Amplifiers
02-18-2003, 07:06 AM
#1
2000 Watt CAFz'r
Thread Starter
Join Date: Jan 2001
Posts: 2,026
I get mixed messages around this place about what is good and what is not. In particular I am wondering about profile amps. I know that they are bottom end amps, but I was looking at one (CA 800) which pushed 200x2 RMS @ 4 ohms, and 600x1 RMS @ 4 ohms. These stats were tested at 14.4 v, and are the RMS ratings not the peak (peak is 400x2 @ 4 ohms). All of that for $179 US (or cheaper, depending where you look). I think that is a lot of wattage for the buck.
Now some of you might say "distortion, distortion, distortion" but the stats on the amp are THD <0.07% and S/N 102 db which is comparable to most other amps on the market for way more cash. So, then, why do these amps "suck" if they apparently do the same work for half the buck?
Now some of you might say "distortion, distortion, distortion" but the stats on the amp are THD <0.07% and S/N 102 db which is comparable to most other amps on the market for way more cash. So, then, why do these amps "suck" if they apparently do the same work for half the buck?
02-18-2003, 07:15 AM
#2
1000 Watt CAFz'r
Join Date: Mar 2001
Posts: 1,626
With a 60 amp fuse rating, assuming it is capable of drawing 60 amps at full power, in order to do 600 watts bridged, the amp would have to be 70% efficient. Most class-AB amps have a 50% efficiency at the rated RMS power and I would expect it to be able to around 400 watts or so. IF it is capable of drawing 60 amps.
The 'cheaper' amp producers may test their amps at a higher voltage and/or distortion level, or for very short periods of time, also with ONE frequency rather than an average over 20-20000Hz. I'm sure it is fully capable of making 600 watts rms, for maybe a second with 18V input and 10% distortion.
Of course this is all based on what I hear and may not be true...who knows. That's my input anyways
and those s/n and thd rations are probably taken at 1/3 power rather than the rated RMS
[ February 18, 2003, 08:19 AM: Message edited by: hiredgoon ]
The 'cheaper' amp producers may test their amps at a higher voltage and/or distortion level, or for very short periods of time, also with ONE frequency rather than an average over 20-20000Hz. I'm sure it is fully capable of making 600 watts rms, for maybe a second with 18V input and 10% distortion.
Of course this is all based on what I hear and may not be true...who knows. That's my input anyways
and those s/n and thd rations are probably taken at 1/3 power rather than the rated RMS
[ February 18, 2003, 08:19 AM: Message edited by: hiredgoon ]
02-18-2003, 08:35 AM
#3
Guest
Posts: n/a
you can't really go by the fuse on the amp ........my 700 watt class a/b soundstream's only have 60 amp fuses
if the specs say the amps makes 600 watts rms , I'm sure it does ......
cheaper amps usually test wattage at 14.4 volts, but that's not always true
I remeber a test quite a while back of a profile california amp and it did well met all specs.......can't remember the mag though [img]smile.gif[/img]
if the specs say the amps makes 600 watts rms , I'm sure it does ......
cheaper amps usually test wattage at 14.4 volts, but that's not always true
I remeber a test quite a while back of a profile california amp and it did well met all specs.......can't remember the mag though [img]smile.gif[/img]
02-18-2003, 08:46 AM
#4
Guest
Posts: n/a
what you may find on cheaper amps is lacluster signal processing sections (shallow crossover slopes, fixed non adjustable crossover points, sometimes no signal processing)
also while almost all amplifiers sound pretty much the same, the signal processing section of the amp can affect sound quality a lot
most cheaper amps can't handle low impedance loads (ie:2 ohms mono), but who cares if 4 ohms mono is all you need
most only make exactly what they're rated for (some a little less), people seem to like the idea of buying a 400 watt amp that really makes 600 watts
why I don't know ........
I have found some cheaper amps to run very hot and thermal out a lot when pushed hard.....
but that said they do offer pretty good bang for the buck
oh yeah and I think a lot of people by more expensive stuff for the prestige too [img]smile.gif[/img]
I think sony xplode amps offer pretty good bang for the buck if used properly
they make a 150 x 2 watt amp that sells for about 275 that would make a great front stage amp, and a class d mono that does 600 watts rms into 2 ohms that sells for about 300 bucks
problem with those 2 amps is sony says the 2 channel is 2 ohm stable and the mono is 1 ohm stable, they melt at those impedances and thus have a bad name, but if used at 4 ohm stereo and 2 ohm mono they are awsome bang for the buck IMO .......
also while almost all amplifiers sound pretty much the same, the signal processing section of the amp can affect sound quality a lot
most cheaper amps can't handle low impedance loads (ie:2 ohms mono), but who cares if 4 ohms mono is all you need
most only make exactly what they're rated for (some a little less), people seem to like the idea of buying a 400 watt amp that really makes 600 watts
why I don't know ........I have found some cheaper amps to run very hot and thermal out a lot when pushed hard.....
but that said they do offer pretty good bang for the buck
oh yeah and I think a lot of people by more expensive stuff for the prestige too [img]smile.gif[/img]
I think sony xplode amps offer pretty good bang for the buck if used properly
they make a 150 x 2 watt amp that sells for about 275 that would make a great front stage amp, and a class d mono that does 600 watts rms into 2 ohms that sells for about 300 bucks
problem with those 2 amps is sony says the 2 channel is 2 ohm stable and the mono is 1 ohm stable, they melt at those impedances and thus have a bad name, but if used at 4 ohm stereo and 2 ohm mono they are awsome bang for the buck IMO .......
02-18-2003, 10:39 AM
#5
500 Watt CAFz'r
Join Date: Aug 2001
Posts: 866
Unfortunatly, it is sometimes very difficult to rate an amplifier based on power specs provided by
manufactures(most!) Now not to say there are not any companies who do give usefull information.
There are so many factors involved,
power is one thing , but what about the ability of the amp to control the speaker at that given power? Unfortunatly THD means nothing and is a term thrown around car audio too much.
Bang for the buck is a great way to shop for an amp. In most cases reputable companies have a good track record and that is why I would stick to them
[ February 18, 2003, 11:42 AM: Message edited by: slow/n\low ]
manufactures(most!) Now not to say there are not any companies who do give usefull information.
There are so many factors involved,
power is one thing , but what about the ability of the amp to control the speaker at that given power? Unfortunatly THD means nothing and is a term thrown around car audio too much.
Bang for the buck is a great way to shop for an amp. In most cases reputable companies have a good track record and that is why I would stick to them
[ February 18, 2003, 11:42 AM: Message edited by: slow/n\low ]
02-18-2003, 11:52 AM
#6
2000 Watt CAFz'r
Thread Starter
Join Date: Jan 2001
Posts: 2,026
Thanks Dodge; most of what you said is what I suspected. Myself, I don't push my equipment hard, my wife doesn't appreciate loud at all. Also I will only be running a single pioneer 4 ohm sub. So I shouldn't woory too much about reliability issues of heating up etc.
As for the crossover slope, if I were to pick up an auxillary x-over for $50 I should be fine . . .
As for the crossover slope, if I were to pick up an auxillary x-over for $50 I should be fine . . .
02-18-2003, 01:42 PM
#8
Guest
Posts: n/a
Dodge is bang on everything he said. [img]graemlins/thumb.gif[/img]
Twice now I have been very close to dropping those red Sony things in my car because I know from experience that they have good power, are cheap, and are quite reliable if you don't do anything stupid.
Twice now I have been very close to dropping those red Sony things in my car because I know from experience that they have good power, are cheap, and are quite reliable if you don't do anything stupid.
02-18-2003, 01:50 PM
#9
Guest
Posts: n/a
actualy I'd love to do a kickass system using the sony amps (as ugly as they are) just to see the faces on a couple guys I know that say they're absolute total crap [img]smile.gif[/img]
actually a friend has an m620......(black face model) still going strong in his chevy, it's never skipped a beat in the last 3 years ......can't say that for my 1000 dollar alpine
or my 1200 dollar kenwood for that matter (sometimes I'm tempted to buy a 150 dollar cd player......they never seem to quit)
actually a friend has an m620......(black face model) still going strong in his chevy, it's never skipped a beat in the last 3 years ......can't say that for my 1000 dollar alpine
or my 1200 dollar kenwood for that matter (sometimes I'm tempted to buy a 150 dollar cd player......they never seem to quit)
02-18-2003, 02:00 PM
#10
Originally posted by maltesechicken:
All of that for $179 US (or cheaper, depending where you look). I think that is a lot of wattage for the buck.
All of that for $179 US (or cheaper, depending where you look). I think that is a lot of wattage for the buck.
