I think a couple of friends here in the UK are convinced to build four of these boxes, maybe more! Only question is around the SketchUp or CAD plan, or even final drawings as I can't seem to find them in thread and my carpenter friend hasn't had a response to his PM asking for a copy.

Any ideas? I'm also likely to translate the settings into a Powersoft K/X series preset which I would be happy to share once finished.


Sent from my iPhone

Kyle, send me a PM with your email and I'll send you some plans.
 
Re: 60 Degree DIY Mid Hi

Update on rePhase / minidsp DIY60 tuning....

Finally had a chance to see what latest settings look like outdoors...
DIY2 6144a r.JPG

This is no sub and a 48db LR at 100hz.

Here's same DIY settings indoors, but on top a JTR OS sub using 48 db linear-phase LR @100hz (and @28 for HP.)
Low end on DIY has something to tie phase to....

inside2 full apr9 r.jpg

Current goal is to see how low in freq I can get flat phase. Then to back off, and optimize phase flatness versus latency...

Really, really, pleased with the sound !!!!

While I was set up to test, I checked out a UPA-1P and a JTR 3TX
For grins...here they are...

UPA-1p
UPA1 out r.jpg


3TX no HP filter
JTR2 out r.jpg
 

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Re: 60 Degree DIY Mid Hi

Excellent Mark! What sort of latency numbers are you seeing while processing the subs as well?

Hi Don, the latency is about 75ms.
But this is an overkill first run at, ...... 'see what can be done at the limit of the processor'.
I mean I'm using maximum taps, and reaching into steepest x-over topology....

So there is a lot of room to cut back latency. I think alot.....and without changing phase or amplitude curves much.
At this point, getting a feel for the cutbacks available, I'm guessing optimal sound quality vs latency, lies in the 25 -30 ms range.
I'm thinking this gets phase flat on the mids down to 80hz, and subs from 80 up... IOW near perfect summation and flat phase from 80hz up...while needing to let natural sub delay below 80 be what it may be...

Only more testing will tell...
Maybe 25-30 ms is still too much for live work?
That will be a shame...cause if the sound quality at 25-30ms stays like what I've got now...damn, we want it.
I've simply never heard recorded music like this. Never heard so much definition at all frequencies, particularly in the sub-to-main transition region.
I always knew the DIY had outstanding transient response...never knew it could go all the way down to the sub, with the same clarity and balls...just my lack of tuning ability really...rePhase rocks.

Hey Peter, thanks again for sharing such a great design.
And Don, thank you for your invaluable contributions as well.
Mark be a happy camper ... He have most excellent sound and be learning tons :)