Old school amp
06-08-2006, 11:24 AM
#91
0 Watt CAFz'r
Join Date: Jun 2006
Posts: 34
Originally Posted by veeman
Remember, according to you guys, it's manufacturer's word as to specs etc... and should be relied on. See link below:
http://www.rockfordfosgate.com/scripts/rightnow.cfg/php.exe/enduser/std_adp.php?p_faqid=418
http://www.rockfordfosgate.com/scripts/rightnow.cfg/php.exe/enduser/std_adp.php?p_faqid=418
Yeah but Rockford amps are still expensive.... heck you can buy a $20,000 version if I'm not mistaken.
Also, it doesn't list, damping at rated power. Doesn't have how many channels drivin at rated power. Doesn't say if it's rated with a 1kHz test pulse or a 20Hz-20kHz test pulse. Very, very vague comparisions. A 50watts with 20hz-20kHz may be over 100watts with a 1kHz test pulse. Where is that info or was it conveniantly left out? Is the sound output as flat as before? You can't judge by wattage alone...
Not to mention Rockford isn't one of the greatest of the erra. They were good but IMO Orion, Blade, Zapco, PPI were much, much better. Nowhere did you see 1%THD and 14.4 volt ratings with a Zapco, etc.. More like 0.04THD at rated 12v power.
06-08-2006, 11:31 AM
#92
1000 Watt CAFz'r
Join Date: Aug 2004
Posts: 1,267
Originally Posted by Faststang
Guys I know the db sounds outrageous but case and point. I mimiked the enclosure of a Paradigm PS 1000 Home theater enclosure x2. Each PS 1000 will shake your neghbours house... don't believe me goto any quality home audio theater dealer and crank one... no.... two.. all the way up and tell me that isn't crazy db's in your HOUSE let alone a car.
Not only that but they were rated to 100 watts 1% THD and are 10" subs. NOW I'm throwing in 900watts and to dual enclosures.
As for the amps being sold I think it's all demographics... I mean you goto comps and you see people running db drags not SQ. Companies pump out high wattage 10% class D amps cheap because kids buy them. Lets face it, few people, if any, care about SQ in their cars. They goto "westcoast customs" and they throw in thier cr@p audiobahn stuff. Companies don't pump out class A (real audiophile stuff) or an expensive A/B amplifier because db people want db's not SQ and few people are running or care about real SQ anymore.
Also 1% THD on an oscilliscop is very obvious. The clipping effect is what damages speakers. Class D's do clip and same with AB during the cycle change. The only amp that ANY home audiophile user will take is a class A. AB running a close second.
You don't think 1% is a big deal... get into SQ home audio and tell them they have to run 1% THD. They would take your head off.
EDIT: Found this on www.hometheaterforum.com real quick
" ..look for the lowest THD ratings and true wattage at 8 ohms.You want THD at .08 or less...
As a side note. Also remember the watt rating on an amp isn't always an accurate one. Things to watch for are amps that give their rating at 1khz instead of from 20hz-20khz. Amps that give THD numbers higher than 0.1 in their power rating. Amps that don't specifiy all channels were being driven when this power output rating was obtained. Amps that rate into 6ohms but say not to drive 6ohm speakers. So as an example take these two specs:
1) 110W at 1khz, with 0.7%THD into 6ohms (on the front of the box they also claim 110Wx5 and in the manual say not to drive 6ohm speaker with it)
2) 70Wx5 (all channels driven) from 20hz-20khz, with 0.08THD into 8ohms (manual says you can drive 6ohm speakers)"
Not only that but they were rated to 100 watts 1% THD and are 10" subs. NOW I'm throwing in 900watts and to dual enclosures.
As for the amps being sold I think it's all demographics... I mean you goto comps and you see people running db drags not SQ. Companies pump out high wattage 10% class D amps cheap because kids buy them. Lets face it, few people, if any, care about SQ in their cars. They goto "westcoast customs" and they throw in thier cr@p audiobahn stuff. Companies don't pump out class A (real audiophile stuff) or an expensive A/B amplifier because db people want db's not SQ and few people are running or care about real SQ anymore.
Also 1% THD on an oscilliscop is very obvious. The clipping effect is what damages speakers. Class D's do clip and same with AB during the cycle change. The only amp that ANY home audiophile user will take is a class A. AB running a close second.
You don't think 1% is a big deal... get into SQ home audio and tell them they have to run 1% THD. They would take your head off.
EDIT: Found this on www.hometheaterforum.com real quick
" ..look for the lowest THD ratings and true wattage at 8 ohms.You want THD at .08 or less...
As a side note. Also remember the watt rating on an amp isn't always an accurate one. Things to watch for are amps that give their rating at 1khz instead of from 20hz-20khz. Amps that give THD numbers higher than 0.1 in their power rating. Amps that don't specifiy all channels were being driven when this power output rating was obtained. Amps that rate into 6ohms but say not to drive 6ohm speakers. So as an example take these two specs:
1) 110W at 1khz, with 0.7%THD into 6ohms (on the front of the box they also claim 110Wx5 and in the manual say not to drive 6ohm speaker with it)
2) 70Wx5 (all channels driven) from 20hz-20khz, with 0.08THD into 8ohms (manual says you can drive 6ohm speakers)"
06-08-2006, 11:34 AM
#93
0 Watt CAFz'r
Join Date: Jun 2006
Posts: 34
Originally Posted by theboy
Why does the Servo 15(Paradigms top end subwoofer)use a class D amp?
edit- for example listening to a female singing. Words can get distorted, not coherant. Nobody can distinguish the difference with bass it's just BOOM BOOM to the human ear.
Also, even rockford publishing that page is a testament to how many people realise there is a difference in the new stuff.
Last edited by Faststang; 06-08-2006 at 11:39 AM.
06-08-2006, 11:38 AM
#94
^^because they want to get with the times, and realize that new technology is much better overall with respect to human interaction. Those distortion numbers, s/n ratios and damping factors etc...have all been proven by scientific double blind tests to be undetectable by any human with ears. I think Richard Clark's challenge is still standing.
06-08-2006, 12:11 PM
#95
Originally Posted by veeman
^^because they want to get with the times, and realize that new technology is much better overall with respect to human interaction. Those distortion numbers, s/n ratios and damping factors etc...have all been proven by scientific double blind tests to be undetectable by any human with ears. I think Richard Clark's challenge is still standing.
It's totally up to you if you want to damage your speaker slowly. I could care less if you turn your gains up all the way and get 50% distortion, if that's how you wanna do it go ahead. I just won't, don't matter how many figures you throw at me about class D. I could care less. Been there done that and it's not something i'm going back to.
Sure, maybe you can't hear the distortion now but double blind tests have confirmed that any human with ears can tell a blown speaker from a good speaker.
06-08-2006, 12:11 PM
#96
0 Watt CAFz'r
Join Date: Jun 2006
Posts: 34
Originally Posted by veeman
^^because they want to get with the times, and realize that new technology is much better overall with respect to human interaction. Those distortion numbers, s/n ratios and damping factors etc...have all been proven by scientific double blind tests to be undetectable by any human with ears. I think Richard Clark's challenge is still standing.
Fine I'll present you with a challenge. Find ANY and I mean ANY high end HOME audio manufacture that uses a class D amplifier to power thier main speakers.
You won't.. Paradigm uses class D as a sub amp because the human ear can't distinguish BASS. Since when does bass become non-coherant? I could run 10% THD and not distinguish the bass difference... use 10% on a female voice and you will hear the difference.
Infact I think you will find that all NEW GEN high end $10,000 plus home entertainment setups used OPTICAL CLASS A or AB amplifiers....
HMMMMMM sounds ALOT like my OLD SCHOOL BLADE GRENADE!!!!!! Find me an optical class A car audio amp these days.... an even better challenge!
Last edited by Faststang; 06-08-2006 at 12:28 PM.
06-08-2006, 12:12 PM
#97
0 Watt CAFz'r
Join Date: Jun 2006
Posts: 34
Originally Posted by 03rejo
So how'd we get to what we can hear? It's all about what the sub can hear! Just because a double-cheeseburger tastes good doesn't mean it is good for you. Same with a speaker, just because you can't hear under 5% distortion doesn't mean the sub doesn't feel it!
:
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This is very valid also.
06-08-2006, 12:53 PM
#99
0 Watt CAFz'r
Join Date: Jun 2006
Posts: 34
Originally Posted by veeman
^^because they want to get with the times, and realize that new technology is much better overall with respect to human interaction. Those distortion numbers, s/n ratios and damping factors etc...have all been proven by scientific double blind tests to be undetectable by any human with ears. I think Richard Clark's challenge is still standing.
Had a good laugh.. First off the Paradigm Anthems, the home theater setup for the main speakers are ALL class A (high current bipolar devices)
http://statement.anthemav.com/HTML/Products/A_Series/A_Series.html
Second off, the ultra classD in their subwoofer needs a 14lb transformer and has a switching frequency 10 times faster than typical class-D specifications (this means it's literally 10x better). But still isn't good enough to use in thier Anthem ($10,000+) series of amplifiers.
Starting to get the drift ladies and gents?
Above
Yeah.. popcorn is good in here
!
06-08-2006, 01:26 PM
#100
1000 Watt CAFz'r
Join Date: Sep 2001
Posts: 1,120
What are u guys going on about home theatre... this is about car audio so forget those numbers. Yes science is science and measurements are measurements...so what... getting back to the REAL WORLD...what distortion can you actually hear in a car moving down the road, I bet you couldn't hear 1% THD, ok maybe in the mids & highs in a reeeeaaaallly quiet car, but bass forgetaboutit.
And nobody I know uses class-d on anything but subs and maybe midbass.
You show your maturity when you infer that no-one cares about SQ anymore and that it's all SPL now...where did you come up with that one???
Truth is, most boomers quickly grow out of that phase of their life and end up as SQ'ers or SQL'ers and leave those "no SQ at all" days behind unless they're SPL competitors (no offense intended here SPL'ers). Once you get over the fact that a car stereo can make a lot of bass, how long can you listen to just that...my guess not very.
Maybe we have a few people on here who never did grow up and still boom around everywhere going "Hey Look @ Me" and think that is what everyone else must be doing.
And nobody I know uses class-d on anything but subs and maybe midbass.
You show your maturity when you infer that no-one cares about SQ anymore and that it's all SPL now...where did you come up with that one???
Truth is, most boomers quickly grow out of that phase of their life and end up as SQ'ers or SQL'ers and leave those "no SQ at all" days behind unless they're SPL competitors (no offense intended here SPL'ers). Once you get over the fact that a car stereo can make a lot of bass, how long can you listen to just that...my guess not very.
Maybe we have a few people on here who never did grow up and still boom around everywhere going "Hey Look @ Me" and think that is what everyone else must be doing.
