Midbass compliment to Othorns?

[Telescopic]

Hello everyone, first time posting here and I'd like to thank Ricci for the putting the Othorn plans out in the world. Living in Denver I have have been blessed to listen to the world renowned Basscouch Soundsytem (by Jeff Bailie) at The Black Box wich features 8 othorns and 4 Tannoy iq10/18b. Now the time has come to build ourselves a "small" but robust stereo stack for house/warehouse/renegade parties. Othorns are a no brainer for 27-80hz (already started on our first cab) and we are leaning towards the Peter Morris PM90's for our Mid/High down to 100hz leaving a hole from 80-100hz. I have been searching around for some midbass designs but apart from the HD15 from speakerplans im not too sure what to fill the gap with that can match the quality of our other choices. Is there any midbass designs that people have ran with Othorns and would recommend for a 1 box per side stack? If our goal is not sheer output from the PM90s could we get away with running the Othorns to 90hz and letting the PM90s take over from there slighlty lower than recomended?

I am at the beginning of my DIY/pro audio journey and any help would be much apreciated, thank you for your time. 

 

[peniku8]

Pretty sure you'll be fine with just the Othorns and the PM90s. @dsl1 uses them with two SKHorns and is pretty happy with them, so I've heard.

Also, I'd say 100Hz is more upper-bass than mid-bass. If crossing the Othorn at 80Hz or higher, remember to take care of the spike at 108Hz, but other than that, the combo should perform nicely over the crossover region.

[kipman725]

I also wouldn't bother with an additional mid bass cab initially as you will be adding quite a bit of cost and complexity to the system that will run without it, going from 4 amp/dsp channels per side to 5.  Saying that I am (slowly slowly) building a midbass horn for the 100-500Hz range which is an unfolded exponential horn so it might be worth looking at what I did: https://www.diyaudio.com/forums/pa-systems/349105-mega-midbass-straight-horn-139db.html

This horn was designed for outdoor usage

The paper you should read before designing a bass horn is "
11. "Low-Frequency Horn Design Using Thiele/Small Driver Parameters," Presented at the 57th Convention of the Audio Engineering Society, Preprint No. 1250 (K-7), (May 1977).
"

http://xlrtechs.com/dbkeele.com/papers.htm

The changes I would make to my horn in covering say 60 - 120 Hz would be to no longer bother having a smooth straight horn profile and instead folding the horn.  I would also reduce the mouth area  to less than half the ideal mouth area and use multiple boxes per side.  The HD15 has quite a short path length so if you can tolerate a larger box you can get much closer to true horn performance.

[SME]

17 hours ago, Telescopic said:

Hello everyone, first time posting here and I'd like to thank Ricci for the putting the Othorn plans out in the world. Living in Denver I have have been blessed to listen to the world renowned Basscouch Soundsytem (by Jeff Bailie) at The Black Box wich features 8 othorns and 4 Tannoy iq10/18b. Now the time has come to build ourselves a "small" but robust stereo stack for house/warehouse/renegade parties. Othorns are a no brainer for 27-80hz (already started on our first cab) and we are leaning towards the Peter Morris PM90's for our Mid/High down to 100hz leaving a hole from 80-100hz. I have been searching around for some midbass designs but apart from the HD15 from speakerplans im not too sure what to fill the gap with that can match the quality of our other choices. Is there any midbass designs that people have ran with Othorns and would recommend for a 1 box per side stack? If our goal is not sheer output from the PM90s could we get away with running the Othorns to 90hz and letting the PM90s take over from there slighlty lower than recomended?

I am at the beginning of my DIY/pro audio journey and any help would be much apreciated, thank you for your time. 

 

Hello also from Denver here! 

You started in on one of the Othorns already?  I'm not sure how far along you are, but you may want to consider the Skhorn or Skram instead.  They have much cleaner response to well above 100 Hz, and I think most people  here regard those two designs to largely obsolete the Othorn.  If you have a choice, I very strongly suggest you go with one of these newer BP6 designs.

If you already have Othorns you want to use, then I'd say the situation is a bit of a mixed bag.  The 80-100 Hz region is pretty narrow---essentially 4 semitones (or a major 3rd) apart.  However, crossovers are not an all-or-nothing thing but involve blending over a pretty wide range, even with e.g. 4th order slopes.  IMO, the Othorns will probably sound even better crossed even lower at like 60 Hz, at which point, a dedicated mid-bass section (for say 60-150 Hz) starts to make more sense.

Looking at Ricci's compression sweeps for the Othorn, I don't expect EQ applied above 100 Hz will be very help helpful because the response above 100 Hz actually changes a lot with the signal level at medium-to-high levels.  EQ which sounds good at low signal levels might actually make things worse at high signal levels.

[Ricci]

I'd echo SME here. The Othorn is still a very good sounding design but I'd consider the Skram instead. It's smaller, lighter, has flexible tuning options and is simpler to build. Output and SQ should be the same if not a bit better due to the more extended top end. Issues don't start till higher in frequency that the Othorn.  

[Mjhfowler]

On 9/8/2020 at 4:48 PM, Telescopic said:

 have been searching around for some midbass designs but apart from the HD15 from speakerplans im not too sure what to fill the gap with that can match the quality of our other choices. Is there any midbass designs that people have ran with Othorns and would recommend for a 1 box per side stack? If our goal is not sheer output from the PM90s could we get away with running the Othorns to 90hz and letting the PM90s take over from there slighlty lower than recomended?

I am at the beginning of my DIY/pro audio journey and any help would be much apreciated, thank you for your time. 

 

What did you end up going with in the end?

I've gotten excellent results crossing the ots at 70htz to the ES18-BPH running Fane 18XB drivers. They stack perfectly and let the ots work where they are comfortable and lifts a super punchy kick up to chest height nicely as well as getting your tops comfortably above a crowd.

[Professionally_Curious]

On 5/11/2022 at 11:54 AM, Mjhfowler said:

What did you end up going with in the end?

I am also interested in finding out!