cheapest way to add time delay? any ideas?

[corcraft 10+ year member]

I just bought an alpine pxe h650 to start building my system with. However, it only offers 10ms of time delay (which is double the 3sixty) but I'm going to need 20 for rear fill. Any ideas?

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[corcraft 10+ year member]

Basicly I'm wanting to know if there is a cheap 1 or 2 channel processor out there that adds at least 10ms of time delay that I can put in line with my pxe (10ms).... And of coarse any other ideas will be greatly appreciated as well. Thanks

 

[tc300 10+ year member]

what is the purpose of this again..??????

 

[corcraft 10+ year member]

Rear fill should be delayed around 20ms.

 

[tc300 10+ year member]

for what reason????

 

[galacticmonkey 5,000+ posts]

Put a flux capacitor inline with your rear speaker wires. That will allow you to dial in the time delay you want, as well as travel time itself.

 

[quins90lac 10+ year member]

buy what you need to begin with . NOOB

 

[corcraft 10+ year member]

Lol, noob??? I was sponsered for 2 years by infinity with a high in line called beta that you probably never heard of because only 52 elite infinity dealers in the US could carry it. That was 10 years ago and I still have my alpine digital time delay pra h400 processor from then when most people (probably including yourself quin) didn't even know what time delay was. Def not a noob but have been out of the game for a while. I just asked a simple question and if you don't know the answer "noobs" then don't reply.

 

[corcraft 10+ year member]

And as far as "buy what you need to begin with" I think that I bought the best processor available for oem interface, I just need a little more time delay and I bought the processor with the most delay but still not enough for rear fill.

 

[keep_hope_alive Premium Member]

you can cascade processors to get an additional 10ms of delay. i haven't seen any simple in-line active devices that give you delay. i thought i remembered a few amplifier manufacturers who made delay add-ons for some high end amps. maybe something like that could be modified and added?

is 20ms calculated based on cabin volume or is that a generic rule of thumb you use?

the idea behind rear fill, for me, is to give the effect of a room or larger space. similar to listening to speakers in a room where you get reflections that are filtered based on the absorption of the room. those reflections are delayed based on the size of the room and the distances involved. IMO rear fill shouldn't be full range, but filtered - bandpassed at least, since room reflections are also filtered. you could use absorption coefficients or equivalent octave band sabins of a properly acoustically treated room as your starting basis. as someone who designs acoustical treatments for performance spaces - i can tell you that the information is fairly easy to come across and just requires some math. i have developed software for creating auralizations of rooms/spaces, and also spreadsheets for easily calculating equivalent sabins based on area of materials. just finding all of the associated absorption coefficients requires the most time. the real trick is that a properly treated room has diffuse reflections - something that is tricky in a car.

the H701 gives 20ms in .05ms steps. maybe you use a different processor that meets your needs?

 

[corcraft 10+ year member]

Hey, Thanks for your input. As far as the 20ms, yes, that's just a rule of thumb and then I play with it from there- 20ms more than the front that is.. Much less and you usually get an "echo" effect. Yes I like rear fill to be in the ranges of 300 and 3000hz and mono. Again that's just a rule of thumb and I play with those frequencies. I couldn't use the 701 because I needed an oem interface processor. It was this alpine, rockford 3sixty which only has 5ms of time delay, mtx and jl cleansweep has no time delay and that leaves the jbl which I did not research. I still have a h400 but time delay doesn't work without ainet- that's what alpine told me years ago anyway. I think I may just but another 650 but I hate to spend the money just to use 2 channels of time delay which is why I created this post- to see if any1 made a processor that was simply a 1 or 2 channel time delay and that was it. Thanks again

 

[keep_hope_alive Premium Member]

sounds like you know what you need and you know what you want. good luck.

Phoenix Gold TiDEQ is an option, but overkill for only rear fill. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[corcraft 10+ year member]

Ok, I did some searching and here are a couple of links to explain the 20ms that I am wanting for rear fill. The bottom link is the most informative but some "noobs" may not understand it.

diymobileaudio.com/forum/diyma-sq-forum-technical-advanced/71218-rear-fill-l-r-stereo-mono-question-2.html

caraudiocentral.net/forums/showthread.php?1969-Rear-fill-speakers

 

[Jroo 10+ year member]

no real cheap way. If you have the alpine process, I would look for used Ai decks. Many of the alpine decks from those years go pretty cheap now and that would give you access to the time delay you need. Have you ever tried to go with out rear fill? I dumped mine years ago and have never looked back. My DSP and processing was never that great, but I dont miss the rear fill at all. BTW, we had a Beta dealership here and I still have my beta mids and tweets. The best truck I ever heard was a Beta Asto van using McIntosh amps and a Denon head they sponsored. Truck was all Beta and had 4 12's, 6 midbass and a 4" and Beta ones in the dash. Clean and loud is all I can remember.

 

[keep_hope_alive Premium Member]

both are good reads. i still haven't seen a calculation for the delay, just a general rule of thumb that is combined with experience and equipment limitations. I like calculations, it shows there was some thought into the number(s) and helps you derive your own. i haven't thought about what size room i'd like to simulate and how best to incorporate that into rear speaker locations.

I like L-R and R-L from a surround sound application, but a room has vocal reflections in it as well. so I think the argument against having vocals as part of the surround information is mostly based on phase interference with the center image.

I am using the center channel output of my H701 in 3-channel mode in order to get an L+R mono rear signal.