I hate my new subwoofer for certain low frequency

[JRS]

It's a port, driven hard and at low frequencies where the port takes over in tuning, there will be turbulence at high spl's.
The old video you linked was a driver issue not the port. In Erins video at 18.50, while sitting right next to it, he clearly states there is no noticeable port chuffing to be heard.
Also, these subs are supposed to be dsp tuned internally as to not overdrive the driver.
As @abdo123 stated, using the rug as you are doing in your photos, is changing the tuning of the sub.

This all sound a bit wonky. Have you read the manual on how too properly setup this sub?
1) You need to set the crossover THX toggle switch to off, then control the crossover from your AVR.
If you leave this on, you are now using the crossover built into the sub and the crossover from the AVR, that's neither good nor correct.
2) With regard to Extended or THX mode toggle, extended will give more output but with more distortion. So experiment accordingly.
3) With the level adjustment, turn it all the way down counter-clockwise until you hear a click. That will put it in the THX position, which is supposed to be 0dbs level.
4) Now you control the sub vol levels with your AVR.

Try setting it up as intended and see how that works out. If you still have issues, throw everything out the window and just set to what works, but don't expect more out of a 10'' with your current room size.

It occurs to me that there may be another factor involved besides port tuning, and that is that turbulence is better controlled by breaking the one pipe into several smaller pipes which can extend the fluid velocity before onset of frank turbulence. Or so my admittedly hazy recollection of fluid dynamics seems to recall. I'd see whether both can snuff out out a candle at the same volume (or blow smoke--wonder if tossing a chunk of dry ice in there would work?). amd naturally I'd also measure the impedance of both configs. I mention this just as it might be an incidental but useful piece of tech for addressing this chuffing issue--as the length port length gets crazy long in many cases where one is trying to increase the cross sectional area to stay well shy of c.

 

[Prana Ferox]

@JRS The rough problem of chuffing and air noise in general isn't in the bulk channel, it's at the edges, and specifically at the mouth where the pistonic volume interfaces with unmoving room air. Generally the best way of mitigating this (beyond using a bigger port area in the first place) is to round off your port ends, reducing the velocity as the cross-sectional area expands, and increasing the effective interface area. The horn-like flare of a Precision Port is the natural extension (pun somewhat intended) of this. The obvious downside is that this is additional space eaten out of cabinet volume that does not act as effective port; it's also more complex to make and takes up more exterior room on the cabinet face.

The Monoprice cutaways show the port is moderately rounded at both ends already.

Another real-world fix is to ensure any higher-frequency port noise is just not pointed at the listener, with the idea the HF noise is going to be radiated less. This doesn't work in the OP's case of playing test tones with one's face / mic right at the front of the sub, but in an actual room, you may mitigate this by just rotating the subwoofer. You don't want it pointing at too close a nearby wall / subwoofer or you're effectively just making a longer port.

Usually when you see designs do strange things with the bulk channel of the port it's to try to control port resonance, or to prevent other higher frequencies already in the cabinet from escaping out the port (generally not an issue in a sub.)

 

[Pogre]

@JRS The rough problem of chuffing and air noise in general isn't in the bulk channel, it's at the edges, and specifically at the mouth where the pistonic volume interfaces with unmoving room air. Generally the best way of mitigating this (beyond using a bigger port area in the first place) is to round off your port ends, reducing the velocity as the cross-sectional area expands, and increasing the effective interface area. The horn-like flare of a Precision Port is the natural extension (pun somewhat intended) of this. The obvious downside is that this is additional space eaten out of cabinet volume that does not act as effective port; it's also more complex to make and takes up more exterior room on the cabinet face.

The Monoprice cutaways show the port is moderately rounded at both ends already.

Another real-world fix is to ensure any higher-frequency port noise is just not pointed at the listener, with the idea the HF noise is going to be radiated less. This doesn't work in the OP's case of playing test tones with one's face / mic right at the front of the sub, but in an actual room, you may mitigate this by just rotating the subwoofer. You don't want it pointing at too close a nearby wall / subwoofer or you're effectively just making a longer port.

Usually when you see designs do strange things with the bulk channel of the port it's to try to control port resonance, or to prevent other higher frequencies already in the cabinet from escaping out the port (generally not an issue in a sub.)

Or in op's case get the appropriately sized subs for the room. A single 10" sub in a 4000+ cubic foot room is going to struggle and run into issues. I think even a pair of tens are undersized for that room.

 

[danzilla31]

Or in op's case get the appropriately sized subs for the room. A single 10" sub in a 4000+ cubic foot room is going to struggle and run into issues. I think even a pair of tens are undersized for that room.

Agreed. 100%

Also it's not sounding bad when op plays general content so I don't think there is an issue with the sub. Sounds like he just wants more deep bass. As you correctly point out you need bigger subs for that

I'm also even if the sub is damaged am wondering if the op by running lower frequency tones to max out the sub might have overextended that driver.

He basically did what Shady J and other reviewers do find what the limits are and kept doing that repeatedly. Any sub might have issues with that. Also I don't know if those subs were made to be sealed.

You can damage a sub by changing its tune if it's ports aren't meant to be sealed or if they are you don't change the DSP settings to protect the driver in the new configuration

 

[Spkrdctr]

As some have stated, there is nothing wrong with the sub. The first glaring issue is the sub is way, way too small for the room. For a 4000 sq ft room you will need 2 15 inch subs by a quality manufacturer if you want to feel it. One expensive big sub or 2 12 or 13 inch SVS subs will do very well too. What you have is like having a 4 inch full range speaker for your L/R speakers. They will not work in that room. Second, the method if testing is not telling you anything.

Get a lot more sub and you will be amazed. That is your only problem. Good Luck!

 

[Pogre]

The idea that you can plug the port and EQ the performance back with the same driver and cabinet volume is nonsense

Yes! Thank you. I meant to address that comment earlier. Plugging the port on that sub is not a good solution. It wasn't designed to be used like that. That suggestion was complete nonsense.

As some have stated, there is nothing wrong with the sub. The first glaring issue is the sub is way, way too small for the room. For a 4000 sq ft room you will need 2 15 inch subs by a quality manufacturer if you want to feel it. One expensive big sub or 2 12 or 13 inch SVS subs will do very well too. What you have is like having a 4 inch full range speaker for your L/R speakers. They will not work in that room. Second, the method if testing is not telling you anything.

Get a lot more sub and you will be amazed. That is your only problem. Good Luck!

Exactly. I'd be willing to just about bet a paycheck there's nothing wrong with that sub. He just needs 3 more of them for the performance he's expecting. A single 15 might work with careful placement and integration, and a pair would kill it. At minimum he needs a good pair of 12s for that room.

 

[Spkrdctr]

Yes! Thank you. I meant to address that comment earlier. Plugging the port on that sub is not a good solution. It wasn't designed to be used like that. That suggestion was complete nonsense.

Exactly. I'd be willing to just about bet a paycheck there's nothing wrong with that sub. He just needs 3 more of them for the performance he's expecting. A single 15 might work with careful placement and integration, and a pair would kill it. At minimum he needs a good pair of 12s for that room.

I think a pair of SVS PB4000 would do nicely! If you are not ruining light bulbs in the room, you do not have enough sub!

 

[Pogre]

I think a pair of SVS PB4000 would do nicely! If you are not ruining light bulbs in the room, you do not have enough sub!

I have a pair of ported 15s by my speakers and a dual 12 right behind my seat!

 

[Prana Ferox]

Yes, the OP is beholden to Hoffman's Iron Law and is finding out if you want flat FR down to 20hz or below, at THX volume, in a big space, you need serious subwoofer driver area, cabinet volume and wattage. There's a reason dedicated AV heads' homes look like they were furnished by lunatics.

Monoprice's own website shows the unit can be run sealed and to be honest I thought they included a plug. It doesn't defeat the HPF and doesn't really buy you anything other than maybe coping with room modes but you're probably better off doing that through the AVR.

If you need a plug (again, not the OP's actual problem) the best ones to get are the ones you get at Home Depot for testing piping like this:

.. but 3.5" is a weird size so it might be a hassle finding one, plus they're not that cosmetically nice, you might want to spraycan it before installing.

 

[Feyire]

My new monolith 10" v2 thx sub sounds good but honestly anything below 30hz where the port kicks in, it sounds like fart noises you make with your mouth

I can use the plug they included but it kills anything below 30hz. I don't understands monoprice / review saying this extends / rolls off after 20hz.

I stuffed a carpet in there to remove the fart noise and kinda get the low extension but honestly I could of just stayed with my cheap 75w 12" sub, that kinda played 30hz but the dual ports didn't fart

I wonder if there's something wrong with my unit. Using freq generator, https://www.szynalski.com/tone-generator/

I had an issue with one of my 10" V1 Monolith subs, which after contact with Monoprice support was RMA'd. I very quickly received a replacement after sending in a video of the issue, so kudos to them. The issue was a flapping-like sound coming from the port. I could consistently reproduce the issue with the following trailer, from approximately 0:25 until 1:15:

yeah, I guess it's port chuffing
only happens with tone / sin waves not movies or games but that could be because there's no 20hz content there

max output should be around 104db for 20hz, port noise is very early even at 85db

As others have previously pointed out, you are very likely overdriving the woofer and/or the amplifier with the sine wave generator at 20Hz. Since you have no issues while listening to music or watching movies, just enjoy it

 

[ex audiophile]

You should consider the Audioquest FartBuster Max subwoofer cable. What HiFi raves about the ability of the cable to cancel out the fartband frequency which is so ubiquitous and insufficiently neutralized by generic cables. At $899 it's a bargain

 

[MusicNBeer]

I just removed the woofer from my 10" V2 and tested it open air with a low level signal producing a few mm of excursion. There's definitely a rattle in the woofer. This is not normal as I've build several pairs of speakers using midwoofers that never do this. I'm going to contact Monoprice tomorrow about this. It sounds like the rattle is coming from the lead wire against the concave dust cap, but I don't know for sure.

 

[Pogre]

Do you have any type of room correction or setup routine? Did you run it with both subs? Most of those programs, for their faults, at least do a pretty good job setting distances and levels. If you have it, run it and go from there.

Where'd you go @tjtremor? Can you answer the questions above?

Any time you change or add something, especially subwoofage, you should really run setup and get a fresh calibration if you have it. At least to get your distances and levels set up. I'm curious how those 2 subs will work together for you. 2 is better than one. As long as they're similar designs (both ported or both sealed) and similar tuning you can get decent results.

Are you able to get bigger subs? That's really what you need, but if you can't we can help you get the most out of what you have. We're gonna need a little more participation from you tho!

 

[tjtremor]

Where'd you go @tjtremor? Can you answer the questions above?

Any time you change or add something, especially subwoofage, you should really run setup and get a fresh calibration if you have it. At least to get your distances and levels set up. I'm curious how those 2 subs will work together for you. 2 is better than one. As long as they're similar designs (both ported or both sealed) and similar tuning you can get decent results.

Are you able to get bigger subs? That's really what you need, but if you can't we can help you get the most out of what you have. We're gonna need a little more participation from you tho!

Yeah, I'm still on the forum daily. Reading on amps,usb dac. Was trying to find a usb dac with pre-amp + subwoofer pre-outs.

Using sr605, it does have eq,distance,x-over for sub, high pass for fronts, L+R summing for subwoofer,mic calibration,etc

I use bi-amp on the Klipsch, with the front left channel crapping out on the SR605 I'm forced into direct mode for bi-amp support.
My top unit there is for right channel subwoofer due to direct mode not summing L+R (for games).

I can switch them not bi-amp & use those AVR features.
Prob bigger sealed subs would be my next thing after new dac, but SVS have huge group delays. So prob not that.

 

[Pogre]

Omg. Get that rolled up whatever it is outta that port! Lol.

That can't be doing you any good. As far as bi amping goes, well, if you've been reading up on it here then you should already know it is not worth the effort. You gain nothing and add complexity to the system. Tho I'm not completely understanding what you mean by a channel being out? Is that why you're bi amping? Or are you just doing it to do it? What exactly... your left stereo channel is blown?

I have a SR6011 so I'm familiar with what you have to work with. Are you going to try to make both of those subs work with your setup? First thing you do after figuring out placement is run Audyssey again. You can flip to direct after that if you want, but I find that Audyssey actually does a pretty good job straightening out my bass. For 20 bucks you can get the app and limit the frequencies it eqs.

After that change your speakers to small, if necessary, and change your crossover to 80 hz and go from there. See how it sounds, and quit stress testing your subs like that. The info you're getting from doing that isn't really relevant for what you're trying to do, and at worst is leading you to fallacious conclusions.

 

[Pogre]

Bottom line is, you need bigger subs tho. No amount of port stuffing and stress testing is going to change that hard fact. For the bass you're after you need bigger subs. Period.

 

[tjtremor]

Omg. Get that rolled up whatever it is outta that port! Lol.

That can't be doing you any good. As far as bi amping goes, well, if you've been reading up on it here then you should already know it is not worth the effort. You gain nothing and add complexity to the system. Tho I'm not completely understanding what you mean by a channel being out? Is that why you're bi amping? Or are you just doing it to do it? What exactly... your left stereo channel is blown?

I have a SR6011 so I'm familiar with what you have to work with. Are you going to try to make both of those subs work with your setup? First thing you do after figuring out placement is run Audyssey again. You can flip to direct after that if you want, but I find that Audyssey actually does a pretty good job straightening out my bass. For 20 bucks you can get the app and limit the frequencies it eqs.

After that change your speakers to small, if necessary, and change your crossover to 80 hz and go from there. See how it sounds, and quit stress testing your subs like that. The info you're getting from doing that isn't really relevant for what you're trying to do, and at worst is leading you to fallacious conclusions.

The front left speaker output leaks noise. It's loud, we're talking 85db+. My best guess, that power stage is toast, leaking DC even on mute, nothing connected to the AVR.

In bi-amp mode, front L+R(tweeters) and surrounds rears L+R(woofers) get their input from L+R RCA. So not being able to use Front speaker terminals I have zone2 source line-out feeding back into multichannel for another set of working speaker terminals.

On the bonus side I have db control over each driver this way (-1 tweeters, +1woofers) + at high volume it's about 50% power from the AVR vs 100% power(90w limit per channel) and judging by that power stage crapping I'm trying to stay away from using 100% power per channel.

Not bi-amp with the Klipsch, it sounds different to my ears. There's less clarity,stage and the phase is different for sure.

My next year purchase will be usb dac, dedicated amp before changing the subs. Will retire these old AVRs.

 

[Slayer]

Omg. Get that rolled up whatever it is outta that port! Lol.

Agreed, I can't believe after all that has been posted here, he (OP) is still using that rolled up carpet matt thingy.
I'd be willing to bet dollars to doughnuts, he hasn't even attempted to set it up properly as I suggested in post #26.
Yes, the sub can be run as a sealed sub, it comes with a port bung. However, he will lose even more output which will undoubtably be even more disappointment for his needs or wants.

I think the OP first needs to resolve getting a properly working AVR and then worry about sub size upgrades. But even then, without thoroughly understanding the product and settings it may be a very long endeavor.

 

[coonmanx]

Seems like a bigger and better sub is being called for. There is no replacement for displacement...

I also have zero experience with using a sub or subs... but it seems that if a ported sub is not what the doctor ordered then maybe a sealed one is. Lots of choices out there. But for a large room I would think that a 12" unit would be better. Or units...

 

[Pogre]

Agreed, I can't believe after all that has been posted here, he (OP) is still using that rolled up carpet matt thingy.
I'd be willing to bet dollars to doughnuts, he hasn't even attempted to set it up properly as I suggested in post #26.
Yes, the sub can be run as a sealed sub, it comes with a port bung. However, he will lose even more output which will undoubtably be even more disappointment for his needs or wants.

I think the OP first needs to resolve getting a properly working AVR and then worry about sub size upgrades. But even then, without thoroughly understanding the product and settings it may be a very long endeavor.

No kidding. It's like none of the advice given in this thread is being considered or acted upon. And now we have an avr with a blown channel, bi amped speakers and confused connections...

I give up, lol.