New System Design

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Ok, so this is one of, if not my first post here, I usually hang around DIYMobileAudio.com, as I am big into car audio and compete in sound quality competitions. I looked for the answers to my questions in the forum, and came up negative. Anyways, I am looking to build my first HT setup, and everything seems more confusing than it is in car audio, same principals, but different components. In my car, I run my HU (running 3 way active, all Time Aligned) into my amps, into my drivers, pretty straight forward.

I want to build a pair of 3 way tower speakers (or 4 way if I incorporate the sub) using Dayton's Reference Line drivers, as I hear great things about them and it seems hard to beat them for the price point. But where I am getting confused is how does everything connect. As far as the cabinets go, I am assuming (from the drivers) you would hook up the drivers to the crossovers, crossover to amp, and then from there it all gets kinda fuzzy. I have a 7.1 Sony receiver right now, albeit not the greatest, but the price (free) could't be beat. it is supposed to do 100w/ch @8ohm @.03THD. Can this be used with a 2 way setup, would I need a multi channel plate amp to mount in the cabinet, if so, how would the inputs on the amp work, and where would they come from?

This is where I am really confused, and I am sure I am making it more complicated than it really is. I am pretty good with xo's, boxes, driver matching, etc, but this diy home audio is all a new world to me. The most I have got into it is hooking satellite speakers into my sony receiver, and changing out some drivers on some crappy pioneer satellite speakers.

Any help would be greatly appreciated.

Kyle
 
Home audio speaker design is nothing like car audio, so I hope you dont think you can just design a speaker with text book designs.

As far as the chain goes

Source - receiver (preamp and amp combined) - crossover - drivers

Yes you can use a multichannel receiver for stereo.
 
Thanks for the reply Jay, I guess where I am getting confused is in the receiver, preamp and amp area. And I don't know what you mean by text book designs? I have always used calculations and programs like WinISD to help with my designs, and choosing drivers / enclosures. My design will most likely include boxes inside of the cabinet, each driver having it's own appropriately sized box, either vented or more likely sealed. If this is incorrect, I would love to know before I get too deep into the design process.

Also, if I use my receiver for stereo, would it need to go into a separate amp since it will be driving more drivers than just 1?

Another question, if you run an amp into a crossover or multiple crossovers, how does running (3) 8ohm drivers affect the amp load?
 
You're not that far off track.

A 7.1 receiver is intended to drive 7 speakers and a sub.

If you want to drive a stereo pair built with passive crossovers, you could just ignore 5 channels and the .1(sub). A correctly designed crossover will mean that the 3 * 8 ohm drivers appear as a single 8 ohm load.

You could wire all this lot up in a number of different ways.

You could use a line level crossover to split each channel into three frequency bands, send the resulting 6 signals to 6 of the channels and drive each driver individually. This requires a bit of manipulation, because the drivers will probably have different efficiencies, and this will result in an unbalanced sound if not accounted for at the crossover or elsewhere. To get a good understanding of this you could try Doug Self's book, The Design of Active Crossovers.

I haven't said anything about the sub. In HT systems there is typically one sub, this is the .1 in the 7.1. The 7 channels are left, mid, right, surround left, surround right, surround back left and surround back right.

Often the sub channel is provided with twice as much power output as the other channels. You'd have to decide whether you wanted to stick with what you've got or add a second sub channel. Since bluray and other sources generally have a single sub channel, it's probably better just to stick with the one, but there are lots of different arrangements and no sign of things settling down to a standard, with this exception.

HDMI, which is the HDTV interconnect cable, has 7.1 sound capability, which makes it a strong contender to become the eventual standard.
 
Thanks for the reply Jay, I guess where I am getting confused is in the receiver, preamp and amp area. And I don't know what you mean by text book designs? I have always used calculations and programs like WinISD to help with my designs, and choosing drivers / enclosures. My design will most likely include boxes inside of the cabinet, each driver having it's own appropriately sized box, either vented or more likely sealed. If this is incorrect, I would love to know before I get too deep into the design process.

Also, if I use my receiver for stereo, would it need to go into a separate amp since it will be driving more drivers than just 1?

Another question, if you run an amp into a crossover or multiple crossovers, how does running (3) 8ohm drivers affect the amp load?

Are you planing on running an active crossover? In that case you will need a seperate amp (receiver) channel for each driver, or series/parallel pair of drivers. You will of course need something like a DSP to act as an active crossover. You will then need to measure the response of the drivers, and set their levels/slopes/phase for proper integration.

If you want to do a passive design, well that's a lot more complicated (what I was referring to with text book designs)...
 
Thank you both for the info. I guess what I had envisioned was maybe running a 3 ch plate amp so each driver would have their own channel, and putting a x-over between the amp and driver, however I wish I could do it before the amp so the amp isn't amplifying the whole freq range in each channel, but oh well. Also, with the levels of the drivers, I would need to attenuate the tweeter about 6db, would this be possible with an L-pad, or is that just for correcting impedance?

In my car I am running a 3 way active x-over, and I would imagine that it would be simpler to change x-over points and slopes that way, but, again, I could be completely wrong, lol. If you did do an active x-over, and had a 3ch amp, you would have to have an input for each channel, correct?

I Thought about using something like Dayton Audio XO3W-375/3K 3-Way Crossover 375/3,000 Hz 260-150 but what about driver RMS? If a 7" can handle 60 WRMS, and the tweeter can handle only 30 W RMS (and say 50 for mids) that means you are limited to only 90 w/ch, 90 divided by 3, and only 30w to each channel. The tweeter has a 4db higher effeciency rating, which wouldn't be too bad if you could drive the woofers with twice the power, but how could you in that situation?

Car audio is so easy in comparison, each channel set has it's own input sensitivity that you can adjust the output with, and each channel has it's own x-over setting, all available on the amp itself, lol. I am so lost...
 
HDMI, which is the HDTV interconnect cable, has 7.1 sound capability, which makes it a strong contender to become the eventual standard.

Do you know anything about the hdmi cable specification?

Long time ago I searched the net with no result. I have a DVD player that outputs through HDMI (RCA output is broken). I want to extract the audio signal from this (instead of the DOUT).
 
I think building a proven design first would be greatly beneficial, thinking something like this TriTrix MTM TL Speaker Components And Cabinet Kit Pair 300-702 would be decent, having to build the crossover itself, and getting an idea how everything works together.

The HDMI cables that I use are rated for 1600p at 240 fps and at 48 bit depth. Not sure about the audio, but since they are from an audio manufacturer, I am sure they are fine in that area
 
Well, now you're right back to trying to design your speaker, which brings up the original issue 😀

There are dozens of designs using the Dayton RS drivers. The DC28F is generally considered a low quality tweeter, there are much better performers for the same price.

The Tritrix gets the most performance possible out of those Dayton classic driver.

I have built my own boxes and what not in car audio, but I was also looking at buying just the cabinet, and using Daytons Reference line drivers, using the Dayton Audio DC28F-8 1-1/8" Silk Dome Tweeter 275-070 with probably the Peerless 830991 5-1/4" GFC Cone HDS Woofer 264-1074 or maybe Dayton Audio DC130A-8 5-1/4" Classic Woofer Speaker 295-303. Although I have the Peerless HDS 6.5" running in my car, and I really like those things. Thoughts?
 
Do you know anything about the hdmi cable specification?

Long time ago I searched the net with no result. I have a DVD player that outputs through HDMI (RCA output is broken). I want to extract the audio signal from this (instead of the DOUT).

Yeah, I know a bit about it. It will carry up to 8 channels of 24/192 linear pcm.

You can get a device to extract audio from HDMI but they're comparatively expensive because of licensing considerations. The easy (cheap) way to get access to (stereo) sound from HDMI is to use a TV and take the output from one of the audio outputs, for example play a CD using the DVD player, you'll get an onscreen menu allowing you to pick tracks, or if you're watching a DVD pipe the TV output through your audio system, if nothing else the TV should have a headphone out, most do these days.
 
It will carry up to 8 channels of 24/192 linear pcm.

You can get a device to extract audio from HDMI...

The easy (cheap) way to get access to (stereo) sound from HDMI is to use a TV and take the output from one of the audio outputs...

Thanks CC. 24/192, that's good.

So HDMI is digital and in an uncommon format.

I have never used TV audio out so I don't know if there's RCA out. If there is RCA out, it means in the TV there is special DAC that convert the HDMI digital format to analog. I will try to find this RCA out soon.

Also, with the levels of the drivers, I would need to attenuate the tweeter about 6db, would this be possible with an L-pad, or is that just for correcting impedance?

To correct impedance you use zobel (RC). The L-Pad is indeed to pad down the level (the series R to pad down, the shunting R to bring back the impedance).

Thanks kyle for allowing me to use your thread for getting some info on the HDMI thing.
 
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