What else besides SPL meter for setup? (1 Viewer)

[Mark Hedges]

What else do I need besides an SPL meter to setup my 5.1 system? I want to try to determine the optimum placement/settings for my subwoofer, optimum spacing for my mains, and figure out if I should have my speakers set to "small" or "large". Will the Avia DVD help me with all of this, or should I try something else?

Thanks!

Mark

 

[CurtisSC]

The Avia DVD will help you with everything.

 

[ChadLB]

I beleive there is no DTS setup on the avia. If you want that you will also need the sound & vision disc. If I am wrong let me know.

 

[Phil Iturralde]

...no DTS setup on the avia. If you want that you will also need the sound & vision disc.

You're correct Chad. S&V also has 6.1 test tones - use 85 dB SPL (Weight "C" / Speed = SLOW).

Phil

 

[Mark Hedges]

Would settings for DTS be very different from settings for DD 5.1? I think my reciever only has 1 set of settings - I know I cannot have it automatically change settings when going from DD to DTS.

Mark

 

[ChadLB]

Mark
With my setup the only diff between DD/DTS was to hit 75db for setup in DD my receiver volume was at -25 and for DTS is was at -29. All speakers were same setting so for me it didn't make a difference except for where the volume knob was set when watching a DD vs. DTS movie. I don't have seperate settings for DD/DTS that hold.

 

[Brian L]

To get the sub location and crossover right, you need discrete low frequency test tones.

I have tried and own many different discs. My favorite is from Bass Mekanix (I got mine from Amazon). They have tones in .5 Hz increments from 20 to 99 Hz. In my room, those tones produced the most stable readings on the SPL meter.

With this disc, you can map your frequency response on graph paper (or stick the values in a spread sheet and let Excel graph it for you).

And if/when you do take readings with discrete tones, be prepared for a bit of a shock when you see how ragged the LF response in a typical room is.

BGL

 

[Mark Hedges]

Thanks for the suggestion brian - I think I will try it.

Which brings up another question - at what level of bass does one run the risk of damaging speakers? My current mains are rated down to 60 hz and my center to 70. If I send these speakers 30 hz signals could it damage them?

Mark

 

[Brian L]

Which brings up another question - at what level of bass does one run the risk of damaging speakers? My current mains are rated down to 60 hz and my center to 70. If I send these speakers 30 hz signals could it damage them?

This always kills me....

I don't really think you have much to worry about as far as damage is concerned. I mean, think about what everyone did before the popularity of Home Theater, Subs, Crossovers, Bass Management, etc.

You bought speakers that you liked (that likely did not go much below 50 Hz or so, and that assumes they were well designed and had fairly large woofers), and played recordings that you liked, without much knowledge of how low the bass went.

If you blew something up, it was more than likely because the amp was driven into clipping, and what got toasted was probably the tweeter, not the woofer.

Of course, if you do suffer a Spinal Tap moment, all bets are off

Anyway, while your fear of damage is overwrought, you will still benefit from having your mains crossed over to a powered sub.

I would bet that with your speakers, an 80 to 100 Hz crossover would keep the load off of your mains (mid range is said to improve if a smallish speaker is not also trying to produce low bass), and lets your amp get buy without having to bust its hump trying to deal with low bass.

While 5 truly full range speakers (and the amps to drive them) is the way to go (assuming you have the wallet and room to do it), a sub/sat system, properly set-up and positioned can sound really nice....I would bet most users here are in the sub/sat category.

BGL

 

[Chuck Bogie]

Well, a buddy of mine dropped by over the weekend, and was VERY impressed with the sound quality of my modest setup... And he's spent some major bucks on his stuff, but hasn't bothered with little things like speaker placement or calibration...

 

[Mark Hedges]

How do you orient the spl meter during calibration? Is it best to point the mike at the speaker in question, or should I leave it pointing straight up?

Mark

 

[ChadLB]

The meter should be in the same spot and pointing at the same spot during calibration. I believe the best place to point it is where the ceiling and front wall meet. If you don't have a tripod to put it on I used a table that is about the same height and was able to monitor the meter while calibrating.

 

[Geoff L]

Brian

That particular Bass Mekanik test disc (V5.0) you speak of, I also have. If I have the wrong disc let me know!

What people need to now is that, yes it goes in .5hz increatments BUT!

FROM THE V5.0 BASS MEKANIK DISC INSERT:
Quote:
Tracks 20-99 if used properly can increase your bass spl by 1db.

It Continues:
If the tracks are played on a system that has a stereo sub system, the tone will appear to fade in and out. If played on a mono sub system they will have a constant tone. This is because each channel (Right and Left) contain different frequencies and interfere with each other when played at the same time! For example, track #20 which contains 20hz, ~{actually contains both 20hz and 20.5hz.}~ 20hz is recorded on the left channel and 20.5hz is recorded on the right channel.
Since SPL systems only require a mono signal, we have utilized the extra channel to give you twice the test tones on 1/2 the number of tracks. To determine which channel is the loudest you will first need to connect your sub/s amplifier/s to a "mono signal". If you are not comfortable with this please consult Bass Mekanik.
Next try both channels and try several tracks above and below the track that contains your resonant frequency.
End Quote:

------->
I am sure you are aware of this and I am curious as to how you go about making use it???
------->

I have a number of Bass test discs that I much prefer over this one. Other Mekanik discs, Stryke, (Granite Audio is my favorite by far, though very pricey)
"Had I known" this was the way Bass Mekanik recorded (V5.0), I would have never picked it up on-line months ago. Unless you understand what they are tellng you, it is possibly to damage your regular speaks if your not set small and carefull with the volume knob.
It's not a DVD, it's a stereo music CD till the split channel test tracks.

I feel there are much better bass test disc out there. IMO

Still very curious to how your using it Brian. You must feed one channel and graph then feed the other to the sub and fill in the the rest of the graph?

Regards
Geoff

 

[JohnCRome]

Hi,

just got the AVIA disc....of course I realized it was only NTSC after I'd placed the order...and being in europe we're under PAL so question is...

how can I make the most of it? I have a denon 3802...can I put it to any use or do I keep it as a memento?....and what, if any exist for PAL?

Thanks....

J.

 

[Brian L]

Still very curious to how your using it Brian. You must feed one channel and graph then feed the other to the sub and fill in the the rest of the graph?

Not sure there is any big deal here, and not sure you have any fear of damaging your gear.

Well, perhaps I misunderstood how to use it, but I took the info on the booklet to mean that the left channel had all the whole frequencies, while the right had the 1/2 hz increments. When I EQ'd my sub, I just connected the left channel output of CD player input to the sub for all whole frequencies.

When I needed a 1/2 Hz increment (my EQ has 1/6th Octave bands below 80 hz, so a couple of the frequency centers are 1/2 Hz or very close) I just swapped the output from the CD player.

No fuss, no muss. I measure and chart each frequency that I can adjust.

I actually used a Infinity RABOS SPL meter to EQ the sub. Using the Bass Mekanik disc with the RABOS meter produced the most stable, easy to interpret readings I have ever had.

Of course, there are other test CD's out there. I guess you need to use what makes the most sense for you, but I think the BM CD is a neat piece of software.....assuming I have not been using it incorrectly.

Brian

 

[Geoff L]

Brian

Ok, this is the only way you can make use of it. As I made mention in my last queston & paragraph in my last post.

Used that way it works fine. But if a person was to throw it in their cd-transport and start running test tones you'd get a mess because of the 2 different freqs trying to play threw the sub at the same time.

So yes, the way your using it is the only way to get it to work properly. You have to use the analog outs from the CD player one at a time.
You and I may understand this but the average joe might get very confused as to what the hell is going on if he was just pluged into the single sub out of his receiver and didn't disconnect one of the L or R analog RCA's to the Receiver CD input, or taking the signal straight off the CD-player L & R (one at a time).

Thanks for letting me know that what I thought you might be doing, is what you are! It's all good.....

Cheers
Geoff

Edit:
John forgot about you buddy!!! :b
The Audio portion of the Avia Disc for calibration "should work fine"!
The Video section will not work as I understand it. If I am wrong about the Video part, someone please chime in.

Regards
Geoff