[cujobob]

What kind of output are you guys with a single dual woofer OB servo sub getting in your rooms?

[TRADERXFAN]

I thought I read a slightly differently worded post from you on having bottoming issues with this.  You should email Brian at rythmik. He helped me with mine. Not sure what you are experiencing. I had felt my gain was too low for the output my integrated gave me, and he increased it with a new board. I am sure he can help you diagnose your problem.

Output for me is full, but bass is something I hear and not so much feel.  Although I am considering adding a 2nd sub pair to see how that enhances things.

-Tony

[Danny Richie]

I am using them as the lower section for the upper P-Audio coaxial driver. So those two SW-12-16FR's are easily keeping up with a 97db efficient speaker. And that is with the gain control on the amp only turned up to about a 1 to 2 o'clock position.

[cujobob]

Well I am running 95 db speakers and the sub is bottoming out with playback levels in the low-mid 80s....I edited my post because I wanted to try it with my new receiver that's coming before saying more.

Thanks for the info.

[Danny Richie]

Two SW-12-16FR's might not be enough for you if you are expecting them to keep up with a pair of 95db efficient speakers. You may need to add another pair.

I can't see you bottoming them out to reach playback levels in the low to mid 80's though. They will do that with only a single watt of power.

[longdrive55]

Hi Danny,

I've wondered about this too. I was considering the Venue build, but I really want to build an OB speaker with VERY high efficiency. I've got the mids and tweeters that will run at about 103db/1watt (actually a little higher by manufacturer specs, but I figured I'd need to attenuate to help the subs keep up).

I was going to run a stereo pair of subs and amps (total 4 speakers, 2 amps). Will this keep up? If not, would 6 speakers, 2 amps keep up?

Finally, are there any measurements published on your OB subs yet? My mids are flat to 300hz and approx 2db down at 200hz. Still trying to figure out if I'll need to augment with a midbass solution.

Thanks

[Danny Richie]

I was going to run a stereo pair of subs and amps (total 4 speakers, 2 amps). Will this keep up? If not, would 6 speakers, 2 amps keep up?

You might consider 3 woofers per amp. That will give you some cushion.

Finally, are there any measurements published on your OB subs yet? My mids are flat to 300hz and approx 2db down at 200hz. Still trying to figure out if I'll need to augment with a midbass solution.

My measurements show no issue with crossing at 200Hz and with the crossover section all the way up they will actually reach a crossing point near 300Hz.

[cujobob]

Hmmm.....I hooked up my sub to my new receiver and it's still not giving me much output and is clipping at very reasonable SPL.  I'm talking 78-80 db and still clipping at times.  Is there something that could be wired wrong?  I had this all built for me so not sure what to check.

[zybar]

Hmmm.....I hooked up my sub to my new receiver and it's still not giving me much output and is clipping at very reasonable SPL.  I'm talking 78-80 db and still clipping at times.  Is there something that could be wired wrong?  I had this all built for me so not sure what to check.

I seem to recall somebody else having this problem and it turned out to be wired incorrectly.  I would check the wiring.

I will soon have a pair of sub with two drivers per "cabinet" and the person I bought them from assured me I will be quite impressed with their SPL output and the quality of the bass.

George

[Danny Richie]

I set mine back up last week and accidentally plugged the sensing coil into the output of the amp and the voice coil into the sensing system.

It still played and it wasn't noticeable on low level music or something with little bass, but when I really cranked it up, the bass wasn't there. I finally realized what I did.

[TRADERXFAN]

Also, I learned that if the servo connection to the driver is loose then you can get some wierd problems. Double check that its tightly attached to the terminals.

[cujobob]

Hmmm...my sub has speakon connectors from the amp to the sub...and all the wiring is prefitted and glued down in place...I'm unable to try swapping driver and servo connections for these reasons.  What would happen if the polarities were swapped?  I can easily try that but won't risk it if it can harm
anything.

[Danny Richie]

It is not as likely that the polarities are swapped as the wiring is swapped onto the wrong coils. If so then you can just flip the wiring to the voice coils so that they are connected properly. Follow the wiring to see if it is correct.

[cujobob]

It is not as likely that the polarities are swapped as the wiring is swapped onto the wrong coils. If so then you can just flip the wiring to the voice coils so that they are connected properly. Follow the wiring to see if it is correct.

hmm it seems as though the polarity was swapped.... Things are better, have to do some testing...

[dvenardos]

 
This is going to be my next project to go into the queue.

[cujobob]

It's a very nice sounding sub, but keeping it away from walls is actually kind of tough in a normal room.  Now that I have this working properly, I'm actually surprised by the output.  I actually had to turn the gain down from the 12 o'clock position

[corndog71]

I noticed with my sealed servo sub that it took several hours of playing music through it for it to loosen up.  I've had to lower the gain a couple of times. 

It's pretty awesome now!

[zybar]

It's a very nice sounding sub, but keeping it away from walls is actually kind of tough in a normal room.  Now that I have this working properly, I'm actually surprised by the output.  I actually had to turn the gain down from the 12 o'clock position

Excellent!!

How far away from the wall do you have the sub?

I can have mine anywhere from 3-8' with no problem.

George