60 Degree DIY Mid Hi - AKA PM60

Re: 60 Degree DIY Mid Hi

Almost all venues like this are a nightmare, interestingly enough last night there was no EQ used on FOH and the engineer said it sounded like a concert in a large arena.

BTW I would have loved to have an opportunity to drop by and say Hi to Bennett ... and Jack Arnott from Assistance Audio.

Tell us more about the new (?) 21 he had on display.
 
Last edited:
Re: 60 Degree DIY Mid Hi

Art Welter said:
Congrats, Peter!

Have you done any distortion testing to see how clean the DIY actually is?
I'm especially interested in the HD of the mid driver around 700 Hz compared to the cone drivers- the manufacturer's HD charts at 1 watt (on a different horn than you are using) don't tell a lot about rock and roll levels!

Art
Click to expand...

Hi Art - No I have not done any distortion measurements, but I can tell you they go loud and clear without any harshness you so often get … no ice pick in the forehead.

How are you going with your Keystones (?) … I modelled them the other day and they look great.

Thanks,
 
Last edited:
Re: 60 Degree DIY Mid Hi

Raimonds Skuruls said:
Hi Peter,
But what about to run a non linear distortion analysis of TDA software at SPL of 90, 100, 105, 110 dB?
Click to expand...

I could do that ... its just a matter of finding time. Too many boxes to built and subs to test.

What I want to do is have a look at the processing around 100Hz as a priority. Im not convinced I have optimized its time behaviour yet below 200Hz.

BTW loving your TDA EQ.
 
Re: 60 Degree DIY Mid Hi

Peter Morris said:
I could do that ... its just a matter of finding time. Too many boxes to built and subs to test.

What I want to do is have a look at the processing around 100Hz as a priority. Im not convinced I have optimized its time behaviour yet below 200Hz.

BTW loving your TDA EQ.
Click to expand...
Thanks Peter! What about to post some pre-post images of TDA EQ process here?
 
Re: 60 Degree DIY Mid Hi

Peter Morris said:
Trust :roll:- I’m reasonably well know in my part of the world and have had quite a bit of success especially with my subs over the years … my subs (design) have be used for large concerts (up to 20,000) and by many international acts, probably the most well know (especially for high SPL bass) was the Prodigy.

I’m also known for my work in developing the FIR settingsfor Turbo’s Sound Flex Array and my input into EAW KF750 horn resonance issues and some of the Gunness Focus settings.
Click to expand...

Awesome! Looks like this box isn't the only succes you've had and I probably used your presets in the past.
 
Re: 60 Degree DIY Mid Hi

Peter Morris said:
Hi Art - No I have not done any distortion measurements, but I can tell you they go loud and clear without any harshness you so often get … no ice pick in the forehead.

How are you going with your Keystones (?) … I modelled them the other day and they look great.

Thanks,
Click to expand...
I sold the entire Keystone/Paraline system to Daniel Biggerstaff in Colorado December of 2014. He has given good reports back, and has increased his business considerably.
Been using a pair of too-small 2x15" PPSL under the SynTripP cabinets for the few shows done in the last year. Definitely miss the clean LF output of the Keystones, but have been pleased with the SynTripP cabinets. Not quite the output of your DIY, but half the weight, and uniform 40 x 90 constant directivity (mostly ;^) pattern control from 400 to 16kHz.

Art
 
Re: 60 Degree DIY Mid Hi

Did anyone get a chance to look at B&C's new offering @ the DE1090tn. Not trying to stray away from the original components but if there are other options I would gladly like to see and know what they are and how feasible..
 
Re: 60 Degree DIY Mid Hi

The B&C doesn't seem to go low enough at the desired SPL. At 700Hz the B&C has 3dB less output on paper, in combination with the recommeded crossover of 800Hz I don't think its a good fit for this box unless you compromise on output.
 
Re: 60 Degree DIY Mid Hi

Jelmer de Jong said:
The B&C doesn't seem to go low enough at the desired SPL. At 700Hz the B&C has 3dB less output on paper, in combination with the recommeded crossover of 800Hz I don't think its a good fit for this box unless you compromise on output.
Click to expand...

That's exactly what I would expect. The new B&C looks fantastic but may not be happy going down as low as need at full power. The BMS is designed to operate as low as 300Hz with a peak power handling of 1000w above 500Hz. To keep the size down the double 12" mid horn was bent / folded. That made it long enough to go down to 80Hz - 100Hz when ported; because of this and the directivity caused by the two dipole mid horn mouths the HF driver/ horn needs to get down to 600Hz - 700Hz.
 
Last edited:
Re: 60 Degree DIY Mid Hi

Hi Peter, thx for your reply in the FIR thread re the minidsp unit.
I'm thinking it's more appropriate to continue asking about it here, particularly since i'm wanting to try to use it to tune the DIY.

Do you think it makes sense to begin by individually tuning each section of the DIY for smooth response and flat phase within each section's intended bandwidth?
I'm thinking if phase response can be kept flat on each section in its pass-band, and also kept flat out of band to maybe where response is down 12db or so, but response is still summing.....
Well .... it seems all you would then need to do when combining the sections is adjust for relative levels and delays ...

I've found an inexpensive 8 channel unbal to bal converter that has 20db boost capability, to get past the 2v and interface issues. And I can just keep using the PLD amp limiters...

As you can see, I'm trying to talk myself into this budget FIR experiment ! The Lake, Xilicas, BSS, Four Audio, etc are so dang expensive and simply seem very under-powered vs the opendrc...

As far as IIR, I've had very good luck learning smaart and playing with assymmetrical types, orders, out of band eq, etc. The meyer webinars on filters are great. The DIY makes such a good learning platform for this.. (Biggest problem as usual is good testing environment...)

Results are really great, very enjoyable....and now the FIR bug is biting !
 
Re: 60 Degree DIY Mid Hi

Mark Wilkinson said:
Hi Peter, thx for your reply in the FIR thread re the minidsp unit.
I'm thinking it's more appropriate to continue asking about it here, particularly since i'm wanting to try to use it to tune the DIY.

Do you think it makes sense to begin by individually tuning each section of the DIY for smooth response and flat phase within each section's intended bandwidth?
I'm thinking if phase response can be kept flat on each section in its pass-band, and also kept flat out of band to maybe where response is down 12db or so, but response is still summing.....
Well .... it seems all you would then need to do when combining the sections is adjust for relative levels and delays ...

I've found an inexpensive 8 channel unbal to bal converter that has 20db boost capability, to get past the 2v and interface issues. And I can just keep using the PLD amp limiters...

As you can see, I'm trying to talk myself into this budget FIR experiment ! The Lake, Xilicas, BSS, Four Audio, etc are so dang expensive and simply seem very under-powered vs the opendrc...

As far as IIR, I've had very good luck learning smaart and playing with assymmetrical types, orders, out of band eq, etc. The meyer webinars on filters are great. The DIY makes such a good learning platform for this.. (Biggest problem as usual is good testing environment...)

Results are really great, very enjoyable....and now the FIR bug is biting !
Click to expand...

This is more or less what I have done with the Lake – make the amplitude and phase flat (within reason) within each band. When you add everything together with linear phase crossovers they add perfectly and there will be no issues in the time domain.

To minimize the system's latency I have used an IIR filter between the subs and low.

In my latest settings I have EQ-ed the natural roll-off of the DIY to perfectly match a 12dB - 100Hz Butterworth function (to about -10dBor more). Then I add 12dB Butterworth high-pass filter to create an almost perfect 24dB LR curve (Two 12dB Butterworth filters added together = 24dB LR)

I then used a 24 dB LR crossover on the subs and an all-passfilter so that the phase response of the sub matched the DIY from between (about) 50Hz to 200Hz.
 
Re: 60 Degree DIY Mid Hi

Mark Wilkinson said:
(Biggest problem as usual is good testing environment...)
Click to expand...

Any cheap forklifts in your area? Most forklifts usually do over 4 meters, even if it was a lower lift one you could build it up with pallets etc. Forklifts are an item when brought at the right price, you should easily get your money back on a few years down the track. Not sure what your physical surroundings and space freedoms are though..... Here in NZ I would usually be able to get a rough one for 2 grand(after keeping an eye on the market for a few months), not too much when considering you can pretty much get that money back when your done and when you’ve already spent so much on the project. Obviously most people don't have the space for this luxury. A little outside the box thinking........
 
Top Bottom