How digital speakers work

[wumply]

Hi:

THE REALLY IMPORTANT QUQESTION I HAVE HERE IS NO. 3, SO IF I'VE GOTTEN TOO DETAILED, PLEASE ANSWER JUST THAT QUESTION.

And if you could refer me to a good source of information, that would be cool!!

My son has digital speakers and digital soundcard but that's as far as he goes. Me being me, I want to know how digital speakers work...how they are different from the analog speakers. Aren't all speakers themselves analog?

So here goes. I don't have digital speakers/headphones.

1. Do you need a digital soundcard for the digital speakers?

2. Are the speakers themselves like ordinary speakers--I mean the 2 little Altec spkrs I have beside my monitor with a woofer down below---speakers purchased in 1995---that is, do digital speakers have a magnet and cones? Or what?

3. If I had a digital soundcard could I still use the speakers AND HEADPHONES I've had since 1995? I ask this question because while my son gets sound over his digital speakers but not over the earphones he's always had. If 'yes', I take it the sound quality would not compete with digital speakers sound?

John

[Conan]

1) Yes you do. The soundcard's purpose is to "process" sound from a digital source and then somewhere along the way convert it back to "analog".

2)There is no difference in speaker construction between "analog" and "digital" speakers. It's mostly a marketing term.

3) I'm not sure about this, I will leave it to my fellow Techzonerz with sound cards to answer this question as I only have my motherboard's sound processing.

[wumply]

So Conan...

First thank for your good response.
But your answer or my confusion leads to this question:

As I understand it any natural sounds in our world are analog; to record them in a computer we sample them 48,100 times a second, converting each sampling into a 1 or a 0, as the computer is a digital device. Now to play them back, they are re-converted back into analog so that the speakers can play them...speakers being analog devices. And I assume that if a computer creates a sound, it is digital to start so it is still converted to analog for us to hear it over a speaker.

So is the term digital speaker something of a misnomer? Or does the term have some validity I am not aware of?

John

[Big Booger]

I am no audio genius, but I think it can be stated like so:

1 you convert audio analog file into digital format. then you play on analog speaker through sound card that converts the sound back to analog...

Coverting the audio into digital once, and the reconverting it back to analog leads to quality loss.

Converting the audio into digital, and then playing on a digital sound card with digital speakers produces better quality because you don't have to convert the second time, thus the sound is cleaner, clearer and richer.

I know whenever I play a trailer from say apple.com, on my computer with analog video, the image is wretched looking with lots of macros, artifacts etc.. even in windowed mode.

But when I play it through my digital output into my television that has a digital input, it looks sweet.. even in full screen..
I guess that would be the same way with audio.

I don't know really and I am anxious to see someone post something definitive on here about this topic as it is really interesting.

[wumply]

So BB:

Read your answer. Fascinating. It would appear then that digital speakers ARE somehow of different design and presumably would not play analog sound or not play it well. I wonder: HOW are they different, if they are?

Do you think this is the case?

Do you have any references re this entire topic? Do you have much hope that someone will pick up this thread? Because I am as curious as you.

I searched Texas Instruments and Creative sites and Google, but I didn't find much.

John

[Big Booger]

I did a little research.

First more on digital versus analog technology in general:
http://www.virtualpbx.com/ana_vs_dig.html

Great read, really explains a lot.

Another article, below, explaining the difference between digital and analog:
http://www.howstuffworks.com/analog-digital.htm

I think the basic difference between analog and digital speakers is the technology employed,

From the TI site:
The first is the digital audio pulse-width-modulation (PWM) processor, which employs advanced digital signal processing and fourth order noise-shaping to convert the digital data from the source into the PWM format. The second stage is the digital amplifier power stage, which applies the digital PWM signal directly to the speakers, maintaining a complete digital path from the source to ear.

I don't think analog speakers contain the PWN pulse width modulation processor.. Also I think the amplifiers are different as well. As for the tweaters, woofers, coils etc... I am not sure if they are actually the same, but I am still looking.

I would think that the speaker hardware would remain the same, other than the input and output and how it is transcribed over the different hardware.
Not too sure.

I hope someone can help out in this.
:D

Finally found something on how the sound is produced in the digital speaker:
http://focus.ti.com/docs/apps/catalog/resources/blockdiagram.jhtml?appId=1&bdId=348

Have a look. The main difference would be that the input of the digital signal goes straight into the speaker, whereas with the analog, it has to be converted first, along with some signal conditioning...

[wumply]

I willl have a look, BB, and I thank you for doing that research and for the information you've given me.

John

[Conan]

Let me say it again there is no difference between Digital and Analog speakers. I have a full-blown Home Theater set-up in my room and there is nothing in my JBL Studio Series speakers (http://www.jbl.com/home/products/product_detail.asp?ProdId=S26II&SerId=STU&sCatId=) that would differentiate it from any other normal speaker, except for the build quality of JBL.


I think the basic difference between analog and digital speakers is the technology employed,

From the TI site:
The first is the digital audio pulse-width-modulation (PWM) processor, which employs advanced digital signal processing and fourth order noise-shaping to convert the digital data from the source into the PWM format. The second stage is the digital amplifier power stage, which applies the digital PWM signal directly to the speakers, maintaining a complete digital path from the source to ear.

I don't think analog speakers contain the PWN pulse width modulation processor.. Also I think the amplifiers are different as well. As for the tweaters, woofers, coils etc... I am not sure if they are actually the same, but I am still looking.

I would think that the speaker hardware would remain the same, other than the input and output and how it is transcribed over the different hardware.
Not too sure.


That is all contained in the digital processor or digital amplifier. Speakers are only capable of accepting "Speaker Cables" which by no means are digital in nature.

For example, I have a Digital DVD Player connected to my Dolby Digital/DTS Amplifier by means of an Optical Digital Cable, hence the digital links are continuous from the DVD Player to the Digital Amplifier. Now from the Amplifier to the speaker, it's just normal speaker cable (of course the proper thickness shoud be observed) and there is no other decoder within my speaker's cabinet.

[FastGame]

Conan is right, all speakers are analog. The digital speakers that are used with computers contain the DAC's ( Digital to Analog converters) with the AMP and use those instead of the DAC's on the sound card, other than that the signal is analog by the time it reaches the speakers.

[Big Booger]

Ok,
You may be right but from reading the TI site:


I , maintaining a complete digital path from the source to ear.

how could it maintain a complete digital path, from source to ear, while using an analog speaker?

From what you say and what they write, it doesn't make sense... care to clarify that?

i may also be mistaken, but conan where in that JBL article does it mention that those speakers you linked to are digital speakers?
Just need clarification in this matter becuase it seems to me that they wouldn't label a speaker digital unless it was distinguishable from analog speakers...
I mean is it just a label? If so that is a crock of shit.

[FastGame]

Originally posted by Big Booger
Ok,
You may be right but from reading the TI site:
quote:, maintaining a complete digital path from the source to ear.

how could it maintain a complete digital path, from source to ear, while using an analog speaker?

From what you say and what they write, it doesn't make sense... care to clarify that?
Well that statement in it's self (from source to ear) is crock...from spearker to ear is a thing called space :) what crosses that space is a sound wave prue & simple unless these speakers come with a coax or fiber optic cable that plugs into your ear....

Anyway thats me...can someone provide a link to some 100% all digital speakers ? the signal may be digital all the way to the speakers, I want too see if they never convert over to analog....

[lynchknot]

FG is correct - Digital signals are converted to analog before it reaches the speakers. It is possible (if the speakers are powered) to have a digital cable to the speaker (therefore "digital speaker"), which will then be converted and amplified within the speaker cabinet - sent as analog to the speaker terminals.
as far as I know, a digital signal does not have the electrical current to provide amplitude for the speakers.

Of course, i've been out of the audio scene for a while now - this is confusing -

The digital revolution is taking over the audio world. Analog speakers can't reproduce true audio with the clarity and power of digital speakers. With digital speakers, you can have movie-theater sound quality at home and on your PC. TI has turned passive analog speakers into rich, high fidelity and interactive speakers. With the introduction of its first four devices, TI provides speaker manufacturers and PC original equipment manufacturers (OEMs) with the industry's first complete digital speaker solution that addresses all of the audio subsystem needs. By using TI's digital signal processor (DSP) technology, audio speakers will produce a crisper, clearer and richer sound than analog speakers - allowing PC users and PC gaming enthusiasts to enjoy a superior audio experience. This technology also enables new audio applications in the commercial and the business place by improving the quality of internet conferencing/chat and speech recognition. Come see what all the noise is about.

[Dehcbad25]

Well for all SB Live 5.1 to up owners this can be a bit more clear. In the conectors there is a Digital conection. Just to clarify, the Speakers are analog :p but the conection itself is digital. Some speakers like the Digital BA7500 from Boston Acustic looks like a standard four-channel array of speakers plus a subwoofer; the Boston set, however, uses digital coaxial input (a primary connection type for digital components) to create a virtual central channel of sound from the front pair of speakers
Now, this set is a bit expensive, and a 5.1 seems better choice, since the final price is the same :p
to add a litle more, I search in How Stuff Works, and I couldn't quite find exactly "Digital Speakers" but I found THIS (http://electronics.howstuffworks.com/question713.htm) about the flat speakers (maybe this are the Digital Speakers)
Basically, by theory, almost everything here is right. Sound Stored in the HD si digital (bits) but the speakers are analog. When talking about digital speakers it is the conection.
Hope this helps a little bit, since all this is getting kind of confusing :confused:

[lynchknot]

So yeah, powered speakers that handle the conversion within the cabinet.........

[Big Booger]

So to sum it up, the conversion of the signal for a digitally connected sound system happens in the speaker rather than in the card?

And an analog sound system, the conversion happens in the card rather than the speaker?

If that is true then I kind of understand this... if not this is utterly confusing...

And the difference between an analog speaker and a digital speaker is basically the inputs?

[phishhead]

then why does my card have a digital output and analog out put for speakers? this whole thread has got me utterly confused.

[lynchknot]

My guess is it's for a powered speaker system, such as a subwoofer - where you can run a digital line to it.

[Conan]

Well, the reason I used my JBL speakers for an example was because there is no way in hell that any PC setup is going to be better than having a full blown Home Theater set-up with a Big Screen TV, DVD Player, powerful Amplifier and Home Theater Speakers. Also, for simplicity, all components of the Home Theater can be readily seen, unlike the shrunken nature of a PC setup.

If we are talking about Digital Sound isn't it the movie theater that started this and not the PC right? So the Home Theater setup is really a "Scaling Down" of the Audio-Video experience we get from the movies to be brought into our living room/bedroom.

Now, you say that your Sound Cards have digital out ,but then there is always a decoder to convert digital signals back to analog. If it was digital from end to end, we would be hearing 1's and 0's (no offense zErO :D)! Maybe the amplifier/decoder is built into the PC speakers for lack of space rather than having a visible "external" amp that would take up valuable space, hence they used the term "Digital Speakers".

But in the end all speakers are analog.

Edit: upon seeing Lynch's post about Sub-woofers, I have a 10 inch Sub for my room, and that's analog too. The amp/decoder components in a PC setup are probably buit into the Sub since that is where the available space is.

[lynchknot]

Originally posted by Big Booger
So to sum it up, the conversion of the signal for a digitally connected sound system happens in the speaker rather than in the card?

And an analog sound system, the conversion happens in the card rather than the speaker?

If that is true then I kind of understand this... if not this is utterly confusing...

And the difference between an analog speaker and a digital speaker is basically the inputs?

A digital signal needs to be converted to electrical current to move the speaker cone. It is put through a digital sound processor and converted to analog so that the signal can be amplified. This is inline of the signal path. The signal can leave your computer as as a digital signal or as an amplified analog signal (depending on where the digital to analog converter is - somewhere along the line it needs to be converted before it reaches the speaker itself (not the speaker cabinet) but the speaker terminals.

One advantage of a digital signal is it won't pick up any radio frequency noise as an analog wire can - especially with long runs and it will suffer no loss of information. Once it reaches the speaker box, it can then be converted to analog and amplified -

[Big Booger]

I will stick with analog speakers.. sound has never been my forte anyway..

hehehe

[wumply]

It occurs to me to wonder at this point if anyone knows of an engineer who works for a company that designs and makes speakers or has a friend or contact who might know of such an individual. It may be a long shot but it might lead to a conclusive answer too. There seems to be considerable difference of opinion on the answer.

John

[Big Booger]

Great topic starter. I tend to believe these guys about the actual sound once it exits the speaker has been converted to analog at some point. I guess the main point is does changing the sound at different places create performance advantages or disadvantages for that fact?

From what I read, I can see how easy it is for a consumer to be mislead. You have to really pay attention and do your homework.

[lynchknot]

Here is an interesting read - new technology - doesn't say how it moves the voice coil though.

http://www.ti.com/corp/docs/press/company/2000/c00013.shtml

**edit - ok, according to the company, it is still analog at the speaker terminals

The TAS5000 is an innovative, cost-effective, high-performance 24-bit stereo digital modulator based on Equibit
technology. This product converts input PCM serial digital audio data to an output PWM audio data stream. The
TAS5000 is designed to be connected to two TAS5100 mono true digital amplifiers for driving loudspeakers. This
all-digital audio system contains only two analog components in the signal chain-an L-C low-pass filter at the
speaker terminals. It can provide up to 90 dB SNR at the speaker terminals.t

[Conan]

Originally posted by wumply
It occurs to me to wonder at this point if anyone knows of an engineer who works for a company that designs and makes speakers or has a friend or contact who might know of such an individual. It may be a long shot but it might lead to a conclusive answer too. There seems to be considerable difference of opinion on the answer.

John

No engineer needed, just trust the Audiophiles around here: FastGame and me!:thumbup:

By the way how come Egghead hasn't replied to this topic, he's also got a monster sound system at home!

[wumply]

Pretty cool panache there, Conan! I only had a vague sense of the meaning of 'panache' so I had to look it up. But my sense was right! It means (Websters) "dashing elegance of manner, carefree spirited self-confidence.

John

[FastGame]

Originally posted by Conan
By the way how come Egghead hasn't replied to this topic, he's also got a monster sound system at home!
Thats a good question..where is that egghead ??

Oh egghead....

[wumply]

I've now read and studied all the answers to my question...have learned a lot--feel I can converse with confidence on the question...my real thanks to everyone's input. Clearly the conclusion is that the speaker still has to get an analog input when all is said and done.

John

[FastGame]

I was watching Tech Tv the other nite and the owner of a large Home Theater, HDTV, Stereo site was on discussing HDTV. I went and posted a Digital speaker question....It seems that Conan is correct...except that there *may* be 1 or 2 super high end speakers that are 100% digital all the way through the crossovers then go though digital amp's before being converted....

Check out the Digital speaker thread (http://www.hometheaterforum.com/htforum/showthread.php?s=&threadid=128619)

[Conan]

300db per octave crossovers? Way overkill, why would you need to go over 24db? Those are for really Esoteric (or crazy) audiophiles!:D

[Big Booger]

I am vindicated! ;D

[FastGame]

Originally posted by Big Booger
I am vindicated! ;D
You may get un-vindicated.....Meridian Speakers (http://www.meridian-audio.com/p_d8k.htm), these dam things have *5* 100watt amps per speaker...LOL

Originally posted by Conan
300db per octave crossovers? Way overkill, why would you need to go over 24db? Those are for really Esoteric (or crazy) audiophiles!:D

True...if some of those peep's have the audio systems they claim they have, you & I have boom boxes...lol

[Big Booger]

seen em before.
I actually came to that site during my research.

I am not an audiophile... if it is too pricey I say screw em. hehehe

[FastGame]

Those speakers also have DAC's

Originally posted by Big Booger
I am not an audiophile... if it is too pricey I say screw em. hehehe

Well I think it would be fair too say that people with our income level....there's no such thing as digital speakers..hehe ;)

Hope I hit the Lotto tonite

[Conan]

Originally posted by Big Booger
I am vindicated! ;D

Even if the signal is Digital at the Crossover, it's still Analog when it hits the voice coils of the speakers (only electrical current will move voice coils).

Those Meridians just have the amps and Digital Signal Processors located within the speaker, to keep it out of site. Like I said before, all speakers are Analog.:msncool:


Those speakers also have DAC's


DAC's means: Digital to Analog Converters. It's always Analog at the end point of the signal.;)

[Reverend]

I think Conan is trying to tell us "All speakers are analog" :D :D

[Big Booger]

Bravo Conan,
You are the definitive source of speaker knowledge.

[lynchknot]

I guess no one has been reading my posts - :(

A digital signal needs to be converted to electrical current to move the speaker cone. It is put through a digital sound processor and converted to analog so that the signal can be amplified. This is inline of the signal path. The signal can leave your computer as as a digital signal or as an amplified analog signal (depending on where the digital to analog converter is - somewhere along the line it needs to be converted before it reaches the speaker itself (not the speaker cabinet) but the speaker terminals.

I agree, a 24db per octave crossover is all that is necessary - I usually have a low crossover point of 70hz in my car w/ 1250 watts running 4 12" woofers - but it was all stolen except the cd player. :(

[wumply]

Contrary to what Reverend noted, I don't think Conan was just telling us all speakers are analog! I think he succeeded!!!

John

[Conan]

Originally posted by lynchknot
I guess no one has been reading my posts - :(



I agree, a 24db per octave crossover is all that is necessary - I usually have a low crossover point of 70hz in my car w/ 1250 watts running 4 12" woofers - but it was all stolen except the cd player. :(

I used to be heavy into Auto Sound too in the past Lynch. My former car had $ 5,000 worth of audio equipment. But those really made the car heavy with the subs and all the wood enclosures, this time with my current car I just concentrated on Speed!:cool:

[lynchknot]

hehe - cool Conan - I was an installer at Elite autosound for a while many years ago. I drive a suburban so I have plenty of room. Unfortunately someone else has my system now. - :mad: :( :(

I was involved in autosound when 1 farad capacitors just came out and were not popular yet - everyone laughed at me for running them - now every competitor uses them!

[Dehcbad25]

Alright!!!!!!!!!!!!
Lynch. I just got an radio alarm for my car, with the starter. Could you come and install it :p I know nothing about cars, execpt how to drive them like there is no tomorrow :D
Ohh, by the way. I found a system similar to yours....and what a coincidence, it was in a suburban too:D :D
So all speakers are ANALOG?? Great.
I always use headphones, so I wouldn't even noticed it:p

[lynchknot]

Hehe - sure Dehcbad25, If you don't mind picking up the airfare and meals, i'd be happy to. What do you mean "radio alarm". Is it a radio frequency alarm - (pager alarm) - with a starter kill?

[Conan]

Originally posted by lynchknot
hehe - cool Conan - I was an installer at Elite autosound for a while many years ago. I drive a suburban so I have plenty of room. Unfortunately someone else has my system now. - :mad: :( :(

I was involved in autosound when 1 farad capacitors just came out and were not popular yet - everyone laughed at me for running them - now every competitor uses them!

I had those 1 Farad capacitors too, they kept my headlights nice and bright when I was blasting my system!:cool:

[lynchknot]

Originally posted by Conan
I had those 1 Farad capacitors too, they kept my headlights nice and bright when I was blasting my system!:cool:

hehe - i'm sure you know they are not for your headlights!! - :eek: - but rather improve transient response.

[Conan]

Originally posted by lynchknot
hehe - i'm sure you know they are not for your headlights!! - :eek: - but rather improve transient response.

Yup, I know but that was one of the "side effects" that I noticed upon installing the Capacitor. My headlights used to flicker along with the bass notes before I added the cap.

[egghead]

This thread has really grown!!!

i have my 5.1 speaker system for my computer

it accepts both analog and digital connections and has a dolby digital decoder built in.
i have digital and analog hooked up

if i select digital only through xp i only hear 2 channels,i have settings on the external amp to upsource the signal to 5.1 emulation

if i select anolog i hear 4 speakers. i can get 5.1 with the special cable from creative labs but its just an analog din plug for all 6 speakers for convenience.

if i play my dvd's thru digital only i get true 5.1 audio.
this is an ac3 dolby digital stream. all speakers work indepenantly.
the connection is 1 rca plug

my soundcard audigy2 platinum ex is not capable to encode or a dolby digital ac3 stream in real time.


only the nforce2 boards can do this. and this is a true digital stream.

my audigy is 6.1 analog and the dvd audio streams will disable digital audio because of the copyright protection creative has installed on my system. this is also a digital stream but has been disabled.

My audigy2 has an optical in and out and this is also a true digital stream using an external dvd player.

i don/t have hiss using any connections but the 5.1 true digital stream is what you wan't

i don't have a clue what this info will mean to you but i will post it to give you an idea of my setup


cheers
egghead

[Dehcbad25]

with Radio Alarm I mean the control remote works in a readio frequency, and it will activate or deactivate by proximity. So if I get closer to the car, the alarm deactivates, and if I go away, it activates and locks all the doors, without me touching a button.
The starter what it does, is that if I press the green button on my alarm it will start my car :D Really nice since here is very cold in winter.
Instead of your airfare and ticket, I will drive all the way to there.
Some vacations would be great, and I like driving around. Plus you need to have your tools at hand:p

[lynchknot]

hehe - the 'ol proximity alarm. Is there a back-up button - just in case?
I remember the old Viper alarm "protected by Viper, please stand back" - kids would like to set it off for the fun of it and you can't really use it in parking lots.

[Dehcbad25]

Sorry lynch. You were using bad one :p
That is not the problem of the proximity alarm, since it is the settings of the detection (like noise level) I used to work on alamrs. The real problem of the proximity alarm is the jamming of the frequency, but this one that I got it has really well programmed the frequency.
And yes, it has a button to deactivate it or activate it.
I am talking about top class alarm:D
Want the brand??? :spam2:

[egghead]

????????????///

have I been away???????????????