150hz or 80hz?

[Alex2507]

hi guys i have a question about my system..... i have a onlyo 705 with definitive technolygy procinema800 sytem. so anyway i ran my onkyo's audeyssey automatic setup, and they set my mains and my surround to 150hz. is that right? i thought they had to at 80hz. can anybody help me with this, thanks..........if you guys want to know the specs of my system go to definitivetechnology.com,and look up the procinima 800 system. i cant post links cause this is my first post.

My vote goes to forgetting the auto set up and setting your crossover at 80hz. Def Tech's are very good speakers. These are rated for 57hz and you're only asking them to do 80hz. Then change stuff around if you think there is some sort of problem which there shouldn't be.

 

[autoboy]

Some very good setup tips for auto calibration. I would run those speakers at 90 or 100. It seems like that setting always is a little wonky on the auto calibration schemes.

 

[Davemcc]

I do not doubt that there are 4" drivers that can produce decent bass output. I am not familiar with the speakers you mention, but would imagine they are quite expensive if they do that, and not comparable to the Def Techs in question. Def Tech makes nice speakers, but the satellites (less than 5" driver) I have heard are lacking in the low end regardless of what the specs say. Again 57 hz. @ -2 db? -4 dB? They don't say.... Common marketing ploy.

You are absolutely right about the DefTechs. Their response is pathetic versus their claims. They start dropping like a rock at 110Hz and are -5dB @100. There seems to be no usable response by 80Hz. I learned something today, i.e. Deftech is not a reputable company that can be trusted.

http://www.soundandvisionmag.com/article.asp?article_id=1852&page_number=1

 

[ineedagirl69]

I think that goes for all companies but what ever. im leaving them at 90hz and will be playing with the crossovers from there, its ether 90 or 100hz.

 

[autoboy]

Any company that states frequency response with no +/-db cannot really be trusted. I love my Def Tech mythos twos, but there is no way they reach down to 45Hz like the specs show. i cross them over around 90 Hz.

 

[biguns]

Any company that states frequency response with no +/-db cannot really be trusted. I love my Def Tech mythos twos, but there is no way they reach down to 45Hz like the specs show. i cross them over around 90 Hz.

If you like the sound of your speakers, then that is good. It really doesn't matter anyhow when you are using a sub that is PROPERLY crossed over.

The situation described here is why I don't like 4" drivers, regardless of what the specs say. They force you to cross over way too high to avoid a large frequency dip. Anything over 100 hz, is not good to have your sub producing this. I am mostly concerned with 2-channel audio, with HT being of secondary concern.

If it is primarily HT use, then no big deal. Then I would cross over around 90 hz if possible, and deal with a small dip rather running too many higher freq through the sub.

 

[Exit]

As long as you have the subwoofer located with the front channels and are sitting at least six feet away, I think you can raise the aubwoofer crossover up to 150 Hz. If you go above that then you might run into high frequency (over 100 Hz) rolloff of the subwoofer. You would want to look at a frequency response graph for your subwoofer to see how much room you have to raise the crossover. I know it varies from subwoofer to subwoofer but they all cover at least an 80 Hz crossover.

 

[Alex2507]

I think that goes for all companies but what ever. im leaving them at 90hz and will be playing with the crossovers from there, its ether 90 or 100hz.

I really thought Def Tech was above that. Evidently I need to retract my prior post. It is good to see that you have a good plan from good info though.

-Alex

 

[ineedagirl69]

As long as you have the subwoofer located with the front channels and are sitting at least six feet away, I think you can raise the aubwoofer crossover up to 150 Hz. If you go above that then you might run into high frequency (over 100 Hz) rolloff of the subwoofer. You would want to look at a frequency response graph for your subwoofer to see how much room you have to raise the crossover. I know it varies from subwoofer to subwoofer but they all cover at least an 80 Hz crossover.

The onkyo's lpf of lfe lets me turn it uo to 120hz, and thats what i have it on. my sub go's up to 150hz but im using the lfe input so the onkyo controll's that.

 

[Exit]

It sounds like you have got the options, constraints and benefits down so you are free to experiment if you want. If you have settled on 120 Hz then it sounds like you are all set. Enjoy.

 

[ineedagirl69]

hi guys it's me again, thanks for helping me come up with the xover on my speakers. i settled with my fronts and center and 100hz ,my surrounds at 120hz and my sub and 120hz..........but now i have anothere problem, in some movies my sub is boomy. i have up front next to my entertainment stand, its about 3" from the side of the stand, so its not up againts it. and its near my room door, so theres a corner there. you thinks its standing waves? i dont have any traps for my walls or bass, but what can you guys recomend i do to reduce the boom? i have hardwood floors, and i already put an area rug under my sub.

 

[ineedagirl69]

anybody? please

 

[zhimbo]

anybody? please

Well, I usually recluse myself from advice-giving, but since you're impatient: Move the sub. Corner placement is done to reinforce low output. You probably have too much.

Sub position is, by all accounts, the biggest culprit in boom (assuming the sub is not overly boomy to start with, or set too high).

 

[no. 5]

you thinks its standing waves? i dont have any traps for my walls or bass, but what can you guys recomend i do to reduce the boom? i have hardwood floors, and i already put an area rug under my sub.

Carpet and rugs are useless for absorbing bass.

To reduce the boom on the cheep, the only solution would be to experiment with sub placement. Something that will help with that is test tones, as they will tell you what frequencies are the problem.
These may be useful in that regard, I have not used them myself, as I just found them a few minutes ago looking for cheep tones with the resolution needed; they appear to be correct (I ran a few of the previews through an RTA), and it would only cost about $14 to download 30-100Hz.

 

[TLS Guy]

hi guys i have a question about my system..... i have a onlyo 705 with definitive technolygy procinema800 sytem. so anyway i ran my onkyo's audeyssey automatic setup, and they set my mains and my surround to 150hz. is that right? i thought they had to at 80hz. can anybody help me with this, thanks..........if you guys want to know the specs of my system go to definitivetechnology.com,and look up the procinima 800 system. i cant post links cause this is my first post.

I rest my case. Those systems get you precisely wrong.

 

[ineedagirl69]

what are you talking about.

 

[TLS Guy]

what are you talking about.

I have been counseling against auto set up systems in numerous posts. Yours is another in a series of daft results.

EQ should be a last resort. Set you system up without any EQ. Set levels with an spl meter.

If your front speakers have reasonable power capability, set them to full, and add you sub gently in at the F3 point of your mains. See how that sounds first and then fine tune and experiment by ear.

 

[ineedagirl69]

Carpet and rugs are useless for absorbing bass.

To reduce the boom on the cheep, the only solution would be to experiment with sub placement. Something that will help with that is test tones, as they will tell you what frequencies are the problem.
These may be useful in that regard, I have not used them myself, as I just found them a few minutes ago looking for cheep tones with the resolution needed; they appear to be correct (I ran a few of the previews through an RTA), and it would only cost about $14 to download 30-100Hz.

are you sure carpets dont absorb sound? i always heard that any soft surface absorbs sound. should i remove it?

 

[ineedagirl69]

and do you need a spl meter to use that cd?

 

[no. 5]

are you sure carpets dont absorb sound? i always heard that any soft surface absorbs sound.

Carpets absorb sound, yes, but not the whole spectrum; the amount of sound that is absorbed by carpet changes with frequency, becoming of no use as an absorber below 125Hz.

should i remove it?

It shouldn't change anything if it's there or not.

and do you need a spl meter to use that cd?

It would help (and a notepad!), but the offending frequencies will be audible.