Philips SBC HD 1500 wireless DH manual

[Eric F]

http://www.p4c.philips.com/files/s/s...00_dfu_eng.pdf

RF, not IR.

Interesting stuff here. No optical input, which seems a fairly large oversight.

[aschj]

The base station has an analogue stereo input as well as a digital electrical coaxial S/PDIF input.The digital input allows you to enjoy your favourite DVD movies in full surround sound through Dolby Pro Logic II, Dolby Digital or DTS. And the analogue input brings your collection of VCR tapes back to life in full Dolby Pro Logic II surround sound.

Yeah, only coax. Kinda strange imo.

Dammit, I've been waiting for this damn product since it was announced, and this small glitch renders it useless. Unless there exists some Optical->Coaxial SPDIF converter.

[Eric F]

My receiver only has optical tape output/pass-through so the Philips is pretty useless to me as well. Most receivers only have optical tape/MD output.

On top of that these are RF phones! I think these are a wash. The Pioneers are looking good to me now.

[bootman]

Originally posted by Eric F
My receiver only has optical tape output/pass-through so the Philips is pretty useless to me as well. Most receivers only have optical tape/MD output.

On top of that these are RF phones! I think these are a wash. The Pioneers are looking good to me now.

RF would be better than IF in situations where line of sight with the transmitter would not be possible.
For example: You could take the unit and place it in a cabinet and still have the can work.
This would be impossible with IF cans.

[Eric F]

RF is much more susceptible to inteference, especially in an apt. type environment. I commonly get all sorts of inteference from my neighbors already.

[Music Fanatic]

If I understand this part of the manual correctly (note the poor grammar in it!), it means that the system uses compression

Dynamic bit allocation
The digital signal processing makes use of a Philips patented technology that analyses the audio signal and allocates more bits to that specific part of the audio signal's frequency spectrum, which contains most of the information. This results in a significantly more detailed audio reproduction.

[Eric F]

The Automatic Audio Signal Routing (AASR) feature of the HD 1500
basestation allows for audio sources to be connected to its audio inputs and
at the same time it can pass those same audio signals on to – for example –
your Home Cinema receiver.

Stupid Philips- the pass-thru is backwards!

[jaso]

Music Fanatic,

My grammar and spelling is even worse compared to Philips, sorry for that.

From what I understand, compression isn´t that much of a worry in the DD and DTS case. That signal will be compressed anyhow because of Dolby Headphone. 6 channels goes into 2... same would apply for the Pioneer-cups. So I guess that what’s most important is that Philips has done a great job with the Dolby Headphone/Dynamic bit allocation combination.

Compression is not that funny when playing PCM-stereo audio, like CDs. It would be very nice to have some numbers on the bandwidth of Pioneers and Philips units.

Eric,

How could a pass-thru be backwards? :-)

/jaso

[Eric F]

As I stated in my earlier post- since this unit does not have Optical input (like all other standard amps) there is no way for me to hook up my receiver/switcher.

What I meant by the pass-thru being backwards is that essentially it's useless on this unit because I can only hook up one digital device to it.

I really don't understand the logic to excluding an optical input. Most receivers have Optical tape output only. I suppose if I really want to use this unit I will have to purchase a Optical-Coax converter. Add $50+ more. I don't think I'll bother.

[jaso]

Okey, I agree with you about the missing toslink-input.

Speaking of toslink->coax konverter. Here in Sweden (the most expensiv country in the world?) you could get one of those for $25.



Guess I´ll buy some of those :-).

/jaso

[Music Fanatic]

Originally posted by jaso
It would be very nice to have some numbers on the bandwidth of Pioneers and Philips units.

I was under the impression that Pioneers did not use any compression at all. At least that is what some of the Japanese media pages reported.

I'm not sure I agree with you about compression for Dolby Digital and DTS. Compressing a uncompressed signal with a different compression algorithm often produces bad results, like making a photocopy of a photocopy.

[jaso]

Music Fanatic,

Yes, I guess you´re right about the Pioneer´s. But still, a DTS signal does get uncompressed in the amplifier, then compressed again by the Dolby Headphone algorithm. What I was trying to say was that both the Pioneer and the HD1500 will compress the signal a second time, though the HD1500 might do a little more compression. So it will depend on how much higher Pioneer´s datarate is and how good Philips algorithm is, among other things.

Please, correct me if I´m wrong .

/jaso

[Music Fanatic]

Originally posted by jaso
Music Fanatic,

Yes, I guess you´re right about the Pioneer´s. But still, a DTS signal does get uncompressed in the amplifier, then compressed again by the Dolby Headphone algorithm.

The algorithm is proprietary, so I don't know what it does, but I was not under the impression it was in anyway a compression algorithm. I thought instead it applied a transformation to the signal (adding delay, echo, combining signals, etc.)

[jaso]

Sorry, compression was the wrong word. It would be very fun to know how it works. I beleive that it takes, for exampel, the DTS 6 channel stream, and uncompresses it. Then transforming this signal (as you write: daley, echo etc.). I don´t think that the DH algorithm can work directly on a compressed signal. So this uncompressed DTS signal is quite large I guess. After the transformation is done by DH, the signal must in some way get down to at least "PCM-size" (1,5mbit/s, I think the Pioneers can transfer uncompressed "PCM").. This is what I called compression, but I think it isn´t the right word. However, alot of the sound information is trown away here. And the Philips might have to throw away more information. But they both does. It´s, IMHO, impossible that the DH keep all sound info from the DTS signal and sends it to the headphones... the signal would be too large.

Disclamer: I´m guessing!

/jaso

[Eric F]

DTS decodes to 20bits.