What can I say? 190Hz crossover, RS100 flush mounted, all modeled using the Edge by Tolvan for smoothest baffle contribution and drivers leveled using test tones and a RatShack analog sound meter which is very accurate in the crossover region. Behringer CX3400 crossover in 2-way mode. I only own a jigsaw, so that was the only power tool used in the build. All edges with a large round over by chisel, file and sandpaper as is the cutout for the RS100. The screws you see in the front will be painted black. It's quite an impressive sound to say the least, and I am very pleased though it doesn't get to blistering SPLs comfortably. All for under $200. Measurements to come... well in a few weeks anyways.
Dan
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
Dan
An externally hosted image should be here but it was not working when we last tested it.
So this is my first freq response graph. Taken in room at seating position and w/o smoothing. Can anyone tell me what I'm looking at in detail?
Thanks,
Dan
What do you want to know? It looks like it goes down to 60 hz and it looks like the woofer is running about 6 db hotter than the tweeter.
Is that a measurement of the ob from the first post? That's not what I'd expect it to look like with minimum filtering... What kind of filters are you using?
Is that a measurement of the ob from the first post? That's not what I'd expect it to look like with minimum filtering... What kind of filters are you using?
Hi Dan, wow, beautiful. And with hand tools, that's awesome. Mids look a little peaky to me (1k to 2.5k) but it could sound great in-room. How does it sound?
Thanks for the reply!
Mostly what I want to know is are there any problem areas other than the woofer being 6-10dbs too loud? I fix that in the second graph at the bottom of this post. The woofer level is now set as low as I can make it. I can still turn up the FRer if desired.
Just a Guy, what would you expect the response to look like? The filter is 24db/octave and I think it's LR. Not sure if that's considered simple or not.
What's up with the approx 70Hz dip that turns into a 140Hz dip in the next graph? The mic position is about half the distance of the original at very close to the same height.
Does it look like there's a resonance in the treble? Seems the response has a regular and repeating dip/hump cycle in stereo, but not as severe when just measuring one speaker. Am I getting some sort of comb filtering or does this graph look pretty good and I'm just worried about nothing?
Yes, this for the OB above.
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Here's my next graph I just took after playing with the crossover: one speaker only at about 4ft away with the mic pointed roughly between the woofer and tweeter. The treble looks a little smoother, but it still has dips and peaks but they seem tighter together and also theres now a boost at 15k.
Do you see any response issues I should be concerned with?
Thanks again,
Dan
Mostly what I want to know is are there any problem areas other than the woofer being 6-10dbs too loud? I fix that in the second graph at the bottom of this post. The woofer level is now set as low as I can make it. I can still turn up the FRer if desired.
Just a Guy, what would you expect the response to look like? The filter is 24db/octave and I think it's LR. Not sure if that's considered simple or not.
What's up with the approx 70Hz dip that turns into a 140Hz dip in the next graph? The mic position is about half the distance of the original at very close to the same height.
Does it look like there's a resonance in the treble? Seems the response has a regular and repeating dip/hump cycle in stereo, but not as severe when just measuring one speaker. Am I getting some sort of comb filtering or does this graph look pretty good and I'm just worried about nothing?
Yes, this for the OB above.
________________________________________________________________
Here's my next graph I just took after playing with the crossover: one speaker only at about 4ft away with the mic pointed roughly between the woofer and tweeter. The treble looks a little smoother, but it still has dips and peaks but they seem tighter together and also theres now a boost at 15k.
Do you see any response issues I should be concerned with?
Thanks again,
Dan
Oh, another thing that just struck me. That ratshack meter isn't trustworthy at all. It's supposed to be good in the crossover region, but it doesn't seem to be with a calibrated mic and soundcard.
Thanks RJBond3rd! It sounds incredible to me, but I built it. I wonder how much of that raggedness has to do with the whole OB thing?
I'd like to compare my graphs with unsmoothed ones by reputable manufacturers to see how I stack up. As far as measuring and modeling go, during the design phase all I had was free stuff from the web. Some of that jaggedness may also come from the highway right by my house. I can hear it well in my living room.
Dan
Thanks RJBond3rd! It sounds incredible to me, but I built it. I wonder how much of that raggedness has to do with the whole OB thing?
I'd like to compare my graphs with unsmoothed ones by reputable manufacturers to see how I stack up. As far as measuring and modeling go, during the design phase all I had was free stuff from the web. Some of that jaggedness may also come from the highway right by my house. I can hear it well in my living room.
Dan
Hi Dan, speaking strictly as a newb, I think the raggedness is just the in-room ringing of the sweep. In other words, at 1kHz, a bit of 999Hz is still ringing so you get some cancellation. I don't think the response is really /that/ ragged. If you took discrete measurements at certain intervals, I think (but cannot say for sure) that you'd end up with something that looks closer to a smoothed graph.
You have to measure it either outside or nearfield gated if you want to compare it to anything else. For an in room measurement it looks pretty good.
I would have expected a more rolled off bottom end and I suspect you might have had to use a fairly steep correction.
I'd say turn up the tweeter level a bit, keep the volume knob at a reasonable level, and you are done - if you want to be.
I would have expected a more rolled off bottom end and I suspect you might have had to use a fairly steep correction.
I'd say turn up the tweeter level a bit, keep the volume knob at a reasonable level, and you are done - if you want to be.
No correction at all on the bass. Just running them as is.
I don't know how to do the gated thing yet. First 10min with the program. All I know is it sounds good and the measurements look OK as far as I know.
I kind of want to get Dr. Geddes to rip these things apart. I want to know more of what are my warts. I just don't know enough about what I'm looking at.
Thanks for all the help so far!
Dan
I don't know how to do the gated thing yet. First 10min with the program. All I know is it sounds good and the measurements look OK as far as I know.
I kind of want to get Dr. Geddes to rip these things apart. I want to know more of what are my warts. I just don't know enough about what I'm looking at.
Thanks for all the help so far!
Dan
Those dips - are they audible?
Try reversing polarity of the tweeters - the dips may be cancellation caused by incorrect phase between drivers... Could also be comb filtering.
Try reversing polarity of the tweeters - the dips may be cancellation caused by incorrect phase between drivers... Could also be comb filtering.
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