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Will try, only went with 2db difference with the "good" sub and I stopped because it was loud enough.

Just tried, with the other sub I can go till -4 MV till the limiter kicks in (green light blinks), driver is not making any clunking sound.
So one sub can go 6 db louder with no clunking and the limiter kicking in.
On the "clunking" sub I have the clunking sound at -10db MV and green light is steady (no limiter).

I understand the importance of gain matching but all my previous subwoofers where in the same location with each exactly the same gain on the amp and when measuring with audessy they where always 0,5 dB close to each other. Subs are equal distance parallel to each other. Left and right wall about 2 meters from MLP.
gain matching is all about running out of headroom at the same time. If you have plenty of headroom to spare, then level matching especially when it sets the actual gain pretty close is more than good enough. I’m assuming there is little variance between the gain knobs on Rythmik subs and if you’re using the same model subs, then you should be able to eye ball it pretty easily to set the gains close. Anything fishy in the mini-DSP? Are all settings linked between the two subs?
 

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gain matching is all about running out of headroom at the same time. If you have plenty of headroom to spare, then level matching especially when it sets the actual gain pretty close is more than good enough. I’m assuming there is little variance between the gain knobs on Rythmik subs and if you’re using the same model subs, then you should be able to eye ball it pretty easily to set the gains close. Anything fishy in the mini-DSP? Are all settings linked between the two subs?
Just default configuration, no house curve or anything.
Just swapped the channels again and played every sub individually. Issue stays the same, not related to the channel.
 

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Just default configuration, no house curve or anything.
Just swapped the channels again and played every sub individually. Issue stays the same, not related to the channel.
well to me it sounds like a bad sub then. Audyssey EQ’s the subs together and applies the same EQ to them both, so it’s not like it’s going to be boosting one more than the other at some frequency. Your gains sound like they’re pretty close and when you turn up the volume when playing the good sub, you don’t hear that one clunk (reach it’s limits).
 

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Yes^^. You might have more room gain at sub location 1 than 2 or a bad sub.
Room gain is about 1 dB difference between the two sub locations. With the "clunking" sub actually in the spot with 1db room advantage. So that gain knob is about 0,5 dB lower then the other sub.

OK, just to be 100% sure I measured the level in front of the drivers and they are within 0,5 dB when having the volume knob at 50%.

Also interchanged the location of both subs and re-did Audyssey but problem stays with same subwoofer.
Seems to me that it's a subwoofer issue.

Tried calling Enrico and Brian but I don't know if they are available on Saturday. Otherwise probably have to wait till Monday.

Thanks all for the input and help.
 

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Room gain is about 1 dB difference between the two sub locations. With the "clunking" sub actually in the spot with 1db room advantage. So that gain knob is about 0,5 dB lower then the other sub.

OK, just to be 100% sure I measured the level in front of the drivers and they are within 0,5 dB when having the volume knob at 50%.

Also interchanged the location of both subs but problem stays with same subwoofer.
Seems to me that it's a subwoofer issue.

Tried calling Enrico and Brian but I don't know if they are available on Saturday. Otherwise probably have to wait till Monday.

Thanks all for the input and help.
Make a recording of the noise with your phone and send it to us via email.
 
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Was testing my new dual FV18 PC today and noticed something.
When playing the laser gun scene from Tron Legacy (where the main character is entering the world of Tron) I heard a light clunk in one of the FV18's.

This is happening with [email protected], subs 6db hot and using BEQ, subs on 12 hz, mid damping and rumble filter/ protection on.
When using low damping no problem at [email protected]

To rule out a weird Audyssey issue (could have been a ULF boost in one sub channel) I cross mapped the sub outputs with the MiniDSP.
The clunk was not happening on the other sub and I even went to -8db MV without any strange noise (after that I stopped because it was getting to loud).

-10MV with 6db boost is -4db, then some boost from BEQ (Tron Legacy profile, no other adjustments or house curve applied) makes it, around 0db?
I know it's a demanding scene but is this within spec? Looks like the woofer is bottoming out.
The difference between mid damping and low damping is the roll-off rate. The low damping does roll-off faster than mid damping. So the root cause is indeed subsonic signal that is filtered in low damping, but not in mid damping in 12hz signal range (as rumble filter only filter signals below 12hz).
 

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Just default configuration, no house curve or anything.
Just swapped the channels again and played every sub individually. Issue stays the same, not related to the channel.
Did you bypass the high pass filter on output 2 of your miniDSP (I'm assuming you did, but it doesn't hurt to check)? I discovered that output 2 has a high pass filter enabled by default. For the first 10 minutes of hooking up my miniDSP, I thought it was broken, but once I linked the outputs, it was all good.
 
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Did you bypass the high pass filter on output 2 of your miniDSP (I'm assuming you did, but it doesn't hurt to check)? I discovered that by default, output 2 has a high pass filter enabled by default. For the first 10 minutes of hooking up my miniDSP, I thought it was broken, but once I linked the outputs, it was all good.
I'm using the default output 1&3 for the subs, they don't have this filter like output 2&4. Thanks for mentioning.

Had some support from Brian and it could be something else then a bottoming out driver.
Could be something which is loose in the cabinet, we are in the process of figuring it out and I'm awaiting his instructions.
 

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How does an FV18 compare to a full Marty? I’m building a den/ht room that is 1300 cu ft and I’m trying to decide which way to go next year for a sub.

in the mean time I will throw my ED a7-350 or A7s-650 in there to hold me over.
 

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I'm using the default output 1&3 for the subs, they don't have this filter like output 2&4. Thanks for mentioning.

Had some support from Brian and it could be something else then a bottoming out driver.
Could be something which is loose in the cabinet, we are in the process of figuring it out and I'm awaiting his instructions.
Because it doesn’t seem like you’re approaching the limits of your subs (based on the “good” sub being able to play that scene even louder), it probably isn’t bottoming the driver. One thing that came to mind is to take two measurements of the bad sub. Take one with the rumble filter on and one with it off. I’m assuming the rumble filter is just a high pass filter to keep the driver from bottoming. Take the two measurements and see if the graph with the rumble filter on is different and shows a steeper low end roll off. Just taking a wild guess but maybe the rumble filter for whatever reason isn’t working on the “bad” sub and it actually is bottoming out because of that.
 

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I'm using the default output 1&3 for the subs, they don't have this filter like output 2&4. Thanks for mentioning.

Had some support from Brian and it could be something else then a bottoming out driver.
Could be something which is loose in the cabinet, we are in the process of figuring it out and I'm awaiting his instructions.
Because it doesn’t seem like you’re approaching the limits of your subs (based on the “good” sub being able to play that scene even louder), it probably isn’t bottoming the driver. One thing that came to mind is to take two measurements of the bad sub. Take one with the rumble filter on and one with it off. I’m assuming the rumble filter is just a high pass filter to keep the driver from bottoming. Take the two measurements and see if the graph with the rumble filter on is different and shows a steeper low end roll off. Just taking a wild guess but maybe the rumble filter for whatever reason isn’t working on the “bad” sub and it actually is bottoming out because of that.
 

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Because it doesn’t seem like you’re approaching the limits of your subs (based on the “good” sub being able to play that scene even louder), it probably isn’t bottoming the driver. One thing that came to mind is to take two measurements of the bad sub. Take one with the rumble filter on and one with it off. I’m assuming the rumble filter is just a high pass filter to keep the driver from bottoming. Take the two measurements and see if the graph with the rumble filter on is different and shows a steeper low end roll off. Just taking a wild guess but maybe the rumble filter for whatever reason isn’t working on the “bad” sub and it actually is bottoming out because of that.
That's a good one, actually the rumble filter is doing something cause when I turn it off the clunk happens with -15db MV.
With rumble filter on I can go till -10 MV.
 

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Seems to be solved! Was not a driver issue but probably something rattling in the enclosure. With the help of Brian I removed the amp en secured some screws on the amp. I also removed some larger glue residu on the outside of the ports. And moved the driver cable in another position.

Ran some 10hz clips and during that shaking the sound disappeared.

One of the above things seemed to have killed the rattle.
Tried the Tron clip with -8 dB MV and no clunk. Will do some more runs the coming days and see if it stays this way.

Definitely not bottoming out, Thanks to Brian from Rythmik and the help from here.
 

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E15 has been amazing so far. Huge upgrade for music and more than holds it's own for home theater. Couple of hanging wall picture casualties already.

Enjoying Hi damping so far, will look to integrate better with towers for 2 channel music going forward.

For musical blending,is it best to mess with the crossover on the AVR or the rear of the subwoofer? It's very close after an initial Audy run but haven't ventured off of the base 80hz crossover for LCR stage. Just want to dial in the two together a best as possible. Thanks again for the guide and tips. Time to rewatch and listen to a bunch of media.
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