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What happens to frequencies less than rated range?


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5 minutes ago, garyrc said:

 

Get an AV (home theater) receiver (they are sometimes called AVRs) and cross over from sub to main at 80 Hz.  Then you can relax. 

Since you tend toward being a bass-head, run your 15 inch sub few dB "hot," and consider putting it very near a corner.  Your new receiver should be about 100 watts per channel; I assume the HSU has its own good amp built in to it.  Which HSU (a good brand) are you getting?

Hello sir, I ordered the VTF-15H MK2, it is supposed to be their flagship model and has variable tuning. A real fun sub from what I have heard.

 

I think I might take you up on the advice to swap it for an AVR. You telling me to do that from a woofer damage perspective, distortion based, or what? I am not worried about power as they are so sensitive my receiver has plenty to power them even if the woofers are working hard as well. 

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4 hours ago, psykoticboss said:

Hello sir, I ordered the VTF-15H MK2, it is supposed to be their flagship model and has variable tuning. A real fun sub from what I have heard.

 

I think I might take you up on the advice to swap it for an AVR. You telling me to do that from a woofer damage perspective, distortion based, or what? I am not worried about power as they are so sensitive my receiver has plenty to power them even if the woofers are working hard as well. 

 

The sub looks great!

My view is based on both minimizing potential woofer damage (they are damaged by over-excursion as well as over heating voice coil), and on minimizing frequency modulation distortion (as long as the woofers are pumping in and out more than about 1/16" we would expect sidebands -- spurious frequencies added on to the music, sometimes discordant, usually degrading some clarity.   Several speaker manufacturers try to ignore FM distortion, if their speakers pump too much, but it's there!

 

Here is an illustration of what can happen:

figure 2

 when two single tones are inputted to the same pumping loudspeaker cone.   Part of the reason for the modulation is the mid and higher tones having to ride back and forth on a pumping cone, sliding its pitch up and down, producing Doppler Distortion, as in the famed Doppler effect of a train whistle approaching, then passing into the distance.  In the upper graph we see the two tones that are inputted.  In the lower graph we see the sidebands, as well, the false sounds that are generated by too great a cone excursion.  In the case of your RP 600Ms, in which the woofer crosses over to the tweeter at 1,500 Hz (I think), something like this could happen if the two tones were 35 Hz and 900 Hz.  If your Klipsch woofers were cut off (actually rolled off) at 80 Hz by an AVR, the sound could be appreciably clearer.  In real music, there are many more original tones than two;  there could be a very large number of sidebands.  Now, how about the subIt will pump!  But, if it is rolled off at 80 Hz, there will be only a relatively minor frequency band for the pumping to form sidebands with, and they will be where the ear is a lot less discerning than it would be up where your Kilpsches are at work.  So, keep the deep bass out of the Klipsches!

 

Just for ducks, here is a kick drum.  As you can see, the two potentially loudest, potentially deepest on pitch,  and potentially longest lasting zones are below 80 Hz.  They should go through your sub and be mostly attenuated through your Klipsches.image.png.99828a83642f374004275b513bf8d267.png

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10 hours ago, garyrc said:

 

The sub looks great!

My view is based on both minimizing potential woofer damage (they are damaged by over-excursion as well as over heating voice coil), and on minimizing frequency modulation distortion (as long as the woofers are pumping in and out more than about 1/16" we would expect sidebands -- spurious frequencies added on to the music, sometimes discordant, usually degrading some clarity.   Several speaker manufacturers try to ignore FM distortion, if their speakers pump too much, but it's there!

 

Here is an illustration of what can happen:

figure 2

 when two single tones are inputted to the same pumping loudspeaker cone.   Part of the reason for the modulation is the mid and higher tones having to ride back and forth on a pumping cone, sliding its pitch up and down, producing Doppler Distortion, as in the famed Doppler effect of a train whistle approaching, then passing into the distance.  In the upper graph we see the two tones that are inputted.  In the lower graph we see the sidebands, as well, the false sounds that are generated by too great a cone excursion.  In the case of your RP 600Ms, in which the woofer crosses over to the tweeter at 1,500 Hz (I think), something like this could happen if the two tones were 35 Hz and 900 Hz.  If your Klipsch woofers were cut off (actually rolled off) at 80 Hz by an AVR, the sound could be appreciably clearer.  In real music, there are many more original tones than two;  there could be a very large number of sidebands.  Now, how about the subIt will pump!  But, if it is rolled off at 80 Hz, there will be only a relatively minor frequency band for the pumping to form sidebands with, and they will be where the ear is a lot less discerning than it would be up where your Kilpsches are at work.  So, keep the deep bass out of the Klipsches!

 

Just for ducks, here is a kick drum.  As you can see, the two potentially loudest, potentially deepest on pitch,  and potentially longest lasting zones are below 80 Hz.  They should go through your sub and be mostly attenuated through your Klipsches.

Thank you very much sir for writing all this out. Very educational. That makes perfect sense that distortion would be introduced when the woofer is trying to play sounds on opposite side of its spectrum like 50 and 900. Unfortunately I threw away the box to my receiver but I am going to touch base with Crutchfield and see if I might be able to swap it out with a home theater one.

 

Although, I finally got to really crank the 600s today and they (to my ear) sound pretty solid even playing pretty loud bass tunes with them. Not sure if I am not hearing the distortion or if I have not reached that volume level yet. One thing I was considering is this receiver can only produce 85 watts per channel. The 600s are rated for 100 watts of continuous power and 400 at the peaks. Will this Yamaha S-501 even get close to closing in on the headroom of the 600s? I only have the dial turned about 20% and they are pretty dang loud. Would that mean they are only getting 15-20 watts? If I am way farther from damage than I think I am, I might have more than enough room without risking damage. Another reason I would really like a home receiver is so I can get that LFE sub channel for movies in 5.1 and make the most use out of the sub. 

 

Anyways as you can tell I have been back and forth. Thank you for helping me understand the possibilities and what is going on behind the grill. Cheers. 

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15 hours ago, garyrc said:

 

The sub looks great!

My view is based on both minimizing potential woofer damage (they are damaged by over-excursion as well as over heating voice coil), and on minimizing frequency modulation distortion (as long as the woofers are pumping in and out more than about 1/16" we would expect sidebands -- spurious frequencies added on to the music, sometimes discordant, usually degrading some clarity.   Several speaker manufacturers try to ignore FM distortion, if their speakers pump too much, but it's there!

 

Here is an illustration of what can happen:

 

 when two single tones are inputted to the same pumping loudspeaker cone.   Part of the reason for the modulation is the mid and higher tones having to ride back and forth on a pumping cone, sliding its pitch up and down, producing Doppler Distortion, as in the famed Doppler effect of a train whistle approaching, then passing into the distance.  In the upper graph we see the two tones that are inputted.  In the lower graph we see the sidebands, as well, the false sounds that are generated by too great a cone excursion.  In the case of your RP 600Ms, in which the woofer crosses over to the tweeter at 1,500 Hz (I think), something like this could happen if the two tones were 35 Hz and 900 Hz.  If your Klipsch woofers were cut off (actually rolled off) at 80 Hz by an AVR, the sound could be appreciably clearer.  In real music, there are many more original tones than two;  there could be a very large number of sidebands.  Now, how about the subIt will pump!  But, if it is rolled off at 80 Hz, there will be only a relatively minor frequency band for the pumping to form sidebands with, and they will be where the ear is a lot less discerning than it would be up where your Kilpsches are at work.  So, keep the deep bass out of the Klipsches!

 

Just for ducks, here is a kick drum.  As you can see, the two potentially loudest, potentially deepest on pitch,  and potentially longest lasting zones are below 80 Hz.  They should go through your sub and be mostly attenuated through your Klipsches.

Hey I had a question hopefully you might know. My receiver has a 'bass control' knob that the manual says it can 'increase or decrease the low frequency response. Control range : -10db to +10 db.'

 

When I adjust this knob I hear the bass go down quite a bit. The Klipsch advisor said maybe I could turn down this knob, then overcompensate by turning up the sub gain. Would this work well? From what I can tell the 600s would still be getting full range, but the low frequencies(I am not sure up to what hz range) would be lower volume to the mains, which theoretically could help mitigate the potential damage/distortion..what do you think? I think thats the best bass management I would get without sending back. I called today and would have to pay a $60 restock fee since I threw away the box. 

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