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Discussion Starter · #1 ·
Hey I am in search of some line drivers for the new setup I will be putting in to whichever new car I am getting in the next week or so.

The reason I want them UNDER 100 dollars is because I will be buying 3 of them UNLESS they make a line driver that will do 6 channels "front,rear,sub" since the radios that I want only have 2 volt preouts and I noticed that with my old setup just switching from my alpine that had 2 volt preouts to the kenwood kdc x790 that had 5 volt preouts there was a HUGE difference in sound quality from esesentially switching to the higher preout voltage " and YES I did re adust the gains lower there was singnificantly MORE output from all of my speakers

Jusy looking for opinions here guy's
 

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The best line drivers IMO is no line driver. Every single car I have seen a line driver installed in has had it affect sound quality negatively.

If you are dead set on one I believe that Audiocontrol may still may a 6 chan. line driver. Seriously though that money could be put to much better use in an install.
 

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Discussion Starter · #5 ·
The best line drivers IMO is no line driver. Every single car I have seen a line driver installed in has had it affect sound quality negatively.

If you are dead set on one I believe that Audiocontrol may still may a 6 chan. line driver. Seriously though that money could be put to much better use in an install.
That is strange you say that because in the 13 years I have been installing for a living I have never had a problem with a line driver having any negative effects on a setup...I know I would be better with a HU with higher preout voltage levels but unfortunately the kenwood units I am looking at "dnx 6160 OR dnx 7160" only have 2 volt preouts

I dont mind buying the audiocontrol piece even if it is more expensive " do you know a price off the top of your head btw" since one line driver for 300 dollars or so would still be about the same price as 3 line drivers for 100 bucks a pop

I have had pretty good experiences with the Rockford line driver " rockford BLD" but would prefer to have 1 line driver as opposed to 3 but if I have to I will do 3 food line drivers
 

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I misread your opening post, I thought you needed 6 channels for $100. The Matrix is about $170 and it's a 6-channel.
The three TLD22s would probably still be your cheapest bet (that's still a good product) but dealing with 3 separate chassis and 6 separate gains would be a pain. The Matrix is easier with 3 stereo gains rather than 6 individual pots.
 

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pg makes the TLD66 which is a 6 channel line driver.

Do not mount it to the chassis where it can ground out. The only time I had noise issues was when the tld chassis was grounding out and causing some static when it did. Every other time it helped the sound alot.

Now be sure to put it as close to the deck as possible though. I have seen more then a few where they mounted it right infront of the amp and when that it done it defeats the purpose as the driver amplifies the noise it has picked up.
 

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Think about what a line driver does. It amplifies. It takes a low voltage and turns it into a higher voltage.

Isn't that what an amplifier does? :)

You might want to try to figure out why your amplifier isn't up to the task. Definitely an odd problem..
 

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One more thing...

Most people don't realize this, but the gain of your amplifier is fixed. It's not adjustable. The amplifier itself has a constant gain. In car audio, many of the amplifiers have a front end that knocks down the incoming signal so that it's low enough for your amplifier. This front end is called the gain control. This is what you're doing when you adjust the gain knob -- you're knocking down the incoming signal before it ever reaches the amplifier itself. In other words, it's a volume knob. :D

It makes very little sense to me to increase the signal with a line driver, just to knock it down in the amp's front end, and then increase it again inside the amp. Some argue that it's useful because it reduces noise induced into the RCA cables. That makes sense. But in practice, IME, the noise of the system is dominated by ground loops and source unit noise, not by induced noise. I would actually bet that in most cases the line driver itself introduces more noise than what's inducted into the cables.

BTW, want to reduce inducted noise? The most effective way is to buy amps with low input impedances. Or, modify your amp's input impedance by changing the value of a single resistor per channel. :)
 

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I will have a used black AudioControl Matrix for sale very soon. $90 bucks shipped.
 

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Discussion Starter · #11 ·
Think about what a line driver does. It amplifies. It takes a low voltage and turns it into a higher voltage.

Isn't that what an amplifier does? :)

You might want to try to figure out why your amplifier isn't up to the task. Definitely an odd problem..
No no I am going to end up buying 4 of the new Polk Audio PA series amps "2 PA880.1's, 1 PA660.4, 1 PA 330.2" and I am sure they are up to the task, My concern was that the radio I was looking at only has 2 volt preouts which would cause me to have the gains up higher in order to match them to the input voltage...By using a line driver that outputs say 8 volts I could have the gains much lower in order to properly set them up with the input voltage theya re receiving
 

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Discussion Starter · #12 ·
One more thing...

Most people don't realize this, but the gain of your amplifier is fixed. It's not adjustable. The amplifier itself has a constant gain. In car audio, many of the amplifiers have a front end that knocks down the incoming signal so that it's low enough for your amplifier. This front end is called the gain control. This is what you're doing when you adjust the gain knob -- you're knocking down the incoming signal before it ever reaches the amplifier itself. In other words, it's a volume knob. :D

It makes very little sense to me to increase the signal with a line driver, just to knock it down in the amp's front end, and then increase it again inside the amp. Some argue that it's useful because it reduces noise induced into the RCA cables. That makes sense. But in practice, IME, the noise of the system is dominated by ground loops and source unit noise, not by induced noise. I would actually bet that in most cases the line driver itself introduces more noise than what's inducted into the cables.

BTW, want to reduce inducted noise? The most effective way is to buy amps with low input impedances. Or, modify your amp's input impedance by changing the value of a single resistor per channel. :)
I have just always had a positive experience when using line drivers in customers car's and generally allowed me to keep the gain lower since it was receiving a higer input voltage

The line drivers would be mounted within 12 inches of the source unit

Now keep in mind I MAY NOT need them, I wont know until I get these new amps and source unit in the car...I was mainly asking about which would be the best INCASE I decided that I needed them or that they would benefit the system

I am NOT just buying line drivers to buy them, I will ONLY buy them if once everything is installed it is determined that they would be helpful
 

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I've got a pair of zapco slb-tp4's totally 8channels if you're interested. I didn't read the whold thread so I don't know what amps you're running.

Drop me a PM if interested.
 

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There's nothing wrong with having the gains high. All it means is that you're cutting the incoming voltage less.
 

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Discussion Starter · #16 ·
I've got a pair of zapco slb-tp4's totally 8channels if you're interested. I didn't read the whold thread so I don't know what amps you're running.

Drop me a PM if interested.
I will let you know, I will be using 4 of the new Polk PA series amps
2) 880.1's
1) 660.4
1) 330.2 since I can get all four amps for under 250 dollars TOTAL
 

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Discussion Starter · #17 ·
There's nothing wrong with having the gains high. All it means is that you're cutting the incoming voltage less.
In my experience though "mainly with amps running mids/highs and not so much subs" is that having the gains turned to high CAN cause noise to be picked up which is why I always buy a much larger amp than needed in order to keep the gains low to keep noise out "not that I have ever had noise in ANY of my setups but I always am cautious"
 

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Think about what a line driver does. It amplifies. It takes a low voltage and turns it into a higher voltage.

Isn't that what an amplifier does? :)
This is about the best post I have ever read on a car audio forum about line drivers.

What most folks fail to realize is that car audio line amplifiers or line drivers came into existence in mobile audio at a time when early sound-off competitors were prohibited from adjusting their amplifier gains in competition for I believe the SQ/SQL side of things. They eventually found a way around those rules by installing line amplifiers or line drivers which essentially did the same thing as raising the sensitivity gain adjustment on the amplifier.

Eventually the marketing folks got a hold of this and now the line driver seems to be a cure for everything.
 

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Discussion Starter · #19 ·
This is about the best post I have ever read on a car audio forum about line drivers.

What most folks fail to realize is that car audio line amplifiers or line drivers came into existence in mobile audio at a time when early sound-off competitors were prohibited from adjusting their amplifier gains in competition for I believe the SQ/SQL side of things. They eventually found a way around those rules by installing line amplifiers or line drivers which essentially did the same thing as raising the sensitivity gain adjustment on the amplifier.

Eventually the marketing folks got a hold of this and now the line driver seems to be a cure for everything.
I agree, go back and read my last few posts and you will understand my thoughts about the line driver
 

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Line drivers were useful back when HU did 1V output, I have no doubt about that. But with 2V HU I've rarely had a problem. Can you get more out of an amp with higher? Maybe, the old LP amps they said 5V was ideal and at the time it seemed to work. But now power is cheap and you don't need to wring every last drop out of an amp, and some (most that I've seen) amps are only going to do what they do and no more. And most amps don't work like LPs they loved more input. So it really depends on how high the amp will gain, as some do and some don't. Having tested a lot of amps on a 2V HU, the ones with bass boost tend to gain less some you have to use the boost just to get it to clip. Could you have a noise issue that it can help, maybe but not that often. IMO I usually need a better amp if I need a line driver, since I don't do SPL where it might maybe help me. If I can't get clipping with the amps own gain on a 2V HU, then I change amps. Often if I get noise problems a better amp will cure it.

Why don't I like line drivers....well one with an EQ can be nice such as the old PA2 from LP. But with a DSP HU or even a crossover in the HU, they are of little use. Mostly I don't like anything in the signal path, because its the worst source of noise and distortion in my experience. Don't ever use a cheap xover or line driver or EQ unless you have proof it is a clean unit, you can degrade system performance the fastest that way. Remember any noise it makes gets amplified, that means multiplied. I only used LP, Nak, some Alpine and RF, and some Audiocontrol products for that stuff. Most others sucked, but not used any in quite a while excepting an alpine.
 
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