Integrating Force with full range speakers

DavidDG · « **on:** 7 Sep 2004, 06:45 pm »

Hi,

My current speakers are Meadowlark Audio Shearwater HOTROD speakers which use transmission line loading on the bass. The manufacturer said they are 3 dB down at 35Hz. I would concur that they go pretty low.

I am running these speakers with a Welborne Labs Apollo amp putting out about 15 watts per channel. The speakers mate well with these amps and I haven't noticed any clipping.

I am considering mating these speakers with a sub and trying to relieve the main channel amps of having to amplify the lowest frequencies, say around 40-50Hz and lower, by inserting a capacitor between the preamp and amp.

I would appreciate any feedack from someone who has done something similar using the Force sub and their impressions.

Thank You,

Mike Dzurko · « **Reply #1 on:** 8 Sep 2004, 07:30 pm »

David:

You're on the right track. A single quality cap used as a highpass is a very effective way to transition to a sub. Crossing over low as you plan to do makes getting the integration easier than a higher crossover point will. I don't know your speakers intimately, so I can't say for sure that 40 or 50Hz is optimum. The room also plays a major factor. For example; if your room had a peak at 60Hz, you could highpass above that, say 70-80Hz and bring in the sub below the peak. A way to "cheat" the room. I'd say start off at around 40-50 Hz and you can fine tune up or down depending on the room character.

DavidDG · « **Reply #2 on:** 8 Sep 2004, 11:37 pm »

Thanks for the response Mike.

I agree with the room interaction being a factor. I just figured the lower the crossover point the less of an issue there will be integrating a single sub with the main channels.

Thanks again,

Dave

Mike Dzurko · « **Reply #3 on:** 9 Sep 2004, 01:01 am »

Dave:

You're very correct. Most of the time, the lower the crossover frequency to the sub, the easier it is to get it to disappear. Working on the room response becomes a whole other issue, that can become that "icing on the cake" that really makes the system sing. I'd say start with a pretty low XC frequency and work from there. Most importantly, enjoy the music along the way!

Jay S · « **Reply #4 on:** 9 Sep 2004, 03:10 am »

My nOrh 9.0s have a rated -3dB of about 33 Hz. I am using the 35 Hz XO point on my Force sub. I set both XOs to 35 Hz, yielding a 4th order (24 db/octave) slope. I haven't played around too much but this seems to work pretty well.

DavidDG · « **Reply #5 on:** 9 Sep 2004, 04:34 am »

Hi Jay,

Do you run your Norh's full range?

Thanks,

Dave

Jay S · « **Reply #6 on:** 9 Sep 2004, 04:40 am »

Yes, I run the nOrh's full range. I could get them to roll off at a higher frequency if I plug the ports but I haven't tried that. I don't really want the Force to play to high in the frequency range since I don't want its sound to be locateable.

I'm not going to bother getting an active XO -- I don't think the cost and complexity are worth it. If nothing else, my long term goal is to simplify my system (electronics) and reduce the amount of $$ invested without making compromises in sound quality.

ieales · « **Reply #7 on:** 10 Sep 2004, 06:34 pm »

For my 2p, I'll take a slight blur in the bottom octave or two, rather than trash the other 8 or 9 octaves with extra crud in the signal path.

Since the signal to your mains will be going through the cap, it will be audible, no if's and's or but's. PLUS the wire and connectors will add their own sticky fingerprints. Ditto for active xovers. [The best xover I ever heard was the Bryston 10B.]

Be sure to use a HIGH QUALITY film cap if you decide to try a passive xover. If you like I can post links to a paper or two on cap sonics. Any cap small enough to fit in an RCA connector is probably not sonically optimum.

True bottom ocatave low end is enormously difficult to record. Most recording studios are too damped and / or too small to adequately allow a 20Hz funamental to develop. Many engineers roll the bottom as a matter of course to aleviate air conditioner rumble. Only a very few disks have gorgeous low end and I'm unwilling to risk the heart of the audible band for the feet.

DavidDG · « **Reply #8 on:** 10 Sep 2004, 10:36 pm »

I agree that each component has a sound.

The cost to experiment would be fairly low in the big scheme of things. The reason I would consider this method is to relieve as much demand from the main amps as possible.

I'll test and if it sounds bad, I'll remove the caps.

Thanks,

Dave

Mike Dzurko · « **Reply #9 on:** 13 Sep 2004, 08:27 pm »

Quote from: DavidDG

I agree that each component has a sound.

The cost to experiment would be fairly low in the big scheme of things. The reason I would consider this method is to relieve as much demand from the main amps as possible.

I'll test and if it sounds bad, I'll remove the caps.

Thanks,

Dave

Dave:

Once you've had time to experiment, please report back with your findings. Then everyone gains. Thanks!