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Discussion Starter · #1 ·
I have a pretty good setup - an Onkyo 797 powering Polk RM7200 speakers. What I have found is that on most recordings, I'm wanting to boost up the drums (personal preference). The bass levels are fine, so I don't want to just turn up the subwoofer. But I'd really like to shake the room with kick drums and the rest. I seem to be able to do this more effectively in my car (which just has the original car speakers in it) just by turning up the volume. I cannot just turn up the volume in my home theater however, since the sound seems to get muddied (correct adjective?) if I turn it up too high (it could be due to room accoustics, although I'm not sure). Don't get me wrong - I'm able to turn it up to pretty high levels (say, 70-80 db). It's just that the drums in particular aren't coming through impressively.


I think the main culprit is the source recordings; meaning, I don't think the drum volume level is set high enough during the recording (at least for my tastes).


At any rate, is there a solution to my problem? I thought that an equalizer might be a solution, but I've read nothing but negatives about them.


Any help would be appreciated.


Thanks.


-Gene
 

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Gene, my guess is that your speakers, in your room, emphasize and de-emphasize the frequencies that make the drums lose their impact while the slower attack and decay of bass notes seems to be boosted. The point is: your room sucks, but only at cretain frequencies. You need to fix this.


It may be speaker placement, room modes (including ratios of the 3 dimensions), need (gasp!) of an equalizer, room treatment, etc. or, as you said, the recording mixes themselves. (They are of different frequency ranges, as you no doubt already understand.) You can't change the recordings.


In any case, you need to change the overall respone of your system, which includes your room (all of it) and your head. The easier (and less preferable) way to do this is with electronics: you need to do a frequency-sweep test of your room, and cut the peaks with an EQ. (Resist the temptation to boost valleys.)


As you've heard, it's better to adjust the acoustics of the environment. Specific speaker locations excite specific frequencies at specific locations in every room. It can't simply be charted because every room is different. Elsewhere in this forum, members have posted simple programs that calculate these dimensions.


Sorry I'm not more specific, but I'm lazy, lucky, or both; my speaker setup sounds pretty good where I plunked them. Do a forum search, Gene. Try words such as "calculator", "dimensions", and "modes". I do know, by the way, that none of your room's dimensions either match, or are exact multiples of, one another.
 

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It's not the recordings - if it were, you would be just as unsatisfied in your car as at home.


Have you done anything about vibration management? Vibration negatively affects every component in your system, and since by far the biggest source of vibration is your speakers, the louder you play your system, the more the sound will degrade. Do a search for 'isolation' and you will find many tweaks you can try out, many of them very inexpensive or even free. Even in systems where there isn't any perceived problem, a relatively small effort towards vibraiton management can bring surprising results.


It also sounds like you haven't implemented any acoustic treatments for your room. You shoud actually tackle room acoustics before doing anything else. Trying to optimize your system before optimizing the acoustic environment is like tying to calibrate a TV with a smoke machine between you and it - you are not able to clearly 'see' what is actually comnig out of your system versus what is being created/destroyed by the room acoustics. There is a seemingly inifinite amount of info on room treatments out there - just do a search.


Best of luck,

Tweak
 

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It could be that your car amp, like lots of car amps, has a built in bass boost and your home system is actually reproducing the music more accurately than your car.


Just a thought...
 

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Discussion Starter · #5 ·
Thanks for the advice guys. I'm not sure about the room accoustics being the big problem only because when I play DVD's or even certain CD recordings, the drums or drum-like sounds (say, machine guns or the like) sound really good at times. That was what led me to think that it was a "problem" (again, only for my particular tastes) with the recording.


That's not to say that my room accoustics or speaker placements are ideal - I'm sure they could stand some improvement. But I'd be surprised if the improvement was drastic (although I'd love to be wrong!).


Also, I'm not sure how much time I have to devote to the research and implementation of trying to attain ideal accoustics (not to mention the wife acceptance factor). Perhaps there are some simple tests/fixes that I could try?


So, assuming that the accoustics and placement are "good enough" (i.e., take them out of the equation), is there anything else that can be done? In other words, suppose I just find that certain recordings do not boost the drum line enough. Can anything be done about that? Maybe what I'm asking is - is there any value in this case for an equalizer?


Just to clarify, what I'm trying to achieve is to be able to "feel" the drums. In other words, for certain types of music (mostly rock 'n roll), I like to be able to feel the kick drums and snare in my chest (I know it might sound disturbing, but that's the best way I can describe it! Hopefully, someone will know what I mean).


Thanks again.


-Gene
 

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You may want to isolate your speakers from your floor, especially if its a suspended wooden floor.

THis will give you a much clearer sound, although you may think it is a bit thin until you get used to the increased depth and lean-ness of the sound

Use a "soft" layer between speakers and stand or floor.

Coupling to the floor muddies the sound to a surprising degree.
 

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You could hire someone to to an acoustical analysis. It's really not that much. Then you would have a much better understanding of the issues of your system/room. Try HAA at www.homeacoustics.net . I think it can be had for around $200. Alot cheaper than guessing this or that.


Eddie
 

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Advice from a former drummer


You don't need to boost your sub's volume, you need more piston area (larger driver and/or multiple drivers) and serious watts from a quality amplifier (ie, one that can control a bass driver).


The kick drum has the most impact in the 40 - 80Hz region. If you boost the level or turn up a receiver's tone control (generic bass), you will muddy the bass (low frequencies). That's what you don't want for quality kick drum reproduction.
 

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Gene,


Try to borrow an external amplifier. If you add an external amp, you will get better transient responses from your system. The kick drums may be more distinct.


My prior receiver was an Integra (the same manufacturer as Onkyo); it was not the best with transients. As a pre-amp, it was excellent. In independent tests, the Onkyos run out of power at about 40 watts with all channels driven. This is not good for transient responses in the bass frequencies.


I agree with most of the prior comments and just wanted to add this possibility. In your position, I would not run out and buy an amp without testing the possibility without cost.


Bill
 

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If I'm not mistaken, the RM7200 speakers are the really small sat/sub combo. That could be your problem right there. Are you going throught the subs crossover or the receivers? Which frequency?
 

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You sit very close to car speakers so they're louder, and room gain starts at relatively high frequencies (~80Hz, above where you get bass slam).


You will need much more clean displacement from your home speakers to achieve the same listening levels. Turning it up doesn't work because your speakers are too small and start distorting early.


Replacing sub + main speakers is probably necessary; although it wouldn't hurt to play with your SPL meter to see if you have dips in the second octave (40-80Hz) at your listening position. Try moving the sub if that's the case.


If it's not already there, placing the sub in the corner will also allow it to work less (distort less) at a given playback level once you recalibrate - although I think achieving reasonable upper bass/lower midrange output levels is also going to be a problem. A higher cross-over may help with that but dictate a less optimal sub placement for integration.


Coupling (with spikes) your sub to the floor might help with some tactile feeling, although to get your chest cavity resonating you need high volumes which require big and/or lots of drivers.


HTH.
 

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Try first relocating your speakers. But I think you will get the right impact with other speakers. For me, Polks are muddy, almost by definition. Get yourself to a store where you can demo some Klipsch or other horn speakers.


You will be happily impressed!


KICK, KICK, SLAM! as fast and furious as you need it!


:D
 

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Discussion Starter · #13 ·
Wow! Great responses from all. Let me try to elaborate on my setup:


Facing the screen (wall), the room measures approximately 10 feet from left to right and about 15 feet from front to back. The room is in the basement on a raised floor (finished room). It also has a drop ceiling about 8 feet high. To the front is a wall onto which the video is displayed; to the right is a wall; behind is a kitchonette separated from the rest of the room by an "island" about 4-5 feet high; to the left of the seating area is another island separating the movie room from a play room; to the left of the screen is the entry (no door) between the movie room and the play room. Front speakers are placed to the left and right of the screen; center speaker is below the screen; sub is in the front right corner; surrounds are behind the listening area on the island (roughly a foot higher than eye level). None of the speakers are isolated (i.e., the front speakers are all on wooden stands; the rears on a wooden island); the sub simply sits on the floor (no spikes); none of the av components are isolated (in fact, my "rack" is shelving made of make-shift flimsy metal (aluminum?) - the kind you buy in walmart or some such place for storage and the like -- please don't flame me too bad for this! ;-) )


Regarding the speakers & receiver - I demoed quite a few in the stores and decided on the Polks and the Onkyo. While they may not be audiophile, I think they are each pretty good quality. As I mentioned in my previous post, they sound great with DVD movies and DVD-A (no muddiness at adequately high levels). This makes sense, as I would doubt that the combo could not be powerful enough for such a small room.


I just got a copy of Digital Video Essentials and an SPL meter. Does anyone know if that would give me a good starting point? Also, my speakers are set to "small" with sub for LFE for movie watching. I experimented a little by setting them to "large" for music, and I think I could tell the difference, but it was hard since there was no A-B comparison. Is "large' preferrable when listening to music? Note that music played during dvd movies sounds great even when set to small. Also, to answer someone's question - I believe the crossover is 80hz.


Thanks again.


-Gene
 

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Suggestion #1: adjust the sub phase:


Use a tone that is near the crossover frequency (so both the mains and the sub are playing), and adjust the phase control (pref. a continuous control) for best bass.


Suggestion #2: locate sub for best response:


Set up the sub where you sit (yes, in your seat, pref. at ear level) and crawl around the room at the sub's cone height, and listen for best bass. Now, set the sub in that place.
 

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Discussion Starter · #15 ·
Larry (and all),


Thanks for the suggestions. Although I understand #2, I am at a loss with #1. What exactly is the phase control? What tone would I use (eminating from where - the receiver?). Could you explain the process of adjusting the phase control so that I get the "best bass"? Sorry for the ignorance.


Thanks again!


-Gene
 

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Larry has two good suggestions, but they are listed in reverse order. Find the best spot for the sub first, then do the phase setup.
 

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Joe is right; I almost reversed the two steps when I posted, but we were heading out to dinner, and I was in a hurry. Well, that's my story, and I'm stickin' to it!


Gene, somewhere on the sub's control/input/output panel, there should be either a 0/180º switch or a variable knob labeled the same, and called 'phase'. 'Phase' refers to whether air is compressed (cone moving out of the box) or rarefied (cone moving into the box) at any given moment in time, and you want both the main speakers and the sub pressurizing the air at the same time, just like having left and right speakers 'in phase'.


When in phase, the pressure waves are in synch (like bi-polar speakers) and are said to be 'additive', whereas when out-of-phase, the pressure waves partially cancel one another (like di-polar speakers), or are said to be 'subtractive'. Obviously, it's more desirable to have the sound waves reinforce each other, so power isn't wasted moving cones and producing waves that won't be heard.


If your sub has only a switch, select whichever position produced greater bass sound during low notes. If a variable control, the proper setting can be harder to pinpoint, and you still need to go by best sound. The variations may not be very obvious, but take your time and experiment. You may change the setting several times before you settle on the best position.


The best source for a low tone might be from a test DVD/CD or even your processor's test tone. Someone else here might be able to help out better.
 

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Discussion Starter · #18 ·
Once again, thanks for all your help. I'll give your suggestions a try and hopefully it will work out.


Now back to my original question - if my equipment and placement are adequate, and it turns out that I just prefer louder drums (like at a live performance), what can be done to give them a boost (if anything)? Maybe I'm totally missing the point and I won't have to boost anything if the sub is setup correctly?


Thanks!


-Gene
 

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Once again, you will need to think about changing your speakers.;)
 

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Discussion Starter · #20 ·
I like Klipsh, but they always seemed a bit bright to me. And I never equated brightness to killer drum sounds (perhaps erroneously?). I'm still convinced that my speakers are fine (I did a lot of research and demos before I bought them), but if I can't improve things maybe I'll look into it.


Thanks.
 
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