Stereo Gurus - FARK Questions

[mattyjman]

bump for an answer on balanced or unbalanced.

[RedWingsZL1]

Installed my NX4 using just the FARK 3.0 kit and a 4GAU wiring kit. No problems with loud chimes or anything. Tested it at both 2ohm and 4ohm as I ran the stock BA speakers for a day or so. Currently have Pioneers in which are 4ohm, system sounds great.

NX4 says it pumps out 100W x 4 channels at 4ohm. Not having any problems.

[mattyjman]

well, I finally got an answer to my question from Steve through PM... :

my question:

I've heard the HU (2013 MYLINK Touch screen/ BA Premium) outputs a 8v "BALANCED INPUT" signal to the amp vs sending a more common unbalanced signal? Is this true? (here is a reference post explaining the difference - everything is accurate except the last line about it not existing in car audio - since 2007, it is quite common)

and the answer...

Originally Posted by Steve@********

Whatever comes out of the radio.

Now, I'm not sure if this is said tongue and cheek, or sarcastic, or if he really doesn't know, but is this the level of service that other people have gotten from him? I'm really surprised at how unhelpful this answer was, as well as how little importance is put on something critical.

i know from reading on the forums that many people have reported noise issues for various reasons, and there are some amps that work better with the fark kit, than others.... and this could be the very answer. This is what I'm trying to determine before I wrap up my install, and this level of service is what I get.

Can anyone else clear up this issue for me, or am I better off getting a RTA and O-Scope and figuring it out myself?

[SSMickey]

I would call Todd at TC Audio and discuss your concerns with him. One of his design goals in his car was to retain the factory HU. I don't really think Steve@******** is really into the critical listening side of car audio, so it sounds like your question might have confused him a bit.

[darkrider01]

I have the o-scope, but I don't have the radio installed any longer. Why exactly is it so critical for you to have one or the other? Noise?

Also, calling TCAudio would probably get you the most information.

[mattyjman]

Originally Posted by SSMickey

I would call Todd at TC Audio and discuss your concerns with him. One of his design goals in his car was to retain the factory HU. I don't really think Steve@******** is really into the critical listening side of car audio, so it sounds like your question might have confused him a bit.

Originally Posted by darkrider01

I have the o-scope, but I don't have the radio installed any longer. Why exactly is it so critical for you to have one or the other? Noise?

Also, calling TCAudio would probably get you the most information.

thanks for the suggestions guys... I'll look into that.

As to why this is important... I'm surprised this hasn't come up yet actually, and if it did, I totally missed it.

First, I'm putting a lot of time and money into the system, and I want to make sure everything works in pristine order. I have over 3500 in just the amps alone. I'm not installing some rockwood knock off brand.

I'm putting in nice gear... sure. But I still don't get it.

So, the question is are the outputs "balanced" or "unbalanced". How many people on here have mentioned noise issues, complications with something noise related after using the fark kit? I've read numerous examples, and now you get people on here recommending certain amps, because others cause issues. The only reason why a certain amp would cause issues in an install (at least noise related - and not relating to FM radio frequencies and the such) is because it doesn't like the signal it's getting, OR it was installed SUPER poorly.

Assuming people buying an amp that is a few hundred dollars find out how to install them correctly, that only leaves the other alternative. Which get's back to my question, balanced or unbalanced.

Unbalanced is the traditional rca... it sends signal through the middle wire, and the outer wire is ground. This is how most amps are built to take a signal. Assuming that the signal is powered enough, even the cheapest of amps built correctly shouldn't have an issue with a correct install, in any car, or with any unbalanced adapter.

Balanced signal is where the positive and negative signals travel in each wire... doing this actually cancels any noise an rca can pick up due to power wire, interference, etc. This is not commonly supported in amps, but some do and/or have the capability to accept the signal with no setting changes required from the end user.

Being that not all amps will accept the balanced signal, it seems plausible that this is the type of signal that we get from the fark kit, and why only some amps seem to work with the kit.

Particularly in my case, my processor - Audison BitOne- doesn't really do well with balanced signal, which will throw a wrench in my install and gear lineup. And with the horns that I'm installing (very very very sensitive) any noise that comes through the amps will be amplified, and even the littlest bit will annoy me.

I could be totally wrong here. I'm making a big assumption as to why some amps work and some don't. But there are only a few logical alternatives.

A simple question, not such a simple answer. Based on this question though, I think a lot of people would be very interested in the response to the question at hand... it would at least allow us to pick the right equipment to go with our installs.

[darkrider01]

I think you have totally misunderstood the issue that some amps have and some amps do not have with the stock head unit. It's not a noise issue - the issue is how and when the stock head unit terminates it audio output versus when it terminates its remote output. I have a very lengthy thread linked in my signature that addresses that issue. The whole time you have been talking about the unbalanced versus balanced output I've been wondering if the BitOne would keep you from having the turn-off pop that I (and several others) had. I really think that the turn-off pop is related to amplifier topology. I think that the Class A/B amps have issues whereas Class D do not. I'm interested to see if your amps have the pop. I believe all of the amps that people say don't have the pop are all full range Class D. I know those Mosconi's are Class A/B and Class A.

I don't remember anyone complaining specifically about any of the amps having hiss or other noise floor related issues.

I don't know - you might be lucky and the new MyLink heads might be completely different than the older style, but I doubt it (the brain units appear to be identical).

I don't understand keeping the stock head unit if you're this concerned with your signal path. Why not replace the MyLink with a nice shiny Pioneer DEX-P99RS or a McIntosh MX406? Either of those head units would look super sexy in the Camaro (at least IMO). I really wanted to keep my stock head unit originally as well, but in the end, it really wasn't worth it.

I really wish you the best on this endeavor. I'd love to hear the finished product some day.

[mattyjman]

maybe I'm misread everything... I'll look through your post to see what's really going on. Did you ever try a relay?

[darkrider01]

Yeah, I tried a relay but the factory radio didn't produce enough current to actuate it.

[mattyjman]

even with a 12v constant? that's wierd...

[darkrider01]

Originally Posted by mattyjman

even with a 12v constant? that's wierd...

It all goes back to how the stock amp operates. When the head unit terminates its output, it actually sends a mute signal to the amp. Now this is pure speculation as I have not opened up the stock amp, but I believe that the stock amp internally disconnects the ouputs on signal from the mute. The remote wire continues to stay powered on for several minutes after the key is removed, etc.

So my idea was to use the mute signal to break the remote connection by using a NC relay. The mute signal is around 6V, so I picked up a micro relay from "The Shack" to perform this function. Unfortunately, the mute output only provides 1.9mA of the needed 56ma required to operate the relay.

[mattyjman]

still haven't had time to dig into this, but what's kept you from finding another remote? the amp isn't the only one...

[crashprime]

I think the remote signal on the stereo/amp is the only one that will work with the keys out of the ignition but the door open.

There are a number of folks using the cigarette lighter for their remote, and the only drawback as far as I can tell is the fact that the keys must be in AUX for the amps to turn on.

[mattyjman]

^ or start, obviously. so it functions just like any normal switched 12v lead would...