Finally dissected OE amp
12-01-2004, 05:17 PM
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Finally dissected OE amp
I finally remembered to pull apart the OE amp.
Looks like it uses two 4-channel output amp ICs. They look like the same OP IC's that would be inside a "high-power" head unit. There are 8 channels total coming out. The amp has good input filtering and wide traces for the IC outputs, but it is not a hi-fi design.
Two of the output channels have 2 uF caps in series which would act as first order gradual high-pass filters. These have to go to the two tweeters.
There is a signal processing duaghterboard that plugs into the main board with two 8-pin sockets. On this board are 5 JRC 3121 IC's, and four IC's from JRC which seem identical and which seem to be in signal pairs, but which I can't read the PN's for. (JRC used to be Japan Radio, and makes lots of audio IC's for various needs.)
I think the 3121's are op-amps being used in filters, and the four others might be too. I suspect that the four mystery IC's might be infrasonic low-pass filters on the 4 inputs, keeping damaging HF sginals and noise out, and the five others are F door high-pass, R door high-pass, and rear deck summed mono low-pass filters. That would leave the tweeters with caps as their only filters. It's also possible that they paralleled the outputs of the F door high-pass filter to the F mid and F tweet outputs so that low bass would be actively filtered out of the tweeter ahead of the amp input... in fact, I'd bet on it.
They probably saved about a quarter by using the two 2 uF caps in a crappy first-order filter instead of the two more op-amps in a better second-order filter...: )
Maybe someday I'll work on another TSX and connect my audio analyzer to the OE amp outputs with a pink noise disc loaded and find out what the xover points really are...
Looks like it uses two 4-channel output amp ICs. They look like the same OP IC's that would be inside a "high-power" head unit. There are 8 channels total coming out. The amp has good input filtering and wide traces for the IC outputs, but it is not a hi-fi design.
Two of the output channels have 2 uF caps in series which would act as first order gradual high-pass filters. These have to go to the two tweeters.
There is a signal processing duaghterboard that plugs into the main board with two 8-pin sockets. On this board are 5 JRC 3121 IC's, and four IC's from JRC which seem identical and which seem to be in signal pairs, but which I can't read the PN's for. (JRC used to be Japan Radio, and makes lots of audio IC's for various needs.)
I think the 3121's are op-amps being used in filters, and the four others might be too. I suspect that the four mystery IC's might be infrasonic low-pass filters on the 4 inputs, keeping damaging HF sginals and noise out, and the five others are F door high-pass, R door high-pass, and rear deck summed mono low-pass filters. That would leave the tweeters with caps as their only filters. It's also possible that they paralleled the outputs of the F door high-pass filter to the F mid and F tweet outputs so that low bass would be actively filtered out of the tweeter ahead of the amp input... in fact, I'd bet on it.
They probably saved about a quarter by using the two 2 uF caps in a crappy first-order filter instead of the two more op-amps in a better second-order filter...: )
Maybe someday I'll work on another TSX and connect my audio analyzer to the OE amp outputs with a pink noise disc loaded and find out what the xover points really are...
12-02-2004, 02:12 PM
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Thanks : ) Sorry, lemme explain better.
Any audio amp has a certain amount of power that it can generate, with a certain amount of distortion, when playing a given set of notes (the frequency response).
The standard set of notes is 20 Hz to 20,000 Hz. That's the "full range" of audio.
Speakers sound better when you filter out the notes that the speaker can't play well (that's called a "crossover filter" or just "crossover").
If you do that after the amplifier, on the speaker wire, you are doing it with "passive" crossover filters. These are used inside most big home speakers. You only need two amp channels, L and R, so it's cheaper from an amp perspective, but passive crossovers have drawbacks. One is that many crossover filters use big heavy coils of wire, called inductors. Another is that all of them sap some watts (called "insertion loss").
If you filter the sound before the amplifier with an "active" or "electronic" crossover, you need one set of amp channels for each set of speaker drivers (two for your tweeters, two for your mids, etc.) More expensive, but smaller, and the sound is better.
If you take an amp that has 10 watts at that "full-range" set of notes, and you narrow the set of notes drastically, you can increase the amount of power and decrease the amount of distortion from the amp, even before the speaker improvement comes into play! Like if your mids are only playing from 80 Hz and up, you just took out the lowest two octaves of bass, which are the most demanding for both a speaker and from an amplifier. You would have just increased your power to those speakers, and decreased their distortion. They should sound better (ignoring the possibility that your system design is jacked up).
Low notes are harder to play than midrange notes. If you use an "electronic" or "active" crossover, like the TSX amp does on the woofs and the mids, then you are preventing the mid amp from even seeing those low notes. If the amp doesn't see them when they happen, its mid power goes up, and its mid and high distortion goes down.
For the woofers, the power might go up slightly when you use an active filter before the amp, but also the parts that filter out mids and highs after an amp are big wire coils that are expensive and heavy (and sap watts from the amp anyway). Using the "electronic" filter instead of the "passive" filter that goes on the speaker wire saves weight, size, and cost.
So the TSX amp has 8 channels, and electronically takes the highs out of the 6x9 woofer channels, and the bass out of all the rest. The designer COULD have used an active crossover filter to take the mids out of the tweeters, but chose not to. If they had, the tweeters could have had midrange filtered out at a steeper filter rate, and at loud volumes, loud midrange would not have bothered the tweeters as much as reports seem to indicate.
Some people blow the tweets repeatedly. I think that the designer using a second-order active crossover on the tweeters would have prevented most of these failures, and made them sound much better at higher volumes.
Any audio amp has a certain amount of power that it can generate, with a certain amount of distortion, when playing a given set of notes (the frequency response).
The standard set of notes is 20 Hz to 20,000 Hz. That's the "full range" of audio.
Speakers sound better when you filter out the notes that the speaker can't play well (that's called a "crossover filter" or just "crossover").
If you do that after the amplifier, on the speaker wire, you are doing it with "passive" crossover filters. These are used inside most big home speakers. You only need two amp channels, L and R, so it's cheaper from an amp perspective, but passive crossovers have drawbacks. One is that many crossover filters use big heavy coils of wire, called inductors. Another is that all of them sap some watts (called "insertion loss").
If you filter the sound before the amplifier with an "active" or "electronic" crossover, you need one set of amp channels for each set of speaker drivers (two for your tweeters, two for your mids, etc.) More expensive, but smaller, and the sound is better.
If you take an amp that has 10 watts at that "full-range" set of notes, and you narrow the set of notes drastically, you can increase the amount of power and decrease the amount of distortion from the amp, even before the speaker improvement comes into play! Like if your mids are only playing from 80 Hz and up, you just took out the lowest two octaves of bass, which are the most demanding for both a speaker and from an amplifier. You would have just increased your power to those speakers, and decreased their distortion. They should sound better (ignoring the possibility that your system design is jacked up).
Low notes are harder to play than midrange notes. If you use an "electronic" or "active" crossover, like the TSX amp does on the woofs and the mids, then you are preventing the mid amp from even seeing those low notes. If the amp doesn't see them when they happen, its mid power goes up, and its mid and high distortion goes down.
For the woofers, the power might go up slightly when you use an active filter before the amp, but also the parts that filter out mids and highs after an amp are big wire coils that are expensive and heavy (and sap watts from the amp anyway). Using the "electronic" filter instead of the "passive" filter that goes on the speaker wire saves weight, size, and cost.
So the TSX amp has 8 channels, and electronically takes the highs out of the 6x9 woofer channels, and the bass out of all the rest. The designer COULD have used an active crossover filter to take the mids out of the tweeters, but chose not to. If they had, the tweeters could have had midrange filtered out at a steeper filter rate, and at loud volumes, loud midrange would not have bothered the tweeters as much as reports seem to indicate.
Some people blow the tweets repeatedly. I think that the designer using a second-order active crossover on the tweeters would have prevented most of these failures, and made them sound much better at higher volumes.
12-02-2004, 04:11 PM
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Great explanation dude!
Hey, I remember you saying you might be opening a business that will prevent you from coming to this forum as much. You're NOT still doing that, right?!
Hey, I remember you saying you might be opening a business that will prevent you from coming to this forum as much. You're NOT still doing that, right?!
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12-02-2004, 09:42 PM
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Originally Posted by elduderino
Thanks : ) Sorry, lemme explain better.
Any audio amp has a certain amount of power that it can generate, with a certain amount of distortion, when playing a given set of notes (the frequency response).
The standard set of notes is 20 Hz to 20,000 Hz. That's the "full range" of audio.
Speakers sound better when you filter out the notes that the speaker can't play well (that's called a "crossover filter" or just "crossover").
If you do that after the amplifier, on the speaker wire, you are doing it with "passive" crossover filters. These are used inside most big home speakers. You only need two amp channels, L and R, so it's cheaper from an amp perspective, but passive crossovers have drawbacks. One is that many crossover filters use big heavy coils of wire, called inductors. Another is that all of them sap some watts (called "insertion loss").
If you filter the sound before the amplifier with an "active" or "electronic" crossover, you need one set of amp channels for each set of speaker drivers (two for your tweeters, two for your mids, etc.) More expensive, but smaller, and the sound is better.
If you take an amp that has 10 watts at that "full-range" set of notes, and you narrow the set of notes drastically, you can increase the amount of power and decrease the amount of distortion from the amp, even before the speaker improvement comes into play! Like if your mids are only playing from 80 Hz and up, you just took out the lowest two octaves of bass, which are the most demanding for both a speaker and from an amplifier. You would have just increased your power to those speakers, and decreased their distortion. They should sound better (ignoring the possibility that your system design is jacked up).
Low notes are harder to play than midrange notes. If you use an "electronic" or "active" crossover, like the TSX amp does on the woofs and the mids, then you are preventing the mid amp from even seeing those low notes. If the amp doesn't see them when they happen, its mid power goes up, and its mid and high distortion goes down.
For the woofers, the power might go up slightly when you use an active filter before the amp, but also the parts that filter out mids and highs after an amp are big wire coils that are expensive and heavy (and sap watts from the amp anyway). Using the "electronic" filter instead of the "passive" filter that goes on the speaker wire saves weight, size, and cost.
So the TSX amp has 8 channels, and electronically takes the highs out of the 6x9 woofer channels, and the bass out of all the rest. The designer COULD have used an active crossover filter to take the mids out of the tweeters, but chose not to. If they had, the tweeters could have had midrange filtered out at a steeper filter rate, and at loud volumes, loud midrange would not have bothered the tweeters as much as reports seem to indicate.
Some people blow the tweets repeatedly. I think that the designer using a second-order active crossover on the tweeters would have prevented most of these failures, and made them sound much better at higher volumes.
Any audio amp has a certain amount of power that it can generate, with a certain amount of distortion, when playing a given set of notes (the frequency response).
The standard set of notes is 20 Hz to 20,000 Hz. That's the "full range" of audio.
Speakers sound better when you filter out the notes that the speaker can't play well (that's called a "crossover filter" or just "crossover").
If you do that after the amplifier, on the speaker wire, you are doing it with "passive" crossover filters. These are used inside most big home speakers. You only need two amp channels, L and R, so it's cheaper from an amp perspective, but passive crossovers have drawbacks. One is that many crossover filters use big heavy coils of wire, called inductors. Another is that all of them sap some watts (called "insertion loss").
If you filter the sound before the amplifier with an "active" or "electronic" crossover, you need one set of amp channels for each set of speaker drivers (two for your tweeters, two for your mids, etc.) More expensive, but smaller, and the sound is better.
If you take an amp that has 10 watts at that "full-range" set of notes, and you narrow the set of notes drastically, you can increase the amount of power and decrease the amount of distortion from the amp, even before the speaker improvement comes into play! Like if your mids are only playing from 80 Hz and up, you just took out the lowest two octaves of bass, which are the most demanding for both a speaker and from an amplifier. You would have just increased your power to those speakers, and decreased their distortion. They should sound better (ignoring the possibility that your system design is jacked up).
Low notes are harder to play than midrange notes. If you use an "electronic" or "active" crossover, like the TSX amp does on the woofs and the mids, then you are preventing the mid amp from even seeing those low notes. If the amp doesn't see them when they happen, its mid power goes up, and its mid and high distortion goes down.
For the woofers, the power might go up slightly when you use an active filter before the amp, but also the parts that filter out mids and highs after an amp are big wire coils that are expensive and heavy (and sap watts from the amp anyway). Using the "electronic" filter instead of the "passive" filter that goes on the speaker wire saves weight, size, and cost.
So the TSX amp has 8 channels, and electronically takes the highs out of the 6x9 woofer channels, and the bass out of all the rest. The designer COULD have used an active crossover filter to take the mids out of the tweeters, but chose not to. If they had, the tweeters could have had midrange filtered out at a steeper filter rate, and at loud volumes, loud midrange would not have bothered the tweeters as much as reports seem to indicate.
Some people blow the tweets repeatedly. I think that the designer using a second-order active crossover on the tweeters would have prevented most of these failures, and made them sound much better at higher volumes.
please explain to this audience how you make an amplifier put out more watts when you run an electronic filter?
i agree that you would be able to delever more power to the speakers without the insertion losses inherent with passive filters.
but please tell me in your wisdom how you expect to get more power from an amplifier with an active filter.
you seriously need to take a basic AC electronics course or something because CLEARLY once again you don't know what the hell your talking about.
its so sad, you start off by giving some really good information then louse it all up by throwing in another .02 just for good measure by making somthing up.
so go ahead. im anxious to hear this new founded electronics fundamentals you have invented here.
12-03-2004, 12:38 AM
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No, you just want to argue.
Anyone who is interested can see this:
http://www.polkaudio.com/home/faqad/...cle=pwrratings
http://www.audiocontrol.com/techpapers/techpaper104.pdf
Anyone who is interested can see this:
http://www.polkaudio.com/home/faqad/...cle=pwrratings
http://www.audiocontrol.com/techpapers/techpaper104.pdf
12-03-2004, 09:37 AM
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Originally Posted by elduderino
No, you just want to argue.
Anyone who is interested can see this:
http://www.polkaudio.com/home/faqad/...cle=pwrratings
http://www.audiocontrol.com/techpapers/techpaper104.pdf
Anyone who is interested can see this:
http://www.polkaudio.com/home/faqad/...cle=pwrratings
http://www.audiocontrol.com/techpapers/techpaper104.pdf
no where in any of the links does it say anything about limiting an amplifiers bandwidth increases power.
what is does say and what is true is that by running separate amplifiers you can run different wattages to separate woofers and tweeters to match their respective db levels. this is very true, the reason a woofer "robs power" which is a loose term is because when the amplifier clips thats the end of the power it can delever to the speakers.
at this point of clipping the whole signal will get clipped not because the sub has robbed anything but simply because both woofer and tweeter are getting the same number of WATTS. the information to the tweeter is now clipped and at that point in time anything else connected to that amplifiers output channel will clip along with it.
it has nothing to do with the bandwidth, it has everything to do with the fact it takes more watts to make the same db with a woofer as opposed the tweeter, they have different sensitivity ratings.
they are saying that using a 60 watt amplifier to drive a woofer and 20 watt amp to drive a tweeter using an electronic xover will yield more clean and more efficient power. which is true because now you have 80 watts instead of 60 watts total output. does each speaker play any louder than it did before?
the woofer has the exact same db as it did before because it's still connected to a 60 watt amp. the tweeter has actually less watts going to it and therefore will not be sd loud as it was before. but now it's db is matched to the woofer.
additionally now if the woofer clips the tweeter remains unaffected because it has its own separate amp.
what they didnt mention is that you can do the exact same thing by installing a tweeter attenuation be it a resistor or an L-Pad to lower the output of the tweeter and just pick a bigger amplifier. you will accomplish nearly the same thing. you will still clip the signal of you over drive the amplifier but if you have more watts to begin with your chances of clipping that woofer or anything on that amplifier are far less. matching the tweeter is easy if you know what your doing.
what you may not realise is that this write up by audio control which is very good and accurate information is written to educate and promote the idea of using an electronic crossover to separate the signals used in a bi amplification system. audio control does in fact sell electronic xovers and probly sells more than most other manufacturers. it would not be bennificial to educate the public on the concept of using a passive crossover and tweeter attenuation to accomplish nearly the same thing because it would not be good for the promotion and sale of their products.
so in short:
Q. does a bi amplified system have more power than a single amplifier?
A. it depends on how many watts you add. if you started with 60 and add 20 then yes. if you started with a 60 and reconfigured it to have 50 and 10 watts then no but you would still gain the bennifit of 1 amp not causing the other amp to clip during intense musical passages.
based on the fact that woofers do require more power than tweeters do to attain the same db level. woofers typically have far less sensitivity than tweeters do.
therefore if you want them to play at the same db level you need 2 separate amplifiers to match their respective sensitivity ratings.
as a result you may preceive that there is more output. as you turn up the volume the effects of a clipped signal to the mids and highs running separate amplifiers are reduced. thoes speakers amplifiers wont see the clipped bass signal and therefore wont clip or distort during thoes passages. it is because they arent being asked to reproduce the bass frequencies which are typically recorded with a higher db level to compensate for the efficiency losses typical with woofers.
i think what you should have said in your post is that using an active xover will allow you to send more power to a speaker such as the midbass speakers of the TSX if you eliminate the low bass notes they are incapable of reproducing.
doing so will make more efficient use of the frequencies they can reproduce.
but i am putting words in your mouth. i dont know if that was the point you were trying to make or not.
so after all this Elduderino, you still have not explained to us how an amplifier makes more power by reducing it's bandwidth or in other words using an active crossover will make an amplifier make more power.
you cannot make power with what you never had to begin with. i keep telling you that the laws of physics don't change just for you. they are the same for everyone.
just because you come in here and say it doesnt make it true.
i think what you hoped would happen is that i and the rest of us would read what you provided (with a smirk on your face).
that with the information we would be shown you were correct in your statement that you can increase an amplifiers power by using an active xover.
unfortunatly the information you provided if you had actually taken the time to READ it and fully understand it. clearly shows that once again you don't know what your talking about.
either you never read it to begin with, or your comprehention reading skills needs a little more practice.
here is a tip for you, how about you just stick to the things you actually know, understand and prove with actual facts?
when you type information for the board stick to the simple stuff. you seem to have a pretty good general understanding of sound in general. i can tell you have a pretty good inderstanding of that. but i think you need to stay away from trying to educate any of us with your knowledge of electronics. especially anything to do with AC. this seems to be the area you dont fully understand and how it relates to sound.
i know you are the "VP of electricity" and since you have that in your name we should all Bow in your presence. but i think it has gone a little too far to your head.
maybe you should change it to "audio tinker guy" because you have a long way to go to be the VP of anything related to electricity.
ive been studying it since i was about 7 years old. ( i am 34 now) and i still dont think i come close to deserving that title yet.
i am sorry if you think i am being hard on you. i just have a hard time sitting here reading things i know to be totally false. most of what you write is great. and helpfull to a lot of people. i wish i had the time to visit the board every day like you do. but unfortunatly i have a business to run (or fortunatly depends on how you look at it) and as a result i cannot be here every day writing stuff about audio and electronics. i dont have time to answer everyones questions and show everyone how much i know on the subject.
i can tell by your responces to compliments you get from people that you really enjoy the fact that people look up to you because of your apparent knowledge. however i just wish the knowledge you give the impression of having was actually factual on all the posts you reply to.
if you will notice when i give information to people it's always accurate or i dont give it.
if i dont know ill tell you so, or ill say "i suspect this is the case".
do i think i know everything? Hell NO! not even close. but i know when i am right and i know when i dont know.
you need to figure out that for yourself.
Edit, i just thought of somthing, maybe you should stay away from your little write ups. thoes seem to bite you in the ass the most. usually when you answer threads simple answers you give to simple questions seems to be the area where your information is mostly accurate. if i were you i would stick to that.
12-03-2004, 11:29 AM
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I feel no bite marks in my ass, thank you very much. I am sorry that you feel so angry, and I hope you get that straightened out soon. (Hint: It's not about me...)
Apparently I mis-stated something that this guy is upset about. There is not an electronics theory rule that says that narrowing the signal increases the power out. That line I wrote was an error - there is no RULE.
Limiting the audio bandwidth coming into an amp, and bi-amping, have numerous positive effects that can make your system sound more powerful, some of which have been mentioned and some of which have not, but there is not a rule of amplifier design theory that says what I said. Theoretically, with a good amplifier, this statement is not true. When using lower-end amps, or using low-current IC amps like those in a HU or in the TSX amplifier, you would expect some increase in output power /decrease in distortion up to a certain limit when you limit the bandwidth and remove the LF notes that these amps don't play well - but it's not a global rule. Alpine used to have a pre-in input on some of their "high-power" HUs so that they could use the HP output of their electronic crossover on the IC amp insude the HU, and then it could play a decent set of F speakers loud without breaking up every time a bass note hit - but this was due to the amp specifically, not due to the concept globally.
Hopefully we've avoided anyone sinking time and money into some electronics project because of my goof in explaining things.
Now that 1500 ranting words have been posted about that... BM, if I were you, I'd save that unsolicited personal advice for your insurance customers.
Apparently I mis-stated something that this guy is upset about. There is not an electronics theory rule that says that narrowing the signal increases the power out. That line I wrote was an error - there is no RULE.
Limiting the audio bandwidth coming into an amp, and bi-amping, have numerous positive effects that can make your system sound more powerful, some of which have been mentioned and some of which have not, but there is not a rule of amplifier design theory that says what I said. Theoretically, with a good amplifier, this statement is not true. When using lower-end amps, or using low-current IC amps like those in a HU or in the TSX amplifier, you would expect some increase in output power /decrease in distortion up to a certain limit when you limit the bandwidth and remove the LF notes that these amps don't play well - but it's not a global rule. Alpine used to have a pre-in input on some of their "high-power" HUs so that they could use the HP output of their electronic crossover on the IC amp insude the HU, and then it could play a decent set of F speakers loud without breaking up every time a bass note hit - but this was due to the amp specifically, not due to the concept globally.
Hopefully we've avoided anyone sinking time and money into some electronics project because of my goof in explaining things.
Now that 1500 ranting words have been posted about that... BM, if I were you, I'd save that unsolicited personal advice for your insurance customers.
12-03-2004, 12:40 PM
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Originally Posted by Dan Martin
Whole lotta hostility in here.
Damn...that was one long post up there. It's so long I'm not even gonna try to read it...
Maybe I'll come back and read it during...my freetime..instead of when I should be working.... 
12-03-2004, 12:48 PM
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I'm sure it could be technically possible to modify the OE amp, but it seems to be a pointless process. You would need to get the service manual for the amplifier, puzzle out what you wanted to change, and then do some pretty good surface-mount soldering - all to try to get more power or a better xover design? I would think it would be much simpler and faster to replace the OE amp with an aftermarket.
The only caveat I will include here is that if someone wanted to use a pair of seperates like an MB Quart Premium or Reference which have bi-wiring inputs for the tweeter and the woofer (basically isolating the TW and WF xovers and requiring two sets of inputs), it is technically possible to use the Tweeter OP and the F Mid OP from the amp and run them both into the MBQ passive Xover. You would need to pull the Bi-wire jumper which on current MB Q crossovers is not labeled (someone else floated this question a few weeks ago - it's visually obvi).
The amp mod would be to pull the two circuit boards out and drop a solder bridge or a short piece of wire across the bottom of the two 2uF caps on the main board (the main board is through-hole, the daughterboard is SMT). This would remove the passive tweeter xover - leaving it in creates a weird and incorrect tweeter xover once you add this into the external xover topology.
Since the board sits on the bottom of the chassis, care would be required to avoid a short against the chassis, but that's the only mod that comes to mind... and I'm still not very optimistic about how a speaker would sound driven by this amp, through a second order xover with a big coil in it... those coils sap amp power, and this amp can't bear much insertion loss.
I would post pics sometime soon...I'll put a ruler in the pics. Think thick paperback.
If this was an amp with transistorized outputs and a real power supply, it would potentially be a candidate for mods, but then it would be more costly and then it wouldn't be OE anyway... : )
Transistor-output amps are better than IC amps in so many ways, and you aren't making that modification, that's for sure.
The only caveat I will include here is that if someone wanted to use a pair of seperates like an MB Quart Premium or Reference which have bi-wiring inputs for the tweeter and the woofer (basically isolating the TW and WF xovers and requiring two sets of inputs), it is technically possible to use the Tweeter OP and the F Mid OP from the amp and run them both into the MBQ passive Xover. You would need to pull the Bi-wire jumper which on current MB Q crossovers is not labeled (someone else floated this question a few weeks ago - it's visually obvi).
The amp mod would be to pull the two circuit boards out and drop a solder bridge or a short piece of wire across the bottom of the two 2uF caps on the main board (the main board is through-hole, the daughterboard is SMT). This would remove the passive tweeter xover - leaving it in creates a weird and incorrect tweeter xover once you add this into the external xover topology.
Since the board sits on the bottom of the chassis, care would be required to avoid a short against the chassis, but that's the only mod that comes to mind... and I'm still not very optimistic about how a speaker would sound driven by this amp, through a second order xover with a big coil in it... those coils sap amp power, and this amp can't bear much insertion loss.
I would post pics sometime soon...I'll put a ruler in the pics. Think thick paperback.
If this was an amp with transistorized outputs and a real power supply, it would potentially be a candidate for mods, but then it would be more costly and then it wouldn't be OE anyway... : )
Transistor-output amps are better than IC amps in so many ways, and you aren't making that modification, that's for sure.
12-03-2004, 01:59 PM
#18
Burning Brakes
Join Date: Apr 2002
Location: Colorado Springs, Colorado
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Originally Posted by elduderino
I feel no bite marks in my ass, thank you very much. I am sorry that you feel so angry, and I hope you get that straightened out soon. (Hint: It's not about me...)
so trust me, my only issue truly does lie specifically with what i stated. YOUR constant barrage of bad information and then unsuspecting people trying to learn are being infected with your false information.
when people read to learn they read non-fiction books. not science fiction.
get the idea? thats all im saying
thanks for admitting your fault. i know thats a tall order for you or at least has been in the past. its good to see that you realise it's ok to say your wrong sometimes.
aside from what you may think i have no hatred towards you. you have proven to be a valuable assett to this board and you do have a good wealth of information to share as well as apparently a lot more tim on your hands to share it than i do. all i have a problem with is when you share information to people that is simply false or made up. a slip up such as in this case i assume you would like us to belive can breed more false understanding of the subject matter.
as many unfounded rumors as there are in caraudio we dont need any more bad information floating around than we already have.
and finally you and i would never have come to arguing over things like this if you had not joined this board and within the first few days attacked me about that alternator question. when you saw you might be in the wrong you tried whatever you could to make it sound like you were really right all along and never admitted that in fact you didnt have the background to back up your theroy.
since then yes i have paid special attention to the things you say because you disrespected me in trying to call me out on what which you could not proove otherwise.
had this not happend i might have just messaged you privatly to alert you to your bad information. most people, after learning they are in error are happy to correct the error and move on. you seem to prefer to challenge me on it untill you either get sick of it and give up or twist what you say to sound right.
this thread is the first i have seen you admidt you said somthing that
A. wasnt true
B. cant be proven
C. was your understanding of the subject and you admitted you made an error.
12-03-2004, 09:19 PM
#22
You want me to break it?
Join Date: Sep 2003
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Now in all honesty I haven't read those links posted by eld, and I don't really feel like I know anything about you but I do know this - BassMechanic knows this crap backwards and forwards - just be careful when you argue audio with him... 
12-04-2004, 01:25 AM
#24
Burning Brakes
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Originally Posted by Gpump
Now in all honesty I haven't read those links posted by eld, and I don't really feel like I know anything about you but I do know this - BassMechanic knows this crap backwards and forwards - just be careful when you argue audio with him...
thanks Gpump. im not sure i even know who you are but i appreciate the
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