Pinky's Radios
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From: Columbia, MD
Originally posted by Barry WY Silver/Black '01
(Not measuring with "all channels driven") is a common place where head unit specs "cheat." They leave off the "all channels driven" and measure only 1 channel at a time which often gives a higher number. I've seen head units claming "30x4" which is meaningless but most people take it to mean that the head unit produces 30watts each into 4 channels. That's 120 watts from a head unit. No amp is 100% efficient so let us say it draws 150 watts to do this (80% efficiency which is still high). With a 12V power input, the head unit amp's power supply would be drawing 12.5 amps. I guarantee you that it is not easy to design a power supply that fits into a head unit leaving enough room for everything else (including the amp stages themselves) for any reasonable price that can deliver that kind of power.
(Not measuring with "all channels driven") is a common place where head unit specs "cheat." They leave off the "all channels driven" and measure only 1 channel at a time which often gives a higher number. I've seen head units claming "30x4" which is meaningless but most people take it to mean that the head unit produces 30watts each into 4 channels. That's 120 watts from a head unit. No amp is 100% efficient so let us say it draws 150 watts to do this (80% efficiency which is still high). With a 12V power input, the head unit amp's power supply would be drawing 12.5 amps. I guarantee you that it is not easy to design a power supply that fits into a head unit leaving enough room for everything else (including the amp stages themselves) for any reasonable price that can deliver that kind of power.
Tricky little bastards...Ordering electronic components is just as bad as playing in a minefield if you don't already know the tricks for that particular type of component...oh well, one more list of tricks to add to my bag...
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From: Sheridan
I thought you would like that, Dan.
I've just been listening loud enough (and fast enough--no ticket though) to make some conclusions. Also, I went back to my audio store and listenend back and forth between xr60p (the SEPARATE component version of xr600) and Alpine 6 x 9 speakers and with the Alpines as front and the xr60p as rear. I used the same head the store sold me. I assume they stuck decent wire in. The xr60p speakers were not "bi-amp" installed.
Also, I talked with customer tech support at Kenwood. Miguel, the Kenwood rep, seemed pretty knowledgable. He said the xr600 speakers are 4 ohm as a parallel powered pair or as separates. He said there's a coil and a capacitor in the wiring that effects this.
Miguel of Kenwood also said that the speaker wiring was not a limiting factor unless I went to power the speakers with a separate amp. He did recommend installing an amp, like Pinky said, to get the best, because 27 watts rms is underpowering these speakers. He pointed out that the speaker lead wires in Kenwood heads are 20 gauge. Does this sound possible?
He said I could get a benefit from powering the tweeters from the front speaker outputs and the woofer from rear speaker outputs IF the head has a cross-over built in to send high frequency forward and low frequency rearward.
Finally, Miguel suggested that my next step might be to add a powered subwoofer or a subwoofer and amplifier and let the sub handle the frequencies below 160 hz that are giving my head and speakers a problem. He strongly recommended mounting the sub somewhere in the cabin rather than in the trunk.
I tried to look at a pair of new xr600 speakers but the store was out. I was going to measure ohms too, but, again no test speakers.
Most important for me, I listened and listened and listened and played with head controls and listened some more. At moderate volumes--around town driving, I get very satisfying sound including bass with the head controls pretty flat or even with some bass boost. That's for a numeric volume setting of 15-20 out of 35 arbitrary units. At 80 mph, top down, windows down I get very satisfying sound at a volume setting of 25-30, but I have to dial out some of the bass to get rid of distortion. On the Alpine head I can do this three ways (1) bass tone control (which is variable in center frequency and curve shape); (2) high pass filter (which is variable in three steps in cut frequency 80, 120, 160; or by (3) switching out BBE which cuts bass even though that is not how the BBE web page describes what is going on. If I crank the sound up to 35 out of 35 arbitrary units, I can hear the highs clearly by cutting the bass more. That is much louder than I need for comfortable listening, even 80 mph, top down, windows down.
I'm going to listen more, post less, spend even less and make a decision after I've really gotten to know my current setup better.
I've just been listening loud enough (and fast enough--no ticket though) to make some conclusions. Also, I went back to my audio store and listenend back and forth between xr60p (the SEPARATE component version of xr600) and Alpine 6 x 9 speakers and with the Alpines as front and the xr60p as rear. I used the same head the store sold me. I assume they stuck decent wire in. The xr60p speakers were not "bi-amp" installed.
Also, I talked with customer tech support at Kenwood. Miguel, the Kenwood rep, seemed pretty knowledgable. He said the xr600 speakers are 4 ohm as a parallel powered pair or as separates. He said there's a coil and a capacitor in the wiring that effects this.
Miguel of Kenwood also said that the speaker wiring was not a limiting factor unless I went to power the speakers with a separate amp. He did recommend installing an amp, like Pinky said, to get the best, because 27 watts rms is underpowering these speakers. He pointed out that the speaker lead wires in Kenwood heads are 20 gauge. Does this sound possible?
He said I could get a benefit from powering the tweeters from the front speaker outputs and the woofer from rear speaker outputs IF the head has a cross-over built in to send high frequency forward and low frequency rearward.
Finally, Miguel suggested that my next step might be to add a powered subwoofer or a subwoofer and amplifier and let the sub handle the frequencies below 160 hz that are giving my head and speakers a problem. He strongly recommended mounting the sub somewhere in the cabin rather than in the trunk.
I tried to look at a pair of new xr600 speakers but the store was out. I was going to measure ohms too, but, again no test speakers.
Most important for me, I listened and listened and listened and played with head controls and listened some more. At moderate volumes--around town driving, I get very satisfying sound including bass with the head controls pretty flat or even with some bass boost. That's for a numeric volume setting of 15-20 out of 35 arbitrary units. At 80 mph, top down, windows down I get very satisfying sound at a volume setting of 25-30, but I have to dial out some of the bass to get rid of distortion. On the Alpine head I can do this three ways (1) bass tone control (which is variable in center frequency and curve shape); (2) high pass filter (which is variable in three steps in cut frequency 80, 120, 160; or by (3) switching out BBE which cuts bass even though that is not how the BBE web page describes what is going on. If I crank the sound up to 35 out of 35 arbitrary units, I can hear the highs clearly by cutting the bass more. That is much louder than I need for comfortable listening, even 80 mph, top down, windows down.
I'm going to listen more, post less, spend even less and make a decision after I've really gotten to know my current setup better.
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From: Warren
Just a note, the Kenwoods come with a built in crossover, which I am using. I just didn't want to run extra wires. I also used an adapter to the stock connectors. Note that the Kenwoods do NOT require cutting the basket.
No on the buttons, couldn't the same button send both signals? If in CD mode the track change would be understood, in radio mode the channel change. In either case, wouldn't the radio ignore the extra signal?
David
No on the buttons, couldn't the same button send both signals? If in CD mode the track change would be understood, in radio mode the channel change. In either case, wouldn't the radio ignore the extra signal?
David
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From: San Jose
David NJ:
What do you mean by "built" in crossover. And when you say you are using it, if its built in don't you pretty much have to use it?
The reason Im asking is I didn't get any crossovers with my speakers.. . Also, the box doesn't show any other crossover.
It is possible they changed it from when I got mine to when you got yours...
-- Robert
What do you mean by "built" in crossover. And when you say you are using it, if its built in don't you pretty much have to use it?
The reason Im asking is I didn't get any crossovers with my speakers.. . Also, the box doesn't show any other crossover.
It is possible they changed it from when I got mine to when you got yours...
-- Robert
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