How low of a Frequency can a dvd player output?

[warnerwh]

I've learned that movies have frequencies below 20hz but do our dvd players actually output those low frequencies? I'm curious because as far as specs go they don't say.

Thank you

[ThomasW]

I don't know what the specs are, but the computer made spectrograms people are posting of DVDs, show content as low as 3Hz

[Chris7]

The low frequency cutoff will be determined by the coupling caps hanging off the DAC or output stage. Wouldn't be unusual to be only 3dB down at 10Hz, even in a low end player.

[jquin]

3Hz? Now that's a serious CAP even for low voltage.
I might be wrong but I thought they were basically DC coupled.
I worked with both a Nakamichi and Harmond Kardon that both worked
well bellow 10Hz with no reduction in voltage so I seriously doubt it's gonna roll off to block DC.
I'll have to check and post again but I dont remember big CAPs on the output.
Hmm I assume you mean the analogue output. SPDIF would probably transmit DC levels and the rest is up to the AMP.

Regards
John Quin

[JonMarsh]

Unfortunately, most mass market consumer CD/DVD players use electrolytic caps in the outputs, and a 50uF 25V cap is not very large or very expensive or very good sounding. Typical CD players have response to 1 Hz or so into a 47 kOhm load.

As Thomas notes, spectrographs of DVDs show strong output down to very low frequencies, there's a lot more below 20 Hz than most of us would expect, which is why ported systems without a very low tuning or a high pass filter can be problematic at times.

Classic examples are U571, and the Pod race in "The Phaontom Menace".

[sprtfan]

I have never thought about this before and may stop me from doing a upgrade I was thinking about. Just to make sure I understand, if I use SPDIF out to a receiver and I'm using the receivers DACs, it will be up to the receiver to determine if there is a cut off or not? I have a HTPC at the moment and use SPDIF to a receiver. So as long as the receiver is good I should be fine?
I was going to upgrade sound cards and run analog out to take advantage of some of the new features of Vista. Some sound cards are supposed to be very good and have high quality DACs in them but they are still limited in size and may have a higher cut off then a stand alone player? I really don't know much about this but would like some feedback on if this makes any since or if I'm way off base and do not need to worry.

[wmilas]

If you use spdif it stays digital the whole way. The DAC's that are used are your pre/pro or receiver. The DAC's in the dvd player are not used and your dvd player is pretty much just acting as a transport (as far as digital audio goes)

[JonP]

If you want to do some checking out of your own equipment, a very cool program called "Spectrogram" has been around for quite a while now:

Early version, fully freeware:

http://www.hitsquad.com/smm/programs/SPECTROGRAM/

Richard Horne's site with current demoware version: (good for 24b 96Khz)

http://www.visualizationsoftware.com/gram.html

Well worth the asking price...