I use an ev dh7 on a ev hr90 horn.
I have the "cd-eq" jumper connected on the active crossover.
I parallel a 1uf with 21ohms, both in parallel with the driver (more hf-boost).
All of this is crossed over actively at 750hz Linkwitz Riley 24db to a pair of Eminence Magnum 15lf in a jbl 4508a cab with 1 port stuffed (30hz tuning).
I've been debating trying one of the 400hz stereo lab round tractrix horns, but to me it would not load as low as the ev (lack of pattern control at a higher frequency, thusly less lower mids farfield).
What ya using ?
Norman
I have the "cd-eq" jumper connected on the active crossover.
I parallel a 1uf with 21ohms, both in parallel with the driver (more hf-boost).
All of this is crossed over actively at 750hz Linkwitz Riley 24db to a pair of Eminence Magnum 15lf in a jbl 4508a cab with 1 port stuffed (30hz tuning).
I've been debating trying one of the 400hz stereo lab round tractrix horns, but to me it would not load as low as the ev (lack of pattern control at a higher frequency, thusly less lower mids farfield).
What ya using ?
Norman
The top section is a P-Audio BM-D750 driver running from 700Hz on up with a P-Audio 4525 horn. The bass bin is a DIY dual bin with Emminence Kappalite 3015LF drivers. I recently picked up the bottom end from 50Hz on down with individual Klipsch RSW-15 subs. The active crossover is an Ashly Protea 4.8SP.
The DIY subs I am finishing will be used exclusively for the movie LFE channel.
The DIY subs I am finishing will be used exclusively for the movie LFE channel.
Thank you. I plan on doing that tomorrow morning. I decided to remove the drivers to lug those behemoths up a flight of stairs. Good thing too, they were heavy enough as it was.
I will post the results ASAP. I honestly don't know what I will be looking for in terms of good vs. poor results, so your help will be appreciated.
It depends on the driver... I don't think it will make a huge difference the electrical system will be the predominant force in the equation?... but as the suspension loosens up the Vas should go up and Fs down.
IOW, the tuning of the system will go down. set up a tone @ fs and drive your speakers @ or near xmax for 20-40 hrs while hanging them in the air naked.
I don't think at the efficencies we are talking about there will be actual audible changes, but it may measurable, and yes those peaks will shift downwards.
2 things:
1. yes breaking them in makes a HUGE difference on certain subs, the 3015lf being one of them.
2. Sine waves at the tuning frequency of the system (typically an excursion minimum) at xmax for 20-40 hours sounds like a recipe for a toasted voice coil. I typically break in my subs hung in free air (so they make minimum noise) and at no more than 10v. I've heard many people talk about varying frequency, etc... and I'm not sure if that is of value or not. However running them at a very low frequency (20-40hz) does have value. I like to use ethan's 1hz test tones and allow my mp3 player to repeat the 20-30hz and 30-40hz tones for break-in. I also use a 1 minute 'silence' track so that I don't have 100% duty cycle going to the coil. Without that, even though I haven't officially 'overheated' the coil, I seem to get voice coil 'goo' close to the port, so I know that can't be good. You can find ethan's test tones here: RealTraps - Test Tone CD
Power in @ Fs will be excursion limited... in no way can you toast the VC. The reason to choose Fs is you get the most motion and the least watts in.
http://www.gr-research.com/burnin.htm here's some driver designers weighing in, they seem to agree with me.
http://www.gr-research.com/burnin.htm here's some driver designers weighing in, they seem to agree with me.
I finally had some time to finish putting the subs together and was able to hook them up to a Behringer ep4000. I had to set the sensitivity on the amp to absolute minimum, or they are just too loud. Here is a shot of the location I chose for now and where they were for REW frequency sweep testing.
Attachments
I ran REW after hooking everything up to see what kind of room response I was getting. So far, so good. These things are shaking my room big time. The first graph is an uncorrected, non-Eq'd run. Not too bad considering the frequencies we are working with. Seems my bass traps are doing a decent job. The second graph is the result after a little EQ with my DCX2496. I still need to work on that nasty 90Hz dip.
Tomorrow, I will continue working on my room layout and then run Audyssey Pro to see how it sounds all together with a good movie. I will only be using these as LFE channel subs.
Tomorrow, I will continue working on my room layout and then run Audyssey Pro to see how it sounds all together with a good movie. I will only be using these as LFE channel subs.
Attachments
I would love to see a graph of the pair split up, like one in the front and the other in the back of the room. That might smooth out the 90hz dip.
Did you modify the plans at all or did you use the leaked plans? I'm very impressed with the extension you're getting.
How musical are these?
And sorry one last question. Is the back of your JC bass bins enclosed or open, like the klipschorns? That is another build I'd like to research but didn't find much with a few minutes of using google power.
Did you modify the plans at all or did you use the leaked plans? I'm very impressed with the extension you're getting.
How musical are these?
And sorry one last question. Is the back of your JC bass bins enclosed or open, like the klipschorns? That is another build I'd like to research but didn't find much with a few minutes of using google power.
The idea of putting both subs next to each other is to prevent cancellations and have them act as one. I beleive placing one up front and one in back would be a nightmare to setup.
With the few tests I ran, the LF is 'everywhere' and not localized.
The back of the DBBs are closed. It is a ported enclosure in the standard sense. You will not find the plans for those on the web as far as I know.
I don't plan on using the TH subs for music since I have the DBB's and dual Klipsch RSW-15s handling the bottom end. The TH subs are for LFE only. Using them for music would require you time align the TH subs with your mains. I'm measuring 22ms system delay on the subs, which is substantial when compared with my mains.
With the few tests I ran, the LF is 'everywhere' and not localized.
The back of the DBBs are closed. It is a ported enclosure in the standard sense. You will not find the plans for those on the web as far as I know.
I don't plan on using the TH subs for music since I have the DBB's and dual Klipsch RSW-15s handling the bottom end. The TH subs are for LFE only. Using them for music would require you time align the TH subs with your mains. I'm measuring 22ms system delay on the subs, which is substantial when compared with my mains.
The MiniDSP should have a firmware update soon (if not already) that could handle the delay. And provide significant EQ possibilities for the subs.
Having subs in different locations can actually benefit your setup by smoothing the response out. Earl Geddes recommends a minimum of three subs in different locations throughout the room. As does JBL. Actually I just tried to find the JBL white paper regarding this for you, but it looks like it's been removed. Or at least my link no longer works.
Having subs in different locations can actually benefit your setup by smoothing the response out. Earl Geddes recommends a minimum of three subs in different locations throughout the room. As does JBL. Actually I just tried to find the JBL white paper regarding this for you, but it looks like it's been removed. Or at least my link no longer works.
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.