Dolby Enablement, really what is it and how does it work?

fayeanddavid

Distinguished Member
I've read a lot about Dolby Enabled Speakers (upward firing normally located on your L&R and Surrounds as it works) but what is it........?
Read about specific crossovers required within the speakers according to Dolby and they licence accordingly (the cynic in me says "revenue stream",)
Therefore the AVR will also need to support this dictat (more revenue stream) to match the speakers.

So my questions are;
  • What is Dolby Enablement?
  • How and why does it work in terms of diffuse reflections?
  • What design in terms of FR, I read designed dips around 7kHz and lifts around 12kHz (or it could be the other way around)?
  • Speakers used that are not Dolby Enabled would/could suffer how if used as up firing if Dolby Enabled is selected?

Lastly what also happens (design/frequency wise) when other options are chosen (on/in ceiling) as regard AVr output and speakers, and is this a large does of mumbo jumbo or are their palpable differences between all three (audible that is and not fluffy cloud stuff)?

Don't get me wrong, I like the Atmos/DTS X concept and I am enjoying DSU and Neural X, just very curious and slightly bewildered

Thanks for reading
 

fayeanddavid

Distinguished Member
No one???

All I'm looking for is the engineering (sound) difference between the three modes and why

Pretty please
 

fayeanddavid

Distinguished Member
My own very coarse assessment yesterday, after a couple of glasses of Macon was as follows.

I stood between the front Right M6 with S2 mounted directly above and the tv and centre M6, about half a metre out from the wall so that I could here the upfiring S2 and still have the ambience of the FR and Centre
I was watching/listening to the ICC cricket and in particular the crowd noise and applause with DSU enabled

Results:
  1. Front Height option; full range (it seemed) from the S2, bigger sound is what I would say this is
  2. In ceiling option: not as full some as above, center seemed some what muted (thicker) with this option
  3. Dolby Enabled; compared to the other two tests did seem lighter and airy and more atmospheric (that word) than the other two on test......

Next test, maybe Wednesday, will be from MLP, and will do a similar test

Initially this does indicate a shift in Frequency Response and possibly shaping in each instance, any one else out there who can add to this or am I the only sad person out there who cares.:(:(
 

ashenfie

Well-known Member
No one???

All I'm looking for is the engineering (sound) difference between the three modes and why

Pretty please

Dolby Enablement seams very odd in a world of digital, that Dolby decided to put a tweak in the analog crossover of the Atmos speakers. As you say the it's a dip and spike in response, but virtually non audible.

Why they did this when it could easily and better done in the digital spectrum is beyond me. It so small it's hardly worth worrying about.
 

fayeanddavid

Distinguished Member
Does anyone know the above at all, thinking @richardsim7 and @Jag @ Epic Home Cinema plus others to chip in
I can't be the only one who has questioned this, be very interesting to see/understand what Dolby have done and why.
And lastly, I guess DTS X uses a different codec for theirs which seemingly doesn't rely on different placement programmes

Thanks
 

fayeanddavid

Distinguished Member
Yes, no jumping to conclusions as yet, I will read later, but if this is what I have read before then Audioholics seem to be quite disparaging in terms of technology and licencing (revenue stream), howver the one statement that sticks in my mind is using a crossover of around 150Hz fro upfiring speakers

I will give the article some more time later today

The burning question still is why and what for is Dolby Enablement?

Thanks
 

ashenfie

Well-known Member
Audioholics are quite outspoken on this subject and I tend to agree with what they are saying.

In an ideal world would you really want crossover in the first place?
 

camelot1971

Well-known Member
They do try and answer that question in the article. I do like their technical reviews, even though a lot is over my head!
 

fayeanddavid

Distinguished Member
Audioholics are quite outspoken on this subject and I tend to agree with what they are saying.

In an ideal world would you really want crossover in the first place?
Just had a considered speed read (part of the Dolby patent also) which indicates to me:
Mid/high frequencies to the upfiring, say 150Hz and up via Dolby Enablement (via the AVR selection)
The remainder to the main speaker/sub as required.
This quote;
The system of claim 10 wherein the audio signal comprises a full bandwidth signal, the system further comprising a crossover coupled to the speaker, the crossover having a low- pass section configured to transmit low frequency signals below a threshold frequency to the front-firing driver, and a high-pass section configured to transmit high frequency signals above the threshold frequency to the upward firing driver.
is the intriguing one as no values are given
I think I understand the boost and cut at 7 and 12kHz respectively and is designed to "trick" the aural perception (although there is the argument within the Audioholics piece that this isn't necessary)
The article suggests that the speaker manufacture cannot comply with Dolby of +5dB at 7kHz and -12dB at 12kHz, but rather a 6dB control rather than the required 19dB swing, makes me wonder how Dolby can specify and also how they can charge for licencing

All that above beside, I note also that 150Hz seems to be the crossover to a Dolby Enabled speaker so that would suggest to me a 140 - 160Hz bass management crossover at the avr for the relevant speaker, do you think that would hold for Height speakers also (not in ceiling)?

Thanks
 
Last edited:

ashenfie

Well-known Member
Just had a considered speed read (part of the Dolby patent also) which indicates to me:
Mid/high frequencies to the upfiring, say 150Hz and up via Dolby Enablement (via the AVR selection)
The remainder to the main speaker/sub as required.
This quote;
The system of claim 10 wherein the audio signal comprises a full bandwidth signal, the system further comprising a crossover coupled to the speaker, the crossover having a low- pass section configured to transmit low frequency signals below a threshold frequency to the front-firing driver, and a high-pass section configured to transmit high frequency signals above the threshold frequency to the upward firing driver.
is the intriguing one as no values are given
I think I understand the boost and cut at 7 and 12kHz respectively and is designed to "trick" the aural perception (although there is the argument within the Audioholics piece that this isn't necessary)
The article suggests that the speaker manufacture cannot comply with Dolby of +5dB at 7kHz and -12dB at 12kHz, but rather a 6dB control rather than the required 19dB swing, makes me wonder how Dolby can specify and also how they can charge for licencing

All that above beside, I note also that 150Hz seems to be the crossover to a Dolby Enabled speaker so that would suggest to me a 140 - 160Hz bass management crossover at the avr for the relevant speaker, do you think that would hold for Height speakers also (not in ceiling)?

Thanks
I see no issue with the licensing, but I would if the patent would stand up to a chalange seams to be on very thin ice.
 

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