How do I play test tones through the sub?

[Brogan]

Stupid question time so apologies in advance...

I've just been playing with some mp3 test tones and an SPL meter.
My aim was to plot the frequency response of the fronts when in Stereo & Direct mode, the sub on its own and then the fronts and sub together.
I should point out that the sub is only ever used for multi channel audio.
Normal stereo music is played through the fronts only.

I've got the tones burnt to CD so I just pop the CD in the DVD player and play each tone back individually.

Doing the L and R fronts was no problem and I get 2 separate plots for Direct mode and Stereo mode (with acoustic calibration applied).

However, how do I get the tones to play through the sub?
The sub is only active when it detects an LFE channel and of course my home made disc doesn't have one of those.

There's probably a setting in the AX5i or 868 which can force output through the sub but I've had a quick look and I can't seem to find anything relevant.

Can anyone help?

[ijd]

The sub is only active when it detects an LFE channel and of course my home made disc doesn't have one of those,
you have already answered your own question, try a google search for lfe tests, there are many, also look for a full frequency sweep, this is the full range from well above what you can hear to well below, it will show up any crossover glitches or any hollow frequncies you may have

[Brogan]

Originally Posted by ijd

try a google search for lfe tests, there are many, also look for a full frequency sweep, this is the full range from well above what you can hear to well below, it will show up any crossover glitches or any hollow frequncies you may have

I already have DVE which has LFE tones and full range sweeps, as well as SigJenny and Room EQ Wizard which are both capable of generating individual tones and sweeps.

What I'm actually after is as I explained in my first post; a way of playing individual tones through the sub.

Anyway, full sweeps aren't much use to me as I am manually recording the values from the SPL meter.
It's a bit hard to do that with a sweep...

[Neil Davidson]

Assuming that it is an amplified sub, you could just plug the DVD player into it via analogue and play the tones.

Use the subs gain control to match the SPLs of the main system.

Neil

Edit - The other alternative that I often use for such things is to use the analogue multichannel inputs on the receiver.

[Brogan]

Originally Posted by ceenhad

Assuming that it is an amplified sub, you could just plug the DVD player into it via analogue and play the tones.

Use the subs gain control to match the SPLs of the main system.

That's an option although it's not something I've ever done before.
It would also mean moving a lot of kit about.

Edit - The other alternative that I often use for such things is to use the analogue multichannel inputs on the receiver.

Hmmm, that may be a better option.
I've already got the left and right multi channel inputs hooked up as this is what i use when listening to CDs in Direct mode.
All I'd have to do is hook up another phono cable for the subwoofer connection.
I may well give that a try.
Thanks.

[Neil Davidson]

Originally Posted by Brogan

Hmmm, that may be a better option.
I've already got the left and right multi channel inputs hooked up as this is what i use when listening to CDs in Direct mode.
All I'd have to do is hook up another phono cable for the subwoofer connection.
I may well give that a try.
Thanks.

If you want to isolate the performance of the speaker then you should use the same output from the DVD and move it between the inputs on the amp.

Neil

[Brogan]

Originally Posted by ceenhad

If you want to isolate the performance of the speaker then you should use the same output from the DVD and move it between the inputs on the amp.

Neil

I hadn't thought of that.
What a great idea.

Thanks again Neil.

[Neil Davidson]

NP! It's my job to know this stuff

[panny300]

brogan can you explain in a little more detail please.which output from the dvd to which inputs on the amp

[Brogan]

Originally Posted by panny300

brogan can you explain in a little more detail please.which output from the dvd to which inputs on the amp

Do you mean how I currently have it set up or how Neil suggested?

Normally I use iLink from DVD to amp for multi-channel audio.
For stereo I use the L & R multi-channel outputs connected to the L & R multi-channel inputs on the amp.

What Neil is suggesting (I think) is to connect from the L (for example) multi-channel output on the DVD to each of the multi-channel inputs on the amp in turn.

[Brainstorm]

Originally Posted by Brogan

I already have DVE which has LFE tones and full range sweeps, as well as SigJenny and Room EQ Wizard which are both capable of generating individual tones and sweeps.

What I'm actually after is as I explained in my first post; a way of playing individual tones through the sub.

Anyway, full sweeps aren't much use to me as I am manually recording the values from the SPL meter.
It's a bit hard to do that with a sweep...

I thank he wants to do this in the exact way as the sound engineer does it in the cinema!?

[Brogan]

Originally Posted by Brainstorm

I thank he wants to do this in the exact way as the sound engineer does it in the cinema!?

It's called a frequency plot and is the normal way of recording the response from the speakers.

I have already done it for the fronts, center and 4 surrounds.
The only problem I have is doing it for the sub due to the nature of the LFE signal.

[Brainstorm]

Set the level on the Pioneer AVR THX ON!

Set the level for the bass manager to (0db) bass manger caution make sure you turn the level down on the subs volume, has the bass manager produces a raw pink noise that would damage the sub bass!

[Brogan]