messy at loud volumes

[PENG]

My bad, 0 for right, -0.5 for left

In that case volume at 70 to 75 is not too bad but getting close the the so called reference level. The Denon could still be clipping occasionally when playing music with high dynamics or with high input signal that you may get from sources such as tuner, internet radio, you-tube etc if you keep the volume in the 70's. I am beginning to think a 300W PC X 2 could help.

 

[TLS Guy]

In that case volume at 70 to 75 is not too bad but getting close the the so called reference level. The Denon could still be clipping occasionally when playing music with high dynamics or with high input signal that you may get from sources such as tuner, internet radio, you-tube etc. I am beginning to think a 300W PC X 2 could help.

I'm pretty sure, that if he plays loud dynamically compressed rock music with that amp, their will be a couple of blown mid range drivers at least.

 

[PENG]

I'm pretty sure, that if he plays loud dynamically compressed rock music with that amp, their will be a couple of blown mid range drivers at least.

I agree, but that's depends on where he set his master volume. Higher compressed rock also have much less dynamic peaks naturally so I guess it is thermal issues that you are referring to. Just to recap what Sam has told us so far below:

Speakers: F12's position 11 ft equilateral triangle.
Sitting distance: Let's assume that's the approx distance of the mic when he ran Audyssey
Calculated sitting pos 11ftXSine 60 degrees = 9.53 ft.
F12's sensitivity: 90 dB/2.83W/1M according to Stereophile
Nominal impedance: 6 ohms according to Revel website
Denon AVR Vol: 70 dB +, but let's assume 75 (-5 on the -79.5 to +18 scale)
Denon AVR level: 0dB for R, -0.5dB for L


Assumptions for calculating/estimating power output with Vol set to -5:

F12's nominal impedance 4 ohms instead of the 6 ohms specified by Revel

• SPL at sitting position, one speaker playing, vol set to =75-5=70dB (again, assuming Vol 0 gives 75 dB at the sitting position after Audyssey XT32 auto calibration).
• SPL drop at sitting position, assume 0 room gain = 10.5dB
• SPL corrected to 1 meter = 70+10.5 = 80.5dB
• Power required to produce 80.5 dB at 1 meter, 1 speaker playing = 0.22W (22.5W for 20dB peak)

I am not too sure after calibration watching watch blu-ray movies whether he will get 75dB or 85dB average at his listening position with volume still at 75. If it is 85dB then the calculated 0.22W requirement will jump 10X to 2.2W average, 220W for 20dB peak.

So depending on the material he's playing, we don't know for sure what the SPL he's actually getting at 1 meter from his F12's when he has master volume set to 75 dB.

If highly compressed rock music will have much higher average power requirement at the same volume setting but it also would not have much dynamic peaks. So are you saying the mid range drivers cannot handle a more or less constant power of several watts? Again, I do realize it is more of a thermal issues for such compressed music, but clearly if he keeps the volume below 75 there is just no way the Denon would be delivering any where near 10W per channel average, with no much peaks to worry about for such music. Even ghetto blaster can blast rock music all day without destroying themselves right? I know there is a different explanation for that though.

 

[KEW]

PENG, I don't want to speak for TLSGuy, but I suspect the following two paragraphs capture his concern:

This brings me to my last point. It is a three way. The cross to the mid range driver is 575 Hz. By far from the lowest crossover point around, but that mid mid range driver will still be handling close to half the power. This is the problem with mid range drivers, they are small and have to handle a lot of power. In addition there is not a lot of cone excursion to cool the voice coil. The result is that the voice coil heats and the resistance goes up. This results in reduced output from the mid range as the volume is increased. This is called dynamic thermal compression. This is common in these types of designs at power. I would bet that this problem is a good deal of your muddiness issue at power.

...

I would be careful and be a bit more circumspect about the power you want to demand from those speakers, other wise I see blown mid range drivers and or a blown receiver in your future.

These concerns do, somewhat, contradict the notion that a sub would take the problematic load off of the speakers.

 

[PENG]

PENG, I don't want to speak for TLSGuy, but I suspect the following two paragraphs capture his concern:

Thanks Kurt, I did read that part and understand the concerns. My question to him though, is that after I ran some calculations, Sam is only loading the Denon and the speakers a few watts average (or RMS as commonly referred to incorrectly but generally accepted) so is he really saying that those mid range drivers can't handle such low wattage on a continuous basis? My calculations are done very conservatively, didn't even factor in room gain, based on 4 ohms nominal, among other things.

 

[PENG]

Sam, when you said the music sounded messy, what kind of music? Also what kind of media, I mean, CD, BR, DVD, digital files on computer, streaming, BR and/or DVD movies in DD, DTS? Did it sound messy regardless? I also don't recall you told us what you meant by "messy". if you can provide a little more specific description, it may help us narrow things down for you.

 

[Sams]

Sam, when you said the music sounded messy, what kind of music? Also what kind of media, I mean, CD, BR, DVD, digital files on computer, streaming, BR and/or DVD movies in DD, DTS? Did it sound messy regardless? I also don't recall you told us what you meant by "messy". if you can provide a little more specific description, it may help us narrow things down for you.

Music is streamed via USB to the denon. The usual streaming services. Hip hop, electronic, rock, alternative. Lately I've been using Amazon prime music which I assumed was 320 but just found out is 256 MP3. Before my original post I popped in my tycho dive cd and that was clearer at volume but still not satisfying. What I mean by messy is that the instruments seem to mix together and the bass seems to be the biggest distortion.

For movies it's mostly streaming from the bluray player, Netflix & Amazon prime. Reciever is set to stereo. I experiment with dynamic eq and dynamic volume(light) but it never really sounds great either. I'll be trying a bluray for the first time with these particular speakers tomorrow at moderate volumes, with the reciever set to stereo.

I haven't been able to crank the system yet again with family around for holidays, but I did get a chance to move the speakers away from the corners and the ports are now 6 inches from the wall. Bass has improved at moderate volumes, curious to see what it will sound like cranked up.

Edit: clarity

 

[PENG]

Music is streamed via USB to the denon. The usual streaming services. Hip hop, electronic, rock, alternative. Lately I've been using Amazon prime music which I assumed was 320 but just found out is 256 MP3. Before my original post I popped in my tycho dive cd and that was clearer at volume but still not satisfying. What I mean by messy is that the instruments seem to mix together and the bass seems to be the biggest distortion.

For movies it's mostly streaming from the bluray player, Netflix & Amazon prime. Reciever is set to stereo. I experiment with dynamic eq and dynamic volume(light) but it never really sounds great either. I'll be trying a bluray for the first time with these particular speakers tomorrow at moderate volumes, with the reciever set to stereo.

I haven't been able to crank the system yet again with family around for holidays, but I did get a chance to move the speakers away from the corners and the ports are now 6 inches from the wall. Bass has improved at moderate volumes, curious to see what it will sound like cranked up.

Edit: clarity

Thanks for the feedback.

Can you pull the speakers even further from the wall? 6 inches is still much too close. Below is what one professional commented in his review:

http://www.soundstage.com/revequip/revel_concerta_f12.htm

"My biggest concern when I unpacked the F12s was their size. My listening room measures 16'L by 12'W and has a 7 1/2" ceiling. Although it provides the perfect environment for the PSB Image 4T speakers that I use as my reference, I was uncertain if the pair of 8" woofers employed by the F12s would cause the bass to sound bloated or congested in my room. I ended up positioning the F12s 36" in from the side walls, 30" from the front wall, and 60" apart. In this location, I heard nothing but deep, well-controlled low frequencies. In fact, even when I really cranked up the volume, the bass never obscured what was happening in the music."


After that, I think you should try out some high quality source material before we continue troubleshooting. if you do not have any high resolution/lossless digital files to play or stream then at least try some Telarc CDs, preferably jazz and orchestral types of music. Blue ray live concerts should be good too.

 

[Sams]

Update. I seem to be resolving the issues. I've done a little of what everyone has suggested. I'm also going back to CDs for music and blurays for movies.

Now I did get the revel b1 (http://www.revelspeakers.com/productdetail/~/product/b1.html) to experiment with. I know I know, but I low balled for it and got it half off msrp. If this is the final solution I'll buy a pricey Id sub later on. Right now it is in the front right corner of the room.

What crossover should I use? Is it not safe to go past a 60hz crossover like tls mentioned? So far I've experimented with a 40 and 60hz crossover. The lpf is 120hz set by the denon. Audyssey set the sub to -5.0db. As of now I can say the clipping issue is long gone. Also, does rear wall clearance not matter anymore with the f12s?

 

[PENG]

Update. I seem to be resolving the issues. I've done a little of what everyone has suggested. I'm also going back to CDs for music and blurays for movies.

Now I did get the revel b1 (http://www.revelspeakers.com/productdetail/~/product/b1.html) to experiment with. I know I know, but I low balled for it and got it half off msrp. If this is the final solution I'll buy a pricey Id sub later on. Right now it is in the front right corner of the room.

What crossover should I use? Is it not safe to go past a 60hz crossover like tls mentioned? So far I've experimented with a 40 and 60hz crossover. The lpf is 120hz set by the denon. Audyssey set the sub to -5.0db. As of now I can say the clipping issue is long gone. Also, does rear wall clearance not matter anymore with the f12s?

I would go with 80 Hz. If the F12 sounds good where they are now, then leave them there. The b1 should help but to help more you probably need at least two of them.

 

[Sams]

I would go with 80 Hz. If the F12 sounds good where they are now, then leave them there. The b1 should help but to help more you probably need at least two of them.

Thanks. Revel recommended 80hz as well. My current placement of the speakers is 30 inches from the back wall. I've been using tidal hifi and the speakers sound much improved with the subwoofer. I can now turn them up as loud as I want and the sound is clear the whole way. Bass is now clear but I do not feel it(obviously). Right now I feel convinced the amp was clipping without the subwoofer/not symptoms of the speakers being in a not optimal position for bass.

I am going to try the sub crawl when no one is home to further experiment. So far I've only tried the front left and right corner.

In your opinion what are the cheapest 4 subwoofers you could recommend to pressurize my basement? I was thinking of putting one in each corner of the 18x18 "room" of the basement.

 

[PENG]

Thanks. Revel recommended 80hz as well. My current placement of the speakers is 30 inches from the back wall. I've been using tidal hifi and the speakers sound much improved with the subwoofer. I can now turn them up as loud as I want and the sound is clear the whole way. Bass is now clear but I do not feel it(obviously). Right now I feel convinced the amp was clipping without the subwoofer/not symptoms of the speakers being in a not optimal position for bass.

I am going to try the sub crawl when no one is home to further experiment. So far I've only tried the front left and right corner.

In your opinion what are the cheapest 4 subwoofers you could recommend to pressurize my basement? I was thinking of putting one in each corner of the 18x18 "room" of the basement.

I think the cheapest ones by established brands would come from HSR, SVS and Rythmik. For SVS, either the SB2000X4 or PB2000X4 would work depending on the types of music you listen to. If you are 50/50 HT and music and don't care about classical music then probably the PB2000 will satisfy you more.

I still don't believe your messy bass problem was due to clipping at all, because the Denon should only clip momentarily during the occasional very high peak moments so that would not have given you the steady messy bass you were hearing. If the Denon was really clippping steadily, it wouldn't be just messy bass. In fact it should have been the mids and highs that would cause you to turn the volume down in a hurry. It has to be the speaker's bass capability limits, and their positioning (too close to the wall at the time) that gave you the problem.

Conversely, if you were getting that messy bass only when you over drove the Denon, then it was the culprit. Based on the information you provided, you apparently were not over driving the Denon even though you could have, given that you have a big room.

Edit: Forgot to include PSA, two of their XV15SE could probably do the trick for you but they are not on sale at the moment.

If you prefer 4, take a look of the low price Rythmik LV12R:

http://www.rythmikaudio.com/LV12R.html

You can get 4 for a little over 2K.

 

[highfigh]

Thanks. Revel recommended 80hz as well. My current placement of the speakers is 30 inches from the back wall. I've been using tidal hifi and the speakers sound much improved with the subwoofer. I can now turn them up as loud as I want and the sound is clear the whole way. Bass is now clear but I do not feel it(obviously). Right now I feel convinced the amp was clipping without the subwoofer/not symptoms of the speakers being in a not optimal position for bass.

I am going to try the sub crawl when no one is home to further experiment. So far I've only tried the front left and right corner.

In your opinion what are the cheapest 4 subwoofers you could recommend to pressurize my basement? I was thinking of putting one in each corner of the 18x18 "room" of the basement.

Did you place the speakers according to the recommendations, or by listening? If you used the recommended locations, I would strongly recommend placing some kind of weak tape on the floor and moving the speakers so they achieve the sound that's best. They can't know what is in your room (or not in the room) and this means they could only generalize. Each room is somewhat different WRT the effects on the acoustics, so it's best to place the speakers where they sound best. If that location is a problem for traffic patterns and normal life, find a way to mark the location and move them out of the way until you want to do some serious listening.

A square room is not optimal.

I saw that you mentioned the level on the Denon- did you set a limit on the maximum level? I NEVER allow an AVR to go to the maximum level if it has the ability to be limited. I do this for several reasons:

It's not much different from mashing the gas pedal to the floor and waiting for parts to fly through the hood because it's almost impossible to achieve clean power unless the input signal level is low and this only happens when the output from a phono cartridge is low, the source device has a level control and it's set lower than normal or if a song begins/ends gradually. When there's no signal, the tendency is to increase the volume setting before doing anything else. Once it has been determined that the source selected was wrong, changing to the correct one results in high SPL and the death of something, whether speakers or amplifier, it doesn't really matter.

You can't be sure if the signal getting to the speakers is distorted, or not. If you're using your ears, you need to know that we can't hear most distortions until they reach whole numbers of percentage. We CAN, however, hear the results from frequencies making the speakers do a dance they shouldn't and from the voice coil impacting the back plate of the magnet assembly when that's a possibility. We can also hear mud, when it results from a variety of factors, such as allowing the level control to be set too high, bad speaker placement/configurations, etc.

I would go back to the beginning and listen to only two speakers, at first. If you can't get a good sound with two, you WON'T get a good sound with more of them.

 

[KEW]

In your opinion what are the cheapest 4 subwoofers you could recommend to pressurize my basement? I was thinking of putting one in each corner of the 18x18 "room" of the basement.

For greatest value, I would consider these (ordered by increasing price).

Dayton Audio SUB-1200 ($480 for four, shipping included)
http://www.parts-express.com/dayton-audio-sub-1200-12-120-watt-powered-subwoofer--300-629
http://www.hometheatershack.com/forums/speaker-subwoofer-reviews/71766-dayton-audio-sub-1200-subwoofer-review.html

Dayton Audio SUB-1500 ($792 for four, shipping included)
http://www.parts-express.com/dayton-audio-sub-1500-15-150-watt-powered-subwoofer--300-634

Outlaw Audio Ultra-X12 ($1998 for four, shipping not included)
https://www.outlawaudio.com/mofcart/Holiday2015.html
http://www.outlawaudio.com/products/ultra.html
http://www.audioholics.com/subwoofer-reviews/ultra-x12-subwoofer

 

[Sams]

Did you place the speakers according to the recommendations, or by listening? If you used the recommended locations, I would strongly recommend placing some kind of weak tape on the floor and moving the speakers so they achieve the sound that's best. They can't know what is in your room (or not in the room) and this means they could only generalize. Each room is somewhat different WRT the effects on the acoustics, so it's best to place the speakers where they sound best. If that location is a problem for traffic patterns and normal life, find a way to mark the location and move them out of the way until you want to do some serious listening.

A square room is not optimal.

I saw that you mentioned the level on the Denon- did you set a limit on the maximum level? I NEVER allow an AVR to go to the maximum level if it has the ability to be limited. I do this for several reasons:

It's not much different from mashing the gas pedal to the floor and waiting for parts to fly through the hood because it's almost impossible to achieve clean power unless the input signal level is low and this only happens when the output from a phono cartridge is low, the source device has a level control and it's set lower than normal or if a song begins/ends gradually. When there's no signal, the tendency is to increase the volume setting before doing anything else. Once it has been determined that the source selected was wrong, changing to the correct one results in high SPL and the death of something, whether speakers or amplifier, it doesn't really matter.

You can't be sure if the signal getting to the speakers is distorted, or not. If you're using your ears, you need to know that we can't hear most distortions until they reach whole numbers of percentage. We CAN, however, hear the results from frequencies making the speakers do a dance they shouldn't and from the voice coil impacting the back plate of the magnet assembly when that's a possibility. We can also hear mud, when it results from a variety of factors, such as allowing the level control to be set too high, bad speaker placement/configurations, etc.

I would go back to the beginning and listen to only two speakers, at first. If you can't get a good sound with two, you WON'T get a good sound with more of them.

I'll try this. What limit did you set? I basically averaged out the placement of the online magazine reviews. I'm now going to try the rule of 1/3 placement. So that would put the speakers about 6 feet apart and 6 feet from the side walls. I touched on this earlier but the room is an 18x54 rectangle and that opens up into another section of the basement as well. The listening area is about 18x18 at the top of the rectangle.

 

[KEW]

I recommended subs based on 18X18 room (two of any of them would have an easy time with 8-9' ceilings and 18x18). 18x54 is a large space. While I think 4 SUB-1200s would do fine for music, if you want a fairly strong LFE experience for HT, you should skip them for the 1500s or Outlaws. If HT was your main concern, then we'd be talking around $4000 for 4 and still might not pressurize the room at 16Hz!!!
That is a big room and you'll want to play with positioning - locating the sub as close to the listening position as is practical is not a bad idea to get the max impact out of your subs, while corner placement will best help the output at bottom frequencies.

 

[Beave]

I still don't believe your messy bass problem was due to clipping at all, because the Denon should only clip momentarily during the occasional very high peak moments so that would not have given you the steady messy bass you were hearing. If the Denon was really clippping steadily, it wouldn't be just messy bass. In fact it should have been the mids and highs that would cause you to turn the volume down in a hurry. It has to be the speaker's bass capability limits, and their positioning (too close to the wall at the time) that gave you the problem.

Conversely, if you were getting that messy bass only when you over drove the Denon, then it was the culprit. Based on the information you provided, you apparently were not over driving the Denon even though you could have, given that you have a big room.

You can get "messy bass" without hard clipping when the amp is pushing too much current, leading to its unregulated power rails sagging. This can happen when the speaker has a low impedance in the bass, the content is bass heavy, the levels are loud, and the amp's power supply is not up to snuff. As you turn it up in cases like this, the bass just gets muddier and muddier due to the power supply rails drooping with the heavy currrent draw. I've heard it in practice and seen it fixed, so to speak, by switching to an amp with a more robust power supply (bigger transformer and higher value filter caps on the rails).

 

[PENG]

You can get "messy bass" without hard clipping when the amp is pushing too much current, leading to its unregulated power rails sagging. This can happen when the speaker has a low impedance in the bass, the content is bass heavy, the levels are loud, and the amp's power supply is not up to snuff. As you turn it up in cases like this, the bass just gets muddier and muddier due to the power supply rails drooping with the heavy currrent draw. I've heard it in practice and seen it fixed, so to speak, by switching to an amp with a more robust power supply (bigger transformer and higher value filter caps on the rails).

Not sure what your point is. My point was that I did not believe it was his AVR clipping causing his messy bass because of his reported volume position, sitting position and speaker level setting after running room EQ. So I believe his messy bass was speakers, room, and placement related. Numbers and calculations don't lie and I did do my calculations (presented briefly in earlier post) so I am 99% sure the Denon did not run out of juice on him. I also mentioned that his AVR could also be the problem as he has a rather large room and by now we should all know his speakers, though considered not hard to drive, do have some impedance dips. Keep in mind too we are talking about two channel here, not all channel driven stereo.

Fyi I had measured the output voltage and current of my previous Denon AVRs (3805 and 4308) and found they had no trouble pushing well over 10A into my speakers with no sign of clipping at all, and SPL peak well over 100 at 1 meter, and that's using bass drum and cymbals heavy material. During the experiment, I A/B the measurements and listening with two different power amps and the readings were essentially the same.

The way you tried to explain could also make sense, when you referred to "without hard clipping", did you then mean "soft clipping" such as the scheme used in NAD units? As far as I know, his Denon AVR-4520 does not have such feature, if it is over driven to a certain point its protective circuit would just activate to protect the unit.

Your point on soft clipping is well taken as it is a valid point, but it really wouldn't apply in this case.

 

[Sams]

Hey guys. No news on the sub-still using the b1.

Interesting thing happened today. I think my music plays cleaner with the plasma tv off. I hope I'm not getting into audio foolery here.

My 3 components are plugged into a cheap 6 outlet Tripp lite surge protector. Today I switched the outlet configuration. I moved the denon plug from the second outlet to the first, and the lg plug from the first to second outlet. The third outlet is for my bluray player, the remaining 3 are not used.

Any way, I downloaded London grammar's "If you wait" album for offline listening on my tidal hifi app. I then airplayed to the denon as usual. I always listen to music with the plasma on so I can see the denon user face. With audyssey engaged as well as dynamic eq, I toggled the volume up to 65. The plasma would flicker and sometimes show green flashes at this volume (freezing the music momentarily as well) before returning to normal. It seemed to occur at the most dynamic parts of the music, but take that with a grain of salt. Turning off the plasma helped alleviate the issue considerably, but not completely. Turning the plasma back on, I toggled the volume down to 32.5 with no issues.

Overall the music seemed to be cleaner and more dynamic when the denon was moved to the first outlet and the plasma was turned off.

Should a receiver and plasma not be plugged into the same power strip? Also the denon is sitting about 6 inches below the plasma which is wall mounted. Its always warm.

I should note that all my black cables(hdmi, toslink, power) are tied for a clean look. My white cables(speaker, subwoofer, Ethernet) are free.

 

[PENG]

Hey guys. No news on the sub-still using the b1.

Interesting thing happened today. I think my music plays cleaner with the plasma tv off. I hope I'm not getting into audio foolery here.

My 3 components are plugged into a cheap 6 outlet Tripp lite surge protector. Today I switched the outlet configuration. I moved the denon plug from the second outlet to the first, and the lg plug from the first to second outlet. The third outlet is for my bluray player, the remaining 3 are not used.

Any way, I downloaded London grammar's "If you wait" album for offline listening on my tidal hifi app. I then airplayed to the denon as usual. I always listen to music with the plasma on so I can see the denon user face. With audyssey engaged as well as dynamic eq, I toggled the volume up to 65. The plasma would flicker and sometimes show green flashes at this volume (freezing the music momentarily as well) before returning to normal. It seemed to occur at the most dynamic parts of the music, but take that with a grain of salt. Turning off the plasma helped alleviate the issue considerably, but not completely. Turning the plasma back on, I toggled the volume down to 32.5 with no issues.

Overall the music seemed to be cleaner and more dynamic when the denon was moved to the first outlet and the plasma was turned off.

Should a receiver and plasma not be plugged into the same power strip? Also the denon is sitting about 6 inches below the plasma which is wall mounted. Its always warm.

I should note that all my black cables(hdmi, toslink, power) are tied for a clean look. My white cables(speaker, subwoofer, Ethernet) are free.

I wouldn't worry much about the interference but the power draw on the outlet. It is better to plug the big Denon to a dedicated outlet so it does not have to share with other big consumers such as a large screen plasma TV. The AVR-4520 has a fairly large power supply, large enough to deserve a 15A circuit all for itself if possible. Again, at volume position 65, that AVR should not clip, not for the kind of music you listen to anyway, but if you load the 15A circuit up too much especially if the feed to the receptacle is long, the Denon may not be getting the 120V that it needs to do its best. I would also bypass the Tripp Lite, plug the Denon directly into the outlet for best performance.

By the way, would you please do some of us a favour and change the volume scale to relative so it will read from -79.5 to +18 dB?