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#1
Posted to rec.audio.car
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RCA Output voltage
I was curious to know does it matter the amount of voltage a hu put out
to the rca jacks? I have a Boss hu and it says it has 5 volt pre amp outs. I am fixing to get a new car in which I will be purchasing a new hu, and I wanted to find out if the voltage output was something to weigh into the decision. Thanks in advance for any and all suggestions. |
#2
Posted to rec.audio.car
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RCA Output voltage
A couple of things. First, when a HU says 4 or 5 volt pre-amp (RCA) output,
that is a maximum number. Nominally, your HU typically puts out a much lower voltage. Also, pretty much EVERY HU made today puts out AT LEAST 2 or more volts which, 15 years ago, was considered high voltage. So there really isn't much difference between the high voltage and low-voltage outputs. Second, I have owned a high voltage (4 volts) HU (an Alpine 7939) and several non high voltage HU's (2-3 volts) including my current HU, an Alpine 9853, and I don't notice any difference in sound quality. I think this whole voltage thing has more to do with marketing than any meaningful sound quality improvement. As I frequently point out, if 4-5 voltage pre-amp outputs were the end-all-be-all, why don't multi-kilobuck high-end home equipment (Mark Levinson, Krell, Conrad Johnson, etc.) use them? The answer is that THEY DON'T help sound quality wise. What they CAN do, however, is sometimes cover up induced noise problems (like alternator whine caused by ground loops) by allowing you to turn the gains on your amp lower. However, I see this as a band-aid. A 5 volt pre-amp output may allow you to REDUCE noise problems, but it can never ELIMINATE them. A good installation with proper grounding on all components CAN ALWAYS (at least in my experience) eliminate ground-loops. And other types of induced noise can be dealt with as well. To me, it makes more sense to deal with the problem, rather than trying to cover it up. So for that and other reasons, I don't see much benefit in high voltage outputs (of course, I don't think a high voltage output HURTS anything). I just wouldn't make that a very high priority in selecting a HU. My $.02, MOSFET "Deez Nutz" wrote in message oups.com... I was curious to know does it matter the amount of voltage a hu put out to the rca jacks? I have a Boss hu and it says it has 5 volt pre amp outs. I am fixing to get a new car in which I will be purchasing a new hu, and I wanted to find out if the voltage output was something to weigh into the decision. Thanks in advance for any and all suggestions. |
#3
Posted to rec.audio.car
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RCA Output voltage
High-voltage outputs theoretically *allow for* greater dynamic range, better
noise *immunity* (not just covering it up), and overall better S/N. To see any REAL benefit from it, however, your next downstream component (amp, crossover, whatever) needs to be able to accept the greater input. If your amp's input clips any anything over, say, 2V, you won't be able to crank the deck's output any more than you would a standard deck, and you won't see any significant difference. As an example, if your system has a noise floor of 0.05V (I'm just pulling numbers out of my ass here for the sake of illustration, BTW - these things are normally measured in dBu, dBV, or other similar scales, rather than in absolute voltages), and your deck has a max output of 1V (actually, I think 1.8V is most common, but I'll use 1V for easier reference), the noise will be a lot more noticeable than if your deck can push signal at 5V, and thus much higher above the noise floor. (Just a quick calculation in my head, I believe the 1V example would be only a 13dB S/N ratio; the 5V example would allow up to 20dB... assuming, again, that the amp or crossover's input can accept that level). This actually is not a new concept... pro audio gear has for decades traditionally used +4dBm as a "standard" signal level, while consumer (home) audio equipment uses -10dBm. Connecting, say, a home tape deck's output to a pro mixer's input requires a lot of input gain, and with it increased chance of noise, while feeding a pro mixer's output to a home tape deck requires careful control of the output gains to avoid clipping the deck's inputs. Pro gear, of course, uses the "hotter" signal for exactly the same reason: better dynamic range, better noise rejection, better S/N ratio. MOSFET wrote: A couple of things. First, when a HU says 4 or 5 volt pre-amp (RCA) output, that is a maximum number. Nominally, your HU typically puts out a much lower voltage. Also, pretty much EVERY HU made today puts out AT LEAST 2 or more volts which, 15 years ago, was considered high voltage. So there really isn't much difference between the high voltage and low-voltage outputs. Second, I have owned a high voltage (4 volts) HU (an Alpine 7939) and several non high voltage HU's (2-3 volts) including my current HU, an Alpine 9853, and I don't notice any difference in sound quality. I think this whole voltage thing has more to do with marketing than any meaningful sound quality improvement. As I frequently point out, if 4-5 voltage pre-amp outputs were the end-all-be-all, why don't multi-kilobuck high-end home equipment (Mark Levinson, Krell, Conrad Johnson, etc.) use them? The answer is that THEY DON'T help sound quality wise. What they CAN do, however, is sometimes cover up induced noise problems (like alternator whine caused by ground loops) by allowing you to turn the gains on your amp lower. However, I see this as a band-aid. A 5 volt pre-amp output may allow you to REDUCE noise problems, but it can never ELIMINATE them. A good installation with proper grounding on all components CAN ALWAYS (at least in my experience) eliminate ground-loops. And other types of induced noise can be dealt with as well. To me, it makes more sense to deal with the problem, rather than trying to cover it up. So for that and other reasons, I don't see much benefit in high voltage outputs (of course, I don't think a high voltage output HURTS anything). I just wouldn't make that a very high priority in selecting a HU. My $.02, MOSFET "Deez Nutz" wrote in message oups.com... I was curious to know does it matter the amount of voltage a hu put out to the rca jacks? I have a Boss hu and it says it has 5 volt pre amp outs. I am fixing to get a new car in which I will be purchasing a new hu, and I wanted to find out if the voltage output was something to weigh into the decision. Thanks in advance for any and all suggestions. |
#4
Posted to rec.audio.car
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RCA Output voltage
i havent read all the dribble others have wrote but i know
this........(((5v is very very good))) cause alot of amps wont take more than that but they could start making amps to take more volts from outputs. i have 2 jensen cd players with 5v outs...i love them more than any other piece of car audio i ever owned.. the sound is increditable. yes it makes a giant difference... never go under 5v outs... |
#5
Posted to rec.audio.car
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RCA Output voltage
also you look at high priced recievers theyll have 5v outs......
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#6
Posted to rec.audio.car
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RCA Output voltage
heres 1 of my secrets. go look at a $500+ reciever n try to find 1 like
its specs for less. |
#7
Posted to rec.audio.car
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RCA Output voltage
Pro gear, of
course, uses the "hotter" signal for exactly the same reason: better dynamic range, better noise rejection, better S/N ratio. Pro gear typically uses balanced signals, unlike home and car pre-amp outputs, which COMPLETELY irradiates extraneous noise (which is necessary in a pro environment where you typically have VERY long pre-amp runs AND all sorts of electromagnetic interference). MOSFET |
#8
Posted to rec.audio.car
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RCA Output voltage
better
noise *immunity* (not just covering it up), How is better noise immunity NOT covering noise up? THINK about it. It's the same thing, Matt, just another way of looking at it. I mean, you either have a noise problem or you don't, right? So IF YOU DO, and your "noise immunity" (as you call it) comes into play, explain to me how that is not just another way of saying covering up the noise. Sometimes I get the feeling your turning into Captain Matt. MOSFET |
#9
Posted to rec.audio.car
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RCA Output voltage
And one more thing, while we're on the subject, Matt....
How about answering the OP's question? I mean, your post was VERY impressive sounding and all (even though it made about as much sense to me as one of Bob's rants). But I reread it and noticed you didn't answer the question. QUESTION: Deez wants to know will a high voltage HU make an audible difference: ANSWER: Brandonb: Nope Me: Tried both kind, didn't hear a difference. You: Theoretically blah blah noise floor at -10dBm vs. +4dBm dBu, dBV, DVD, VCR, ESPN blah blah blah.... Will Deez hear a difference, Matt? Yes or no? MOSFET |
#10
Posted to rec.audio.car
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RCA Output voltage
MOSFET wrote:
Pro gear, of course, uses the "hotter" signal for exactly the same reason: better dynamic range, better noise rejection, better S/N ratio. Pro gear typically uses balanced signals, unlike home and car pre-amp outputs, which COMPLETELY irradiates extraneous noise (which is necessary in a pro environment where you typically have VERY long pre-amp runs AND all sorts of electromagnetic interference). "Irradiates"? Heheheh... only in a nuclear-powered system Not all pro components have balanced I/O... most, but not all. Balanced I/O reduces and ALMOST completely erradicates (I think that's the word you were after) noise *induced in the wiring* (not completely, and not in all instances - check out various stories around the 'net of church sound systems pickup up truckers' CBs!) but have no effect on various noise floors inherent in all electronic gear. |
#11
Posted to rec.audio.car
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RCA Output voltage
MOSFET wrote:
And one more thing, while we're on the subject, Matt.... How about answering the OP's question? I mean, your post was VERY impressive sounding and all (even though it made about as much sense to me as one of Bob's rants). But I reread it and noticed you didn't answer the question. QUESTION: Deez wants to know will a high voltage HU make an audible difference: ANSWER: Brandonb: Nope Me: Tried both kind, didn't hear a difference. You: Theoretically blah blah noise floor at -10dBm vs. +4dBm dBu, dBV, DVD, VCR, ESPN blah blah blah.... Will Deez hear a difference, Matt? Yes or no? Now I'm starting to wonder if Howdy has jacked your account, or if you're just being intentionally obstinate? Got a touch of the PMS? I answered his question in my post: it CAN make a difference IF he uses other downstream equipment (crossover or amp) that can accept the hotter signal. I answered that RIGHT AT THE TOP and then went on to explain WHY that is. Whether Deez will actually hear a difference, nobody here can say. I don't know what the rest of the his system is like, if he has shyte speakers, or if he's tone-deaf. He might drop tens of thousands into a system and not be able to hear the difference between that an a stock AM radio. |
#12
Posted to rec.audio.car
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RCA Output voltage
No, it irradiates the noise so it can't be handled for several thousand
years. That get's rid of it!!! MOSFET "Matt Ion" wrote in message news:73FJg.489044$iF6.65770@pd7tw2no... MOSFET wrote: Pro gear, of course, uses the "hotter" signal for exactly the same reason: better dynamic range, better noise rejection, better S/N ratio. Pro gear typically uses balanced signals, unlike home and car pre-amp outputs, which COMPLETELY irradiates extraneous noise (which is necessary in a pro environment where you typically have VERY long pre-amp runs AND all sorts of electromagnetic interference). "Irradiates"? Heheheh... only in a nuclear-powered system Not all pro components have balanced I/O... most, but not all. Balanced I/O reduces and ALMOST completely erradicates (I think that's the word you were after) noise *induced in the wiring* (not completely, and not in all instances - check out various stories around the 'net of church sound systems pickup up truckers' CBs!) but have no effect on various noise floors inherent in all electronic gear. |
#13
Posted to rec.audio.car
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RCA Output voltage
So your answer is "it might, or it might not but I'm going to pick apart
everything MOSFET said instead of giving you a straight answer". OK, fine, Matt. You are TRULY effecting my enjoyment of this newsgroup and I'm considering putting you on my blocked list (though most of your posts are intelligent and insightful so I don't want to). But listen to me, PLEASE. Why don't you put me on your blocked list. I'm dead serious. Obviously there's something that bugs you about my posts because you nitpick nearly every one. PLEASE PUT ME ON YOUR BLOCKED LIST! Thank you, Nick MOSFET "Matt Ion" wrote in message news:O7FJg.489050$iF6.415856@pd7tw2no... MOSFET wrote: And one more thing, while we're on the subject, Matt.... How about answering the OP's question? I mean, your post was VERY impressive sounding and all (even though it made about as much sense to me as one of Bob's rants). But I reread it and noticed you didn't answer the question. QUESTION: Deez wants to know will a high voltage HU make an audible difference: ANSWER: Brandonb: Nope Me: Tried both kind, didn't hear a difference. You: Theoretically blah blah noise floor at -10dBm vs. +4dBm dBu, dBV, DVD, VCR, ESPN blah blah blah.... Will Deez hear a difference, Matt? Yes or no? Now I'm starting to wonder if Howdy has jacked your account, or if you're just being intentionally obstinate? Got a touch of the PMS? I answered his question in my post: it CAN make a difference IF he uses other downstream equipment (crossover or amp) that can accept the hotter signal. I answered that RIGHT AT THE TOP and then went on to explain WHY that is. Whether Deez will actually hear a difference, nobody here can say. I don't know what the rest of the his system is like, if he has shyte speakers, or if he's tone-deaf. He might drop tens of thousands into a system and not be able to hear the difference between that an a stock AM radio. |
#14
Posted to rec.audio.car
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RCA Output voltage
You really should reread that post of yours and ask yourself "do I REALLY
expect the OP to understand all of this?" because you don't explain ANY of the terms you use. If you look at my posts, you will notice that I explain terms like signal to noise ratios and dynamic range and so on (in fact, I pretty much explain EVERY acronym I ever use). Be honest with yourself, Matt. Did you REALLY intend the OP to learn from what you wrote, or was this an attempt for you to use a lot of terms YOU KNEW most people would not understand in an attempt to sound superior and smarter (smarter than ME in particular). BE HONEST. Again, reread that post of yours. THINK about the original poster (who he is, how old he might be, etc.). Remember what we are here for, to HELP people. If that is your goal (as it is mine), you are tripping over your ego. Nick "Matt Ion" wrote in message news:O7FJg.489050$iF6.415856@pd7tw2no... MOSFET wrote: And one more thing, while we're on the subject, Matt.... How about answering the OP's question? I mean, your post was VERY impressive sounding and all (even though it made about as much sense to me as one of Bob's rants). But I reread it and noticed you didn't answer the question. QUESTION: Deez wants to know will a high voltage HU make an audible difference: ANSWER: Brandonb: Nope Me: Tried both kind, didn't hear a difference. You: Theoretically blah blah noise floor at -10dBm vs. +4dBm dBu, dBV, DVD, VCR, ESPN blah blah blah.... Will Deez hear a difference, Matt? Yes or no? Now I'm starting to wonder if Howdy has jacked your account, or if you're just being intentionally obstinate? Got a touch of the PMS? I answered his question in my post: it CAN make a difference IF he uses other downstream equipment (crossover or amp) that can accept the hotter signal. I answered that RIGHT AT THE TOP and then went on to explain WHY that is. Whether Deez will actually hear a difference, nobody here can say. I don't know what the rest of the his system is like, if he has shyte speakers, or if he's tone-deaf. He might drop tens of thousands into a system and not be able to hear the difference between that an a stock AM radio. |
#15
Posted to rec.audio.car
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RCA Output voltage
MOSFET wrote:
So your answer is "it might, or it might not but I'm going to pick apart everything MOSFET said instead of giving you a straight answer". Okay, so how AM I supposed to give a straight answer as to whether or not someone else will hear a difference in his system? If I say "yes he will" and he's tone deaf, then he'll come back saying I'm a liar... if I say "no he won't" then he may go and upgrade anyway, find out he does hear a difference, and say I'm a liar. The only straight answer I, you, or anyone else can give to that question is, "he might." You are TRULY effecting my enjoyment of this newsgroup and I'm considering putting you on my blocked list (though most of your posts are intelligent and insightful so I don't want to). Go ahead, I'll try not to lose any sleep over it. But listen to me, PLEASE. Why don't you put me on your blocked list. I'm dead serious. Obviously there's something that bugs you about my posts because you nitpick nearly every one. PLEASE PUT ME ON YOUR BLOCKED LIST! How is adding more detail and expanding on things "nitpicking"? |
#16
Posted to rec.audio.car
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RCA Output voltage
MOSFET wrote:
You really should reread that post of yours and ask yourself "do I REALLY expect the OP to understand all of this?" Just as I can't know how good his hearing is, I don't know what his level of education or understanding is. So I explain things the best *I* can; I'm not an instructor. If he or someone else gains some useful knowledge from it, then good. If not, I'm only wasting my own time. Again, reread that post of yours. THINK about the original poster (who he is, how old he might be, etc.). Remember what we are here for, to HELP people. If that is your goal (as it is mine), you are tripping over your ego. Whatever. Just **** off and block me, and we'll both be happier. |
#17
Posted to rec.audio.car
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RCA Output voltage
Just **** off
Well, OK, Matt. Thank you for taking the time to respond to my concerns regarding this OBVIOUS tension between us (nitpicking nearly every one of my posts). As always, your responses are intelligent and thoughtful. MOSFET |
#18
Posted to rec.audio.car
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RCA Output voltage
How is adding more detail and expanding on things "nitpicking"?
I already gave you an example at the beginning of this thread: "Noise immunity" vs. "covering up". Frankly, "covering up" is a much better term because "immunity" implies eradication of noise. Like if you are given a vaccine against a particular disease, you are immune to it's effects. If you are exposed to the disease (in this case "noise"), an immunity would imply it would have absolutely no effect on you (like immunization against small pox implies if you are exposed to the smallpox virus, it will have absolutely no effect). This IS NOT a good analogy to what we are talking about with noise. If you have a sever ground-loop problem, a high-voltage pre-amp does not give you "immunity" against ground loop noise. Covering-up is a MUCH BETTER analogy (though perhaps not perfect) than "immunity". THIS MATT, IS THE KIND OF NITPICKING I'M TALKING ABOUT. BLOCK ME OR LEAVE MY POSTS ALONE (unless, of course, I get something horribly wrong like your advice about there being no such thing as a pre-amp for an iRiver you gave that guy). Thank you, Nick |
#19
Posted to rec.audio.car
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RCA Output voltage
MOSFET wrote:
THIS MATT, IS THE KIND OF NITPICKING I'M TALKING ABOUT. You're the one who's nit-picking now... BLOCK ME OR LEAVE MY POSTS ALONE My, don't you think highly of yourself. I'm not here to nit-pick your posts. I'm here to offer advice to ANYONE who asks, and to engage in semi-intelligent discussions relating to car audio. If that means correcting, adding to, expanding on, agreeing with, on ****ting on your posts, I'll do so. If that means correcting, adding to, expanding on, agreeing with, or ****ting on ANYONE ELSE'S posts, I'll do so. Don't take everything so personally, it's NOT all about Nick. My posts obviously upset you, so tell ya what, YOU block ME, and you'll have a happier life. |
#20
Posted to rec.audio.car
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RCA Output voltage
Don't take everything so personally, it's NOT all about Nick.
Good point. You do this annoying nitpicking thing to everyone. Again, before you start typing, ask yourself these questions: "Is this relevant to the OP's question? Is this REALLY going to help him? Does this FUNDAMENTALLY change the advice I am critiquing (if you are critiquing someone else's advice)? Or is this just a way to prove how smart I am?". You see, Matt, I have noticed that when it comes to some (not all, of course) of your posts, the answer to these questions is "no". Because you're right, you do this to a lot of people and I imagine it's annoying to them as well. Nick |
#21
Posted to rec.audio.car
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RCA Output voltage
MOSFET wrote:
Don't take everything so personally, it's NOT all about Nick. Good point. You do this annoying nitpicking thing to everyone. Again, before you start typing, ask yourself these questions: "Is this relevant to the OP's question? Is this REALLY going to help him? Does this FUNDAMENTALLY change the advice I am critiquing (if you are critiquing someone else's advice)?" Kinda depends on the OP. You assume everyone you respond to is a brain-dead moron and deserves a simple one-dimensional response. I assume they might have a hlaf a clue to start with, and learning a little more about how things work might actually help them in the future. I also try to remember that OTHER people besides to OP will be reading the thread, and that someone else might also be able to benefit from a little more knowledge. |
#22
Posted to rec.audio.car
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RCA Output voltage
gee it's just like roe all over again, which is why i left. really where you see the pre-out voltage at work is in the amps gains. say you have a deck at 2v you would set the gain maybe 2/3 of they way up (with a dmm of course) and with and 8v deck (like my eclipse) you would have to turn the gain up say 1/3 of the way. this keeps your amp from working as hard. i've used decks with 8v preouts all the way down to a 1 volt preout and can tell you there is a huge difference in the gain setting and sq. just my 2 cents and really noone even needs to listen to that but there it is. -- almond |
#23
Posted to rec.audio.car
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RCA Output voltage
almond wrote:
really where you see the pre-out voltage at work is in the amps gains. say you have a deck at 2v you would set the gain maybe 2/3 of they way up (with a dmm of course) and with and 8v deck (like my eclipse) you would have to turn the gain up say 1/3 of the way. this keeps your amp from working as hard. Well, this'll drive Nick crazy, but it's nitpick time again: The output voltage of your deck in this instance make no difference whatsoever to "how hard the amp works". Your deck is pushing out higher voltage, and your gain control is dialing it back down. In the end, it makes no difference to the amp. For easy calculation, let's assume your deck puts out 2V and you run the gain at full. The preamp section of the amp is getting up to a full 2V (fluctuating with the signal, of course). Now you use a deck that outputs 6V. In order to get the same output level, you have to turn the gain down to 1/3 (this is also assuming a linear input, for the sake of easy calculation). So now you're back down to a 2V signal coming out of the gain controls. i've used decks with 8v preouts all the way down to a 1 volt preout and can tell you there is a huge difference in the gain setting and sq. just my 2 cents and really noone even needs to listen to that but there it is. There's going to be a difference in the gain controls, for sure, but differences in sound quality are more likely due to many other factors besides just output voltage. Any deck that outputs 8V is NOT going to be a "cheap" deck, to begin with, and will inherently sound better than some electronics-superstore brand deck with 1V output. |
#24
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RCA Output voltage
Well, this'll drive Nick crazy, but it's nitpick time again:
The output voltage of your deck in this instance make no difference whatsoever to "how hard the amp works". Good point. And no, I don't consider this nitpicking at all........because it wasn't my post (JUST KIDDING). That was an important clarification: Pre-amp voltage makes no difference regarding how hard your amp works. MOSFET |
#25
Posted to rec.audio.car
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RCA Output voltage
yeah that sounds right now that i think of it. if your amp out put voltage is 50v it's doesn't matter really what the input voltage is your just going to set the gain to 50v. -- almond |
#26
Posted to rec.audio.car
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RCA Output voltage
i told you all yes..it make a difference.. but 5v is all ill try on most
amps made in the past....8v? good luck with that...lol can you kids understand???? 2v-3v. laughssssss |
#27
Posted to rec.audio.car
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RCA Output voltage
i'm running a niche audio na6000d it'll run at 8 volts in. -- almond |
#28
Posted to rec.audio.car
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RCA Output voltage
well almond ok just so you know. i got afew amps from yrs past.that cant
take above 5v. |
#29
Posted to rec.audio.car
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RCA Output voltage
i realize that, and yeah if your amp can't handle an 8 volt input then it's useless to have it. -- almond |
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