Team-BHP - The Home Theater thread

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even though my fronts are capable of 39Hz

they wont really be - the figures quoted by the manufacturer are usually +/-3db - and a crossover point needs to be one octave above its lowest point which allows the speaker a decent roll off - so if the frequency response is quoted as 39hz to 20khz then to preserve the speaker you should be setting it at one octave above 40hz (rounded off from 39hz) which is 80hz anyway

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LPF of LFE: 120 Hz

so you are low passing the subwoofer at 120hz ie allowing frequencies below 120hz to pass through while rolling off any frequencies above 120hz and then you have the front high passed at 60hz which allows frequencies above 60hz to pass while reducing the frequencies below 60hz at the rate of the crossover slope - this is definitely not ideal because between 60hz and 120hz you will be having huge peaks and this will cause the sound to be boomy and inaccurate (even though you might prefer it like this) this is because the overlapping frequencies are played by both speakers and hence they cannot integrate into a flat response

the most accurate way is to actually have an underlap of frequencies for example the sub low pass at 60hz and the main speakers high pass at 80hz (frequencies selected as a quick example for demonstration and not as a calculated figure) the reason for this is that the crossover does not reduce the frequency like a brick wall - it reduces it at the rate of the slope - so for example if you have a slope of 12db/octave on your main speaker high pass at a frequency of 80hz you will still have 40hz (which is one octave lower than 80hz) playing at 12db lower - so it stands to reason that around 60hz would be more-or-less 6db lower. Where the frequencies are played by both speakers you would have those particular frequencies bumped up because they play at x(spl) but because another speaker plays it as well it would be playing at 2x(spl)

then theres the problem of increasing levels - the decibel system is actually a logarithmic system hence we know that 3db is an actual measured doubling of your actual levels even though your brain does not perceive it as thus - but doubling anything will give you a 3db increase - so your amplifier has to work twice as hard wherever you increase anything by 3db .... and the same goes for EQ ie any frequency that you increase makes the amplifier work harder at the increased frequency - this means it will run hotter and not last as long ... as well as play with strain and distortion (which you sometimes wont hear but its there all the same)

so yep you can set it how you like because its your ears you need to please but please do find out a bit about what each setting does and the effects it has on the sound because this will help you to play the sound at safe levels and preserve your equipment for longer .... and it doesnt take much to do a few google searches and read a bit on all these things and it will be informative and educational as well and it cannot be a bad thing if helps you to get things right and increase the long term enjoyment of your equipment

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Originally Posted by naughty001 (Post 2655581)

well how you set things is up to you but to me your settings are all over the place

heres a few things to remember

THX recommends a crossover point of 80hz at 24db/octave - 80hz is a good point to stick to if your speakers can handle this

they wont really be - the figures quoted by the manufacturer are usually +/-3db - and a crossover point needs to be one octave above its lowest point which allows the speaker a decent roll off - so if the frequency response is quoted as 39hz to 20khz then to preserve the speaker you should be setting it at one octave above 40hz (rounded off from 39hz) which is 80hz anyway

so you are low passing the subwoofer at 120hz ie allowing frequencies below 120hz to pass through while rolling off any frequencies above 120hz and then you have the front high passed at 60hz which allows frequencies above 60hz to pass while reducing the frequencies below 60hz at the rate of the crossover slope - this is definitely not ideal because between 60hz and 120hz you will be having huge peaks and this will cause the sound to be boomy and inaccurate (even though you might prefer it like this) this is because the overlapping frequencies are played by both speakers and hence they cannot integrate into a flat response

the most accurate way is to actually have an underlap of frequencies for example the sub low pass at 60hz and the main speakers high pass at 80hz (frequencies selected as a quick example for demonstration and not as a calculated figure) the reason for this is that the crossover does not reduce the frequency like a brick wall - it reduces it at the rate of the slope - so for example if you have a slope of 12db/octave on your main speaker high pass at a frequency of 80hz you will still have 40hz (which is one octave lower than 80hz) playing at 12db lower - so it stands to reason that around 60hz would be more-or-less 6db lower. Where the frequencies are played by both speakers you would have those particular frequencies bumped up because they play at x(spl) but because another speaker plays it as well it would be playing at 2x(spl)

Thanks Naughty001!
It is now clear to me, and it seems that you have good experience with sound technology. (are you by any chance a sound engineer?).
What you have said is quite logical to me. I did experiment with the crossover set at 80 Hz also for the fronts and the center as per THX recommendations, but I guess the bass overlap was creating the problem.
So if I understand the settings correctly, I should set the fronts / center / Surround all to cross over at 80 Hz and the sub LPF LFE level at 60 Hz, which will intentionally leave a gap of 20 Hz in the frequency band, but allow better clarity in the sounds due to the differentiation of the frequencies.
Suppose that I put the LPF level at 80Hz and the main speakers at crossover 80 Hz, will it still have the same problem and not be able to differentiate.
I also read a lot of discussions on the Audyssey forum:
Crossover frequency : Ask Audyssey
Where the engineer recommends to set all speakers to 80 Hz crossover and the LPF to 120 Hz so I am a little confused!
Appreciate your feedback and though I am no audiophile, I would like to get the best sound output from my system and I have realized that these settings make a huge difference in sound quality!

Thanks!

Regards,
Behemoth

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Suppose that I put the LPF level at 80Hz and the main speakers at crossover 80 Hz, will it still have the same problem and not be able to differentiate.

You will probably have a slight peak at 80hz but this will still be way better than having a broader peak in the range but it will also be easier to address using the EQ of the receiver if it has manual adjustment capability

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Where the engineer recommends to set all speakers to 80 Hz crossover and the LPF to 120 Hz so I am a little confused!

I have no idea why he recommends that so i can only try and guess why he does :

1) He probably means you do this before the audyssey setup because the audyssey will be adjusting for these anomalies .... remember that the audyssey works on measured in-room settings so if the audyssey will measure then adjust for all perceived speaker problems

2) The other alternative is that he means to do the low pass filter setting o the subwoofer crossover itself because the settings on the receiver will most likely be lower BUT the general rule for this is to actually have the subwoofer crossed as high as it will go and let the receiver get the actual crossover point required according to how the other speakers are set

The thing is though in every other respect the audyssey advisers advice is spot-on and the only thing that does not make sense to me is this issue of creating the overlap between full range speakers and LFE

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(are you by any chance a sound engineer?).

I have been a hobbyist as well as a nightclub DJ for a long time. So while i am not a sound engineer I do have some experience in setting up live bands and public address systems as well as audio playback systems from a very early age so while i do not have any formal qualifications i do have a bit of what you could call on-the-job experience in these matters

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So if I understand the settings correctly, I should set the fronts / center / Surround all to cross over at 80 Hz and the sub LPF LFE level at 60 Hz, which will intentionally leave a gap of 20 Hz in the frequency band, but allow better clarity in the sounds due to the differentiation of the frequencies.

that is generally the theory ..... in fact crossover design in speakers depend on this principle ie with butterworth filters the crossover point is calculated to be where the intersection between the drivers is at a point 3db lower than flat levels while in a linkwitz reilly it is calculated at a point where its 6db lower so whilst those exact values quoted in the example might not be 100% correct they are close enough as an example of the type of underlap that needs to occur to create a flat frequency response

the importance of a flat frequency response is that it allows you to hear most sounds as they naturally occurred ie the recording will make the relevant frequencies louder or softer when required and this makes for a more realistic experience with music and movies - for example the way i have my system setup now just with proper adjustment and speaker positioning it sounds as if sounds are just hanging in the air between the speakers as if the artists really were there and playing their instruments and vocalists sound remarkably lifelike .... the closer to a flat in-room response you are the better this imaginary soundstage will sound (the speaker may measure flat in an anechoic chamber but things like wall proximity and boundaries can affect this in different rooms but thats a subject for a different thread)

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Originally Posted by diyguy (Post 2655109)

Guys, i finally picked up my speakers. This is my configuration for now.
Receiver - Yamaha RX-A810
FS - Yamaha NS-F700
Center - Yamaha NS-C700
Sub - Yamaha NS-SW700

Couldnt afford the Bookshelves for Surrounds and Rear for now. I have a pair of Sony 3-Way Bookshelf speakers, Japanese made. I will probably hook them up for surrounds or maybe Zone 2.

@Diyguy, Congrats on the purchase!! Wish I had that kind of budget :). I remember seeing a Diyguy in HiFiVision forum, are you the one there by any chance? In case you have auditioned the Obsidian, would you mind giving a comparo with your setup, I know both are not in the same league, but still just to get an idea about the differences.

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Originally Posted by UKR (Post 2656888)

UKR, thanks! you wont believe me, but I started with a budget of 30K (stretchable to 60K) to spend on this, and was scouting for demo speakers all along, till I saw this Yamaha series. I almost closed the deal on a demo set of Wharfedales 9.1, 9.2, 9.CS, 9.DFS. The dealer was offering a 30% discount on the list price and I was negotiating for 50% on the used configuration. The reason I had not closed that deal was because he did not have a pair of 9.4 or 9.5 demo pieces and was trying to source it from somewhere else for me.

Unfortunately the Obsidian was not available to demo anywhere in Chennai, so I was unable to check it out and I was reluctant to pull the trigger on it on HiFiMart, without looking at it first hand. I am not on the HiFiVision forum, though I have been reading off it for the past few weeks.

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Originally Posted by condor (Post 2659960)

Guys, any suggestions for a budget all-in-one home theater unit, but without speakers ? Trying to find a unit that can do DVD/CD, USB, FM tuner - and has a 5.1 out-put ?

TIA !

Hi Condor,
Instead of going for a built in AVR + DVD player, I would recommend getting:
A Dedicated Blu-Ray Player (Philips BDP-3000, Sony ) : This gives you more current technology on the players and flexibility on media.
+ Onkyo TX-NR 309 / 509 or Denon 1612 , whichever your budget permits.
This way you will have lot of connectivity options and not worry about future upgrades. The power outputs of these are also significantly high and you can pair any good speakers with them.

The other option is to buy something like : Onkyo HTS-3400
ONKYO SIGHT & SOUND INDIA
and not use the satellites and connect whatever speakers you have and use the Sub!

For all the other HTIBs, I am not too convinced by Sony/ Panasonic/ LG / Samsung!

(PS: Purely my personal opinion expressed here and I have no connection / commercial interests with any of the brands mentioned!)

Regards,
Behemoth

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Originally Posted by diyguy (Post 2659986)

I have a Sony HTIB 5.1 that does all of this, but comes with speakers. Not sure if you will get a new all-in-one without speakers. I had picked it up for ~16K about 3-4 years back...

I have a Sony HTIB connected to the TV, but this HTIB is also not being used much - I could use that instead, and get a DVD player for the TV.

But if I am able to get what I had posted for, I can hope to use the existing speakers (else these will go waste). The player unit is not repairable since Sony says no parts available.

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Originally Posted by Behemoth (Post 2660007)

makse sense.

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The power outputs of these are also significantly high and you can pair any good speakers with them.

Yes - can always buy better speakers later.

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The other option is to buy something like : Onkyo HTS-3400

How would you compare these with the Harmon Kardon HK AVR134 or similar ?

(The reason for checking the budget range is the amount of use I am putting it to these days :( )