Two doubts in my mind.
1. We use a calibrated mic to get a flat output from two drivers one is a woofer and the other is a CD. The Umik-1 says the SPL is the same on both. A lot of time and effort went into achieving this. But... the CD seems to over power the woofer when listening to music. I had to dial back the CD by about -6 DB on the SPL meter to make it sound right. Is this normal / desireable / or Im just an idiot who has made a basic mistake.
2. I have a full range 8 inch that when added to the 15 inch woofer and the CD sounds amazing. My only problem is the woofer is 300 watts the CD is 80 watts RMS. And the 8 inch I want to add is only rated to 20 watts. How do I safeguard my 8 inch driver should somebody crank the music up. I know adding a L pad or resistors would limit the power going to this driver. But it also reduces its output to a point where it can no longer be heard. Am I missing something. Or is the only solution to buy a 80 watt full range. ?.
1. We use a calibrated mic to get a flat output from two drivers one is a woofer and the other is a CD. The Umik-1 says the SPL is the same on both. A lot of time and effort went into achieving this. But... the CD seems to over power the woofer when listening to music. I had to dial back the CD by about -6 DB on the SPL meter to make it sound right. Is this normal / desireable / or Im just an idiot who has made a basic mistake.
2. I have a full range 8 inch that when added to the 15 inch woofer and the CD sounds amazing. My only problem is the woofer is 300 watts the CD is 80 watts RMS. And the 8 inch I want to add is only rated to 20 watts. How do I safeguard my 8 inch driver should somebody crank the music up. I know adding a L pad or resistors would limit the power going to this driver. But it also reduces its output to a point where it can no longer be heard. Am I missing something. Or is the only solution to buy a 80 watt full range. ?.
Your problem is not clear, CD is 80 watts RMS.
my advice dont listen indian music dont trust & dont buy indian local electronic item , maybe problem is indian music have recording gain high, studio guy low hearing problem bad recording quality,
Suggest test sony wb emi music album
buy japan usa china or europe sound system
my advice dont listen indian music dont trust & dont buy indian local electronic item , maybe problem is indian music have recording gain high, studio guy low hearing problem bad recording quality,
Suggest test sony wb emi music album
buy japan usa china or europe sound system
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Dear Chinoy,
The energy within typical audio splits equally around 300-350Hz. Also compression drivers are much more efficient than most woofers which is why the level matching is required.
Untreated concrete / plastered surfaces have an overall effect of raising the treble due to reverberation buildup. Applying a suitable house curve or room treatment would alleviate this issue to an extent. Ungated measurements are also rendered incorrect due to some of these effects.
The energy within typical audio splits equally around 300-350Hz. Also compression drivers are much more efficient than most woofers which is why the level matching is required.
Untreated concrete / plastered surfaces have an overall effect of raising the treble due to reverberation buildup. Applying a suitable house curve or room treatment would alleviate this issue to an extent. Ungated measurements are also rendered incorrect due to some of these effects.
Make the two most efficient speakers (db pr 2,xx volt or Watt pr. xx db) . Not the other way. Measure at crossover frequencies on all three. Yes- I guess you only need a db-app on your phone and play the 2 tones at moderate level. Dont measure lowest frequency on CD and dont measure highest frequency on bass driver.
It's hard to tell exactly how you are measuring things from your description, and knowing this is critical to giving useful feedback.
Measured how? In-room (including room gain)? Quasi-anechoic indoors (windows out room effects)? Measurement distance? Gating? Outdoors?
Are you just checking a spot frequency on each driver or are you looking at the entire frequency response?
The speaker should only measure flat outside raised high above the ground or in an anechoic chamber. In room it should measure closer to the Harman curve due to the off axis behaviour of the woofer compared to the the beaming compression driver / horn.
'Flat' in room hardly ever sounds right.
Rob.
'Flat' in room hardly ever sounds right.
Rob.
@SpeakerBob may have answered a question I had about using VituixCAD to flatten drivers using the transfer function block, G(f). I tried to use gated in room and ground plane measurements. Those both failed. Then I tried outdoor ground plane measurements. Those failed too. It didn't work right until I put the woofer 12 feet up (3.65 meters) and then merged the near field woofer response before using the Optimizer to flatten on axis. They sounded great after that.
I was hoping that wasn't necessary because it isn't easy for everyone to do that. But maybe matching to a room curve solves the problem.
I was hoping that wasn't necessary because it isn't easy for everyone to do that. But maybe matching to a room curve solves the problem.
I don't try to get a flat response, it doesn't always work that way.
The reason we want to know the response of the mic is so that we know what to expect from it, that's all. Consider Tenson's post #10. It outlines one example of the bigger picture.
It is hard to tell from this what your system looks like, and what measurements you've taken exactly.
Can you post your FR measurements of each driver individually, and the summed output of both with crossover in place? And details of the measurement conditions (distance, gating, etc) and the crossover? Forget the FR driver for now.