DiyMobileAudio.com Car Stereo Forum banner
1 - 20 of 28 Posts

·
Registered
Joined
·
31 Posts
Discussion Starter · #1 ·
Got a question for the dsp gurus? Is there chance that a spdif/toslink spliter could be used and 2 dsp's be used say one for all the right side and one for all the left side of a vehicle and possibly used for surround sound? Just a thought just didn't know if it has been talked about or brought up. I haven't heard or seen it be brought up so thanks for any input possible!!!
 

·
Registered
Joined
·
602 Posts
Sure it would work.... if the DSP's have the correct input&outputs needed.

You can do surround sound with just 1 Helix DSP. They have differential capabilities, and surround sound settings....
 

·
Registered
Joined
·
31 Posts
Discussion Starter · #3 ·
Sure it would work.... if the DSP's have the correct input&outputs needed.

You can do surround sound with just 1 Helix DSP. They have differential capabilities, and surround sound settings....
Thanks for the reply! So if I were to say have a head unit that has 1 toslink/spdif output and split to go to 2 dsp could I just assign the channels in the the dsp and have it work that way or how would I go about doing that? I have an idea but just want some input please.
 

·
Registered
Joined
·
602 Posts
So if I were to say have a head unit that has 1 toslink/spdif output and split to go to 2 dsp could I just assign the channels in the the dsp and have it work
Think you already have the answer. I have no experience in what your are trying, but on a pure technical basis, where you supply an input, assign outputs, you will have sound coming out of the speakers.. As far as getting FR, phase, timing, and all the tuning & setup to actually have a good sounding surround sound.... well, id be interested in reading whatever you find out....
 
  • Like
Reactions: LowBassSubs

·
Registered
Joined
·
31 Posts
Discussion Starter · #5 ·
Think you already have the answer. I have no experience in what your are trying, but on a pure technical basis, where you supply an input, assign outputs, you will have sound coming out of the speakers.. As far as getting FR, phase, timing, and all the tuning & setup to actually have a good sounding surround sound.... well, id be interested in reading whatever you find out....
Ok cool thanks! I'm going to search some more and try and find out if there's anymore info on this subject. I'm always open to suggestions and knowledge so if anyone else wants to chime in I'm all ears! Thanks again for your input I appreciate it.
 

·
Registered
Joined
·
602 Posts
Why do you want to use 2 DSP's.

I can offer this, if you are using 2 DSP's, It would be much easier to use 1 DSP for say both L&R Tweets, and L&R mid-range, and use 2nd DSP for L&R Mid-Base and Subs. So Using the DSP to do your Left & Right 'pairs' of speakers, and not trying to 1 DSP for the Left side, and 2nd DSP for right side.
 

·
Registered
Joined
·
9,733 Posts
If surround sound is the goal, there are much better ways to accomplish it than using 2 DSPs. Use 1 DSP that supports surround sound. The question I have is, are you sure you want surround sound for car audio?
 

·
Registered
Joined
·
31 Posts
Discussion Starter · #8 ·
If surround sound is the goal, there are much better ways to accomplish it than using 2 DSPs. Use 1 DSP that supports surround sound. The question I have is, are you sure you want surround sound for car audio?
Not an absolute just thought it would be fun to play with😉..I have this crazy fasination to tinker with things. So to answer your question....no it's not the end goal, surround sound that is. Just want to know kinda what can be done and what can't, then let the overwhelming fascination of messing with it to inspire me or just learn everything I possibly can by doing kind of thing if that makes sense?
 

·
Registered
Joined
·
31 Posts
Discussion Starter · #9 ·
Why do you want to use 2 DSP's.

I can offer this, if you are using 2 DSP's, It would be much easier to use 1 DSP for say both L&R Tweets, and L&R mid-range, and use 2nd DSP for L&R Mid-Base and Subs. So Using the DSP to do your Left & Right 'pairs' of speakers, and not trying to 1 DSP for the Left side, and 2nd DSP for right side.
Are you basing that just off of a typical sq music type of environment or as both a sq music, surround sound environment as well?
 

·
Registered
Joined
·
602 Posts
Are you basing that just off of a typical sq music type of environment or as both a sq music, surround sound environment as well?
Based for both or either sq music and/or surround environment.

To use inverted Differential on a pair of speakers, ((inverted differential is highly needed to create surround sound)), you will need to be able to make those adjustments to an input from both left and right and output to a speaker. Its a combination of L-R and R-L (left minus Right / Right minus Left). You will not be able to create or experiment with any type of surround sound if your use a Left side DSP/Right side DSP.


EDIT:..... I take some of that statement back.... the more I think about it, the more my statement above rings NOT true........ hummm now I'm not sure.... may have to think about this one....

This is a very interesting concept...... yeah, I'm hoping others will chime in with opinions..
 

·
Registered
Joined
·
602 Posts
I have 5 dsps

one toslink , into a ddrc22 out into a optical 3way active splitter into 3 2x4hds works excellent

one of my hds analog outs go analog into a ambient processor (which makes the 5th)

WOW, Thats fricken AWESOME !!!
 

·
Registered
Joined
·
602 Posts
@oabeieo what do you think about a Left and Right side DSP? Is it doable ?
 

·
Registered
Joined
·
5,628 Posts
@oabeieo what do you think about a Left and Right side DSP? Is it doable ?
you can…. But honestly, this amp for left and amp for right , dsp for left and dsp for right is just silly…

crosstalk is hardly an issue at the electrical level…. And it makes levels setting a massive pain…. Plus the minute bias difference between amps aren’t inherent to each respective side (left and right pairs of speakers…

it’s just dumb , don’t do it , but you can and it won’t be a huge deal… it will work

The crosstalk from acoustical space is a far far far more problematic area of crosstalk….

throw some headphones on and dsp L and R, I promise it will sound way wider then any car will ever sound…. And the dsp does it just fine

i dare to suggest all these separate L and R amps and such that make such a big difference isn’t because crosstalk, but rather biasing and op amp and other differences (small gain differences probably the most) and such that makes it sound different…(not a better different either, just a different different)
 

·
Registered
2014 VW CC Sport
Joined
·
1,376 Posts
So do you have a system yet? Have you ever heard a proper active system? If you have. You would not be thinking surround sound I promise that! Just wondering if you have ever had active or tuned. Most new guys to the game always think they want rears and soon find out they aren’t even needed let alone surround sound. I come from home audio so I get why you would be thinking this way 😉. Go take a listen to some good tunes systems with center image and soundstage above the dash then come tell us you still want surround. I’m not trying to be mean or smart ass by any means, just saying you’ll change your mind
 

·
Registered
Joined
·
31 Posts
Discussion Starter · #17 ·
So do you have a system yet? Have you ever heard a proper active system? If you have. You would not be thinking surround sound I promise that! Just wondering if you have ever had active or tuned. Most new guys to the game always think they want rears and soon find out they aren’t even needed let alone surround sound. I come from home audio so I get why you would be thinking this way 😉. Go take a listen to some good tunes systems with center image and soundstage above the dash then come tell us you still want surround. I’m not trying to be mean or smart ass by any means, just saying you’ll change your mind
Thanks for the input! Took what you said as by no means offensive, I take things rather lightly and am in this world to see what I can do and concor on my own and push myself to learn! Been in the home and car audio things since I was an early teenager I find sound, physics, engineering fascinating! It's a hobby, a passion of mine and any input or criticism is taken in and absorbed because thats a key thing on helping one another learn!
 

·
Registered
Joined
·
31 Posts
Discussion Starter · #19 ·
you can…. But honestly, this amp for left and amp for right , dsp for left and dsp for right is just silly…

crosstalk is hardly an issue at the electrical level…. And it makes levels setting a massive pain…. Plus the minute bias difference between amps aren’t inherent to each respective side (left and right pairs of speakers…

it’s just dumb , don’t do it , but you can and it won’t be a huge deal… it will work

The crosstalk from acoustical space is a far far far more problematic area of crosstalk….

throw some headphones on and dsp L and R, I promise it will sound way wider then any car will ever sound…. And the dsp does it just fine

i dare to suggest all these separate L and R amps and such that make such a big difference isn’t because crosstalk, but rather biasing and op amp and other differences (small gain differences probably the most) and such that makes it sound different…(not a better different either, just a different different)
Thanks for the input! I can see how much of a pain in the butt things can get with more complexity within a system but to me that's what's fun about it! I have a question for you about the biasing aspects of multiple amps and the surround sound decoding features that can be utilized from certain sound fields that can be created from such formats, utilizing a dsp for just simple tasks in the surround sound aspect of a system, not necessarily with basic stereo formats as that can be used differently of course.
 

·
Registered
Joined
·
5,628 Posts
Thanks for the input! I can see how much of a pain in the butt things can get with more complexity within a system but to me that's what's fun about it! I have a question for you about the biasing aspects of multiple amps and the surround sound decoding features that can be utilized from certain sound fields that can be created from such formats, utilizing a dsp for just simple tasks in the surround sound aspect of a system, not necessarily with basic stereo formats as that can be used differently of course.
not exactly sure what your asking , but I’ll take a stab at what I think you’re trying to say.

as far as like surround channels, I imagine you have a decoder and a upmixer upstream Somewhere…

The surround channels obviously are not as important as far as coherence goes , although still important that the signal integrity isn’t diminished….

like in 5.1 it’s the phase differences between L and R that tells the decoder what to send where

like left and right at the same time go to the center, and then a lot of them were like a 6040 split where as it pans it goes to left and right

and then the rears are left minus right and right minus left respectively between eachother

sub and center are pretty much the same thing.
Except below 200hz (if I remember my reading properly) the center is simple L+R (hence the .1)

discrete surround is a different critter, like 7.1 logic 7 where actual ambiant tracks are embedded and such…. (You won’t want me to explain it because I am not brushed up on that very well) I just know some of the newer stuff like atmos and logic seven do some pretty advanced things.

but I think that’s kind of the gist of what’s going on so that should answer your questions

once it’s decoded you can treat it like any other speaker and measure it and tune it any which way you want, as the phase of the L and R are mostly extracted and sent and are no longer so much dependent on L and R signals having coherence. But don’t mistake out for a free-for-all
It’s still very important to have your polarities proper and in time….
 
1 - 20 of 28 Posts
Top