Setup questions [Archive] - Audio & Video Forums

PDA

View Full Version : Setup questions



Krusty
11-23-2004, 03:17 AM
I have owned a low end home theater setup for over 10 years. I just recently purchased a lot of new equipment and need to set it all up. When auditioning equipment I was advised (by the salesmen) to let the company purchase and install everything. I felt that I would get better deals if I shopped myself.

Although it has not arrived yet, I believe that I can do most of what will be required. I recently asked a local high-end stereo shop if they could recommend an installer to just help with a few things. The answer was no and good luck finding someone.

I (and my wife) want the speaker wire to the Surrounds to be hidden. I need to decide between under the carpet or hidden in adhesive channels. Any suggestions?

I also thought I might need an expert's advise regarding speaker and sub placement and other tweaks like crossover settings. Also advise on room treatments.

I was planning on Bi-Amp/B-Wire the two main speakers using the extra two channels on the amp. Then I will have 400 W/C to the mains. How does the Pre/Pro know which channel (1...7) goes to which speaker or speaker half. Do I need to set up each channel and is this difficult?

Is it hard to get just a little help? Maybe better off learning all this myself. It's part of the fun.

I would appreciate any input.

chimera128
11-23-2004, 04:50 AM
You should list the type of equipment that you are getting. That will allow people to give more specific suggestions. I am assuming that you have a 200 wpc amp. Unless you have power hungry speakers there should probably be no reason to biamp the speakers. Most listening is only done at a couple of watts. However if it is still something you wish to try people will probably be able to tell you how to do it once you list the equipment you will be getting. If you can, also list or include a drawing of your rooms dimensions . People will ask for those when recommending room treatments and how to best run the rear speaker wire. I understand the point about learning... I'm building a wall in the backyard that probably would have been done months ago if I hired someone but when it's completed I will have the satisfaction knowing that I created it.

BillB
11-23-2004, 04:55 AM
Keep lurking around forums like this and:

www.AVSForum.com
www.HomeTheaterForum.com
www.HomeTheaterSpot.com
www.HTGuide.com/Forum

Would you happen to have an unfinished basement below the room you plan on putting this home theater in? If so you could drill holes through the floor and run the wiring under there.

Many companies now make speaker wire that is so flat it s said it can be painted to match the wall. You could try running it along the baseboards or under the carpet.

As far as speaker settings go, you'll want to get yourself an analog Radio Shack Sound Level Meter and a copy of Rives Audio Test CD 2. Use your Pre/Pros internal pink noise to set the levels after setting their distance. Run your front L&R speakers set to "LARGE" and see where they roll off in your room. Use that as a starting point for your xover freq for when you have them set to "SMALL".

You'll be using analog interconnects between the channels of your amp and pre/pro. I'm not sure about using the extra two channels to bi-amp. It could work I suppose with some sort of Y adapter cable.

Keep reading and asking questions. Learning how to do all of this will bring you much more enjoyment than having an installer do everything, leaving you no clue how to troubleshoot a problem should one come up.

Good Luck!
Bill

kfalls
11-23-2004, 05:23 AM
You don't mention what gear you have, but if you're stating 200W/ch it's either some very good gear, or we're talking peak wattage. If you have good gear bi-amp isn't really necessary. The argument for bi-amped speakers is to minimize the effects of the woofers xover on the mid/tweeter and to free up power so the mid/tweeter isn't congested.

You also talk about the "two extra channels", which probably means you have a 7.1 system and the extra two channels are the rear surrounds. Some receivers (Yamaha for one) let you reassign the two rear channels. If assignable, you could set them to the AUX input and feed the sub-out to this input, then connect the rear speaker's amp to the woofer section of the mains. If you have seperates, just connect the sub-out to the input of the extra amplifier channels.

Placement is all experimentation. The front channels should be equidistant from the listening position. If the speakers aren't shielded ensure they're far enough away from the TV/display so the magnetic field from the magnets won't affect the picture. Once you've set the levels, you can experiment with toe-in and center speaker tilt to achieve the best imaging. If possible try to keep the mains away from side walls to minimize early reflections so it doesn't smear the sonic image. Rears placement is dependant upon what type surrounds they are (bi-polar, di-polar, direct). Di-poles are usually placed to the sides of the listener above ear level with the listening position in the "null region". Bi-pole are usually above ear level on the rear wall and direct on stands or wall-mounted in the rear.

Krusty
11-23-2004, 02:18 PM
You should list the type of equipment that you are getting. That will allow people to give more specific suggestions. I am assuming that you have a 200 wpc amp. Unless you have power hungry speakers there should probably be no reason to biamp the speakers. Most listening is only done at a couple of watts. However if it is still something you wish to try people will probably be able to tell you how to do it once you list the equipment you will be getting. If you can, also list or include a drawing of your rooms dimensions . People will ask for those when recommending room treatments and how to best run the rear speaker wire. I understand the point about learning... I'm building a wall in the backyard that probably would have been done months ago if I hired someone but when it's completed I will have the satisfaction knowing that I created it.

I thought the equipment was in my signature. Here it is:
B&K Reference 50 Series 2 Pre/Pro
B&K Ref 200.7 S2 Amp
Energy Veritas 2.4i Mains
Energy Veritas 2.0ci Center
Energy Veritas 2.0ri Surrounds
Energy EXLS 12.2 Sub
Denon 955S
Monster HTS 5100SS

Regarding the room dimensions and layout, I will get to that. Thanks!

Krusty
11-23-2004, 02:33 PM
You don't mention what gear you have, but if you're stating 200W/ch it's either some very good gear, or we're talking peak wattage. If you have good gear bi-amp isn't really necessary. The argument for bi-amped speakers is to minimize the effects of the woofers xover on the mid/tweeter and to free up power so the mid/tweeter isn't congested.

You also talk about the "two extra channels", which probably means you have a 7.1 system and the extra two channels are the rear surrounds. Some receivers (Yamaha for one) let you reassign the two rear channels. If assignable, you could set them to the AUX input and feed the sub-out to this input, then connect the rear speaker's amp to the woofer section of the mains. If you have seperates, just connect the sub-out to the input of the extra amplifier channels.

Placement is all experimentation. The front channels should be equidistant from the listening position. If the speakers aren't shielded ensure they're far enough away from the TV/display so the magnetic field from the magnets won't affect the picture. Once you've set the levels, you can experiment with toe-in and center speaker tilt to achieve the best imaging. If possible try to keep the mains away from side walls to minimize early reflections so it doesn't smear the sonic image. Rears placement is dependant upon what type surrounds they are (bi-polar, di-polar, direct). Di-poles are usually placed to the sides of the listener above ear level with the listening position in the "null region". Bi-pole are usually above ear level on the rear wall and direct on stands or wall-mounted in the rear.

Yes, I have seperates finally. Been wanting to upgrade for years. It is a B&K 200.7. If I hook up the rear channel output to the main speaker woofer, how does the Pre/Pro know to send front channel nfo rather than rear channel info? Is the b-amp a waste of wire and time? I already ordered enough wire to do it.

Would I be better off using all 7 channels for true 7.1 sound. I will listen more to movies than music.

Regarding the center channel, is it better to have it under or over the HDTV? I have a 60 inch Sony.

The rear surrounds have the ability to be switched from bipole, dipole or "corner". Which would be better? It is difficult to move them around due to having to mount them and the speaker wire issues.

Thanks.

Krusty
11-23-2004, 02:36 PM
Keep lurking around forums like this and:

www.AVSForum.com
www.HomeTheaterForum.com
www.HomeTheaterSpot.com
www.HTGuide.com/Forum

Would you happen to have an unfinished basement below the room you plan on putting this home theater in? If so you could drill holes through the floor and run the wiring under there.

Many companies now make speaker wire that is so flat it s said it can be painted to match the wall. You could try running it along the baseboards or under the carpet.

As far as speaker settings go, you'll want to get yourself an analog Radio Shack Sound Level Meter and a copy of Rives Audio Test CD 2. Use your Pre/Pros internal pink noise to set the levels after setting their distance. Run your front L&R speakers set to "LARGE" and see where they roll off in your room. Use that as a starting point for your xover freq for when you have them set to "SMALL".

You'll be using analog interconnects between the channels of your amp and pre/pro. I'm not sure about using the extra two channels to bi-amp. It could work I suppose with some sort of Y adapter cable.

Keep reading and asking questions. Learning how to do all of this will bring you much more enjoyment than having an installer do everything, leaving you no clue how to troubleshoot a problem should one come up.

Good Luck!
Bill

Thanks for the links.

I am slowly getting to understand the vocabulary. Please explain the "roll off". I do have a sound meter and can adjust each speaker to be the same. Still confused about how to measure for crossoversettings.

Thanks.

BillB
11-23-2004, 03:45 PM
I am slowly getting to understand the vocabulary. Please explain the "roll off". I do have a sound meter and can adjust each speaker to be the same. Still confused about how to measure for crossoversettings

The first thing you want to do if your pre/pro allows is set the distance or delay setting. This tells your system how far each speaker is from your primary listening position "sweet spot". Preferably the front three speakers should form an arc (rather than along a flat plane) and be an equal distance from the sweetspot.

Next you want to use your pre/pro's internally generated pink noise (like static) and sound level meter to set the levels so that each speaker's output equals at the sweet spot. Make sure you use a decible (dB) level high enough, 70dB-80dB should work fine. You should then set the front L&R to large and the sub to NO or OFF.

Once those are set, insert a test disc (I prefer Rives Audio Test CD2 becuase it includes tone that account for the known errors of RadioShack's analog sound level meter) with 1/3 octave tones. You may want to set up and print out a quick Excel spreadsheet with each frequency listed and a corresponding column for you to write down your results. Place your sound level meter pointing towards the front of the room, preferably at or near your ear level when seated.

Try to use a frequency in the middle, 1kHz is a popular one, and play it adjusting your pre/pro's volume level until your meter reads a solid 80dB. Note that volume #.

As each frequency is played jot down the dB level your meter is reading. If using Excel you can then plug them into a nice ol' line graph. This will help you identify where to start with your crossover point. If using a reference of 80dB @ 1kHz, you're looking for a point in the bass region (below 120Hz) where it is at 77dB (-3) or less and where it doesn't peak below that. For this example we'll say it's at 60Hz.

You'll have already calibrated your sub control's volume level with the pink noise generated by your pre/pro. What we are concerned with now is the crossover and phase. You'll need to go back into your pre/pro and set the SUB to ON or YES.

If using the xover in your pre/pro you'll want to set this at or as close to 60Hz as you can get it. You'll want to turn the xover knob on your sub all the way up or all the way down. Most subs also have an internal xover bypass switch when you use an external xover (like in your pre/pro). This avoids a doubling (cascading) of xovers.

Now that your sub's volume level and xover level is set, we want to target phase. It appears your sub has a variable phase control (knob rather than selector switch). If that is the case we want to set it at ZERO. Play the tones from the frequency above your crossover point (we'd use 80Hz in this example as it's a 1/3 higher than 60Hz) on down to 20Hz. Jot these number down. Turn the phase knob up a tick and repeat. Go through however many "ticks" your sub's phase control has until you reach 180.

Plot all of these number out (preferably in Excel) and you'll be looking for two things: 1) where your sub is equal to your main L&R speakers at the xover point, and 2) the smoothest response. These usually go hand in hand. In our example speaker X was down 3dB to 77dB @ 60Hz. We'll be looking for the phase "tick" where our meter was reading 77dB @ 60Hz from our sub. If several "ticks" resulted at that ideal we want to look for which "tick" resulted in the smoothest response from 80Hz down to 20Hz. This is the "tick" we want to set our sub's phase knob at.

After doing that we want to go back into our pre/pro and set the front L&R to SMALL, SUB=ON or YES. We want to run the frequencies we did for phase again (80Hz down to 20Hz in this example). We want to look at what our system is doing at the xover frequency (60Hz in this case). It should be the same as when we were only measuring the front L&R and had the sub off. Below that frequency we should see improvement, a leveling out as opposed to a downhill slope towards 20Hz.

I'm sorry if this sounds difficult but it's actually easier than it sounds.

Good Luck and nice system!

Bill

kdb16
11-24-2004, 01:19 AM
Bill: Thanks for the very informative write-up. I have just bought a Radio Shack SPL meter, and am waiting for the Rives Test CD 2 to arrive in the mail. In the meantime, I have a question for you:
I finally saved up enough money to add a subwoofer (Infinity PS10) to my current setup (Onkyo 501 + Hsu Ventriloquist).

I hooked up the sub a couple of days ago, and at first I thought I had a defective unit, as no sound would come out of it. After a lot of fiddling, I got it to work, but...

...The Onkyo 501 has a feature where you can generate pink noise to set the volume for each individual speaker, from -12 dB to +12 dB. For every speaker except the sub, the default setting (0 dB) works fine, meaning I can hear the pink noise fine.
For the sub, I had to go all the way to the max (+12 dB) before any noise would come out of it. The volume control on the back of the sub is at the 2 o'clock position (which is about 70%-80% of max). I double-checked all settings (crossover set on receiver at 150 Hz, sub mode "on", "LFE" selected on sub, etc) and think they are all correct.

So my question is: is it normal that the pink noise is barely audible through the sub? I guess if the frequency of the noise is > 150 Hz, that could be one reason... But if that's indeed the case, how would I adjust the sub's volume level?

Thanks in advance.

Krusty
11-24-2004, 02:52 AM
[QUOTE=BillB]The first thing you want to do if your pre/pro allows is set the distance or delay setting. This tells your system how far each speaker is from your primary listening position "sweet spot". Preferably the front three speakers should form an arc (rather than along a flat plane) and be an equal distance from the sweetspot.

Thanks for the detail. After reading it twice, I am starting to understand. I have had a "Video Essentials for Audio/Video" test disk that I have not used in a few years. I think it only has pink noise per channel and some video tweaks. Does the test disk from Rives have a lot more detail? Does it have tests at the various frequencies? You stated to use a frequency in the middle such as 1 kHz and then test the other frequencies. Do you select this from the test disk?

Thanks. Your explanation really helped.

BillB
11-24-2004, 04:44 AM
So my question is: is it normal that the pink noise is barely audible through the sub? I guess if the frequency of the noise is > 150 Hz, that could be one reason... But if that's indeed the case, how would I adjust the sub's volume level?

kdb16,

I recommend starting with your sub's volume knob at the 12 o'clock position. Be sure to go into your Onkyo's Speaker Settings menu and be sure all are set correctly. Set them all back to ZERO and be sure the distances or delays are set correctly. I would then double check your connections to make sure they're solid. I am assuming you're using a line level connection with a digital coax (subwoofer) cable?

Now run through the pink noise again and see what happens. If things are still as far off as they were before the recheck, you may want to find out if your Onkyo allows different Subwoofer levels for different situations. It would be in a menu and could be having an impact on your results.

Your other option is to decrease the other speakers slightly so that you don't have to pump up the sub's level all 12dB.

Let us know how you make out.

Bill

BillB
11-24-2004, 04:52 AM
Thanks for the detail. After reading it twice, I am starting to understand. I have had a "Video Essentials for Audio/Video" test disk that I have not used in a few years. I think it only has pink noise per channel and some video tweaks. Does the test disk from Rives have a lot more detail? Does it have tests at the various frequencies? You stated to use a frequency in the middle such as 1 kHz and then test the other frequencies. Do you select this from the test disk?

Krusty,

I recommend using the internally generated pink noise from your pre/pro as opposed to a disc as it will give you a reference level for all sources (CD, DVD, TV, etc) as opposed to only your DVD player when using a Test DVD.

The Rives Test CD 2 has 70 test tone tracks on it, 35 are "flat" 1/3 octave tones, the other 35 are "corrected" 1/3 octave tones that account for the errors of the ANALOG RadioShack sound level meter. If that is the meter you will be using you want the corrected tones, otherwise use the flat ones with any other meter.

The other thing I like about the Rives disc other than the corrected tones is the fact that it breaks each 1/3 octave tone (frequency) into individual tracks so that you can isolate them (like the 1kHz tone) or put them on repeat to fine tune things with as much ease as possible. Other test CD's like the Stereophile discs use indexing withing a track and it is very cumbersome.

If you PM me with your email address I'll send you a copy of my Excel spreadsheet that I have set up. It may give you a better picture of what I'm talking about in my response.

Bill

kdb16
11-24-2004, 08:28 AM
Bill, thanks for your reply and advice. I'll follow it and let you know how it goes.

BTW, my sub is hooked up to the receiver via a simple 6-ft mono cable with RCA jacks at both ends... Would a coax cable make any difference? Frankly, I am skeptical of all of the advertising hype around Monster Cable and similarly high-priced accessories.

Regards,
Kim

BillB
11-24-2004, 09:29 AM
Kim,

Most "subwoofer" cables are simply a long coax cable like you'd use for a digital connection. Coax is preferred over a "normal" RCA terminated cable because the shielding is generally better which is beneficial in the long runs subwoofer cables usually require. There's less of a chance they'll pick up hum or noise along the way.

Many companies besides Monster Cable make these "subwoofer" cables. I use one by Acoustic Research that I got off of Accessories4less for about $20. It works perfectly.

Bill