Using multichannel analog AND pure direct

[supervij]

Is this a good idea? I know that when using Pure Direct for CDs (using stereo analog), the mains go full range and the subwoofer is disabled. Sounds great, and I love it.

But for SACDs and DVD-As, using the multichannel analog AND Pure Direct, does that send full-range signals to the five speakers and send only the low frequency channel to the sub? I ask cos my centre and surrounds go down to only 60 and 50 Hz, respectively, and I'm not sure it's wise to let those handle full-range signals.

Is it better to NOT engage Pure Direct when listening to SACDs and DVD-As using multichannel analog?

cheers,
supervij

 

[Djizasse]

I know there's a thread around here somewhere that explains this better, but I think that if you're using the multi analog inputs, there's absolutely no processing done, no bass management is applied, that means what comes on the channels, goes out to the respective speakers.

 

[supervij]

Thanks, Djizasse. I'll look for that thread.

cheers,
supervij

 

[Exit]

On my Yamaha receiver Pure Direct cuts the DSP processor out of the sidnal path but it also cuts off the subwoofer. I think it is for playing a full range stereo pair of speakers on the front right and left channels.

 

[supervij]

It cuts off the subwoofer cos the signal being fed is two channel only: left and right. But with multi-channel, it's being fed at least six channels, which includes the LFE. So the sub won't cut out, cos it's still being fed signals. I assume that means that crossovers don't apply and that every speaker is being fed a full-range signal.

I just don't know if feeding my centre and surrounds a full-range signal is wise -- they go as low as 60 and 50 Hz. Maybe I shouldn't engage Pure Direct when I'm in multi-channel analog mode?

cheers,
supervij

 

[Trezl]

Are you afraid that sending too low a signal will hurt your speakers?

My understanding (I could be wrong), is that if a speaker can't do a certain frequency, you just don't hear that frequency. I don't think it actually can hurt the speaker to send it a signal it can't output. That frequency just sort of get's shut off, doesn't it?

 

[billy p]

It cuts off the subwoofer cos the signal being fed is two channel only: left and right. But with multi-channel, it's being fed at least six channels, which includes the LFE. So the sub won't cut out, cos it's still being fed signals. I assume that means that crossovers don't apply and that every speaker is being fed a full-range signal.

I just don't know if feeding my centre and surrounds a full-range signal is wise -- they go as low as 60 and 50 Hz. Maybe I shouldn't engage Pure Direct when I'm in multi-channel analog mode?

cheers,
supervij

Running pure direct would be kind of like running your set up in 5/7 channel stereo, no? Than wouldn't running all your speakers full range as described put more of a burden on the receiver as well?

Just wondering, Bill...

 

[Djizasse]

Speakers have a frequency response and they roll-off at low frequencies. When the signal being sent to the speaker contains frequencies that are in that roll-off area, they simply get attenuated. No harm done.
Just use common sense and set the volume knob to a sensible level. If at higher volumes you notice distortion it's time to bring the volume down.

Pure Direct cuts all audio processing (bass management, YPAO, DSPs), shuts off the video processor and even turns off the display.

Simply put, if you prefer Pure Direct, use it. Even with DVD concerts you have enable PD, it will shut off video, but the sound will still pass.

Djizasse
ps - Yamaha's FAQ

The following image was found in the archives:

 

[Davemcc]

I just don't know if feeding my centre and surrounds a full-range signal is wise -- they go as low as 60 and 50 Hz. Maybe I shouldn't engage Pure Direct when I'm in multi-channel analog mode?

In your SACD player, you should have all the necessary crossover and channel level settings so that bypassing these features in the receiver is a moot point. Your mains and LFE channels will already have been subject to the player's crossover before it got to the receiver, so no channel will be getting a full range signal unless you intended it that way when setting up the player.

Pure direct may be a better choice in that it will also bypass the video circuit, while the m/c input will still display video.

 

[supervij]

billy p, that definitely is not the case. I've been engaging m/c and then PD when listening to SACDs, and I do hear discrete sounds coming from the different speakers, i.e., a guitar in the front left that's not also in the surround left.

Trezl and Tjizasse, thanks for letting me know that it won't hurt my speakers to feed them full range speakers, that's great to know.

But Davemcc, you're right -- I did set all the crossover and channel level stuff in my player. PD in my receiver means that it'll just accept whatever's coming at it, and my player is already applying bass management and re-directing anything less than 80 Hz towards the sub. Okay. Ahhh, many many thanks for that, Dave!

I can now go back to SACD and DVD-A listening and just relax.

cheers,
supervij

 

[billy p]

billy p, that definitely is not the case. I've been engaging m/c and then PD when listening to SACDs, and I do hear discrete sounds coming from the different speakers, i.e., a guitar in the front left that's not also in the surround left.

cheers,
supervij

I was asking a hypothetical question.... I've done my share of experimenting with m/c analog, but if all your speakers were set to large wouldn't that have some effect on the receiver. There is no denying you'll heard a difference with SACD's but if all your speakers are set to receive a full range signal it will have some effect whether the crosssover is at the avr or the player?

Cheers, Bill

 

[Djizasse]

...but if all your speakers were set to large wouldn't that have some effect on the receiver. There is no denying you'll heard a difference with SACD's but if all your speakers are set to receive a full range signal it will have some effect whether the crosssover is at the avr or the player?

Large means no filtering done. If you already made that filtering at the player, the receiver won't have much (if any at all) to "redirect" to them

Don't set both crossovers. It's unnecessary processing. The less the better.

And if your connection from player to receiver is done through multi channel analog, the receiver won't even process any bass management, as receivers normally shut off all processing when operating from these inputs.

 

[billy p]

In hindsight, I guess the OP was asking a hypothetical as well.... I assumed that analog and analog m/c would be equally effected by pure direct mode and sorry for my confusing posts. I know that you and Dave had beforehand answered the question, but my pea brain was thinking something else....

Regards, Bill