How much power?
10-14-2003, 09:23 AM
#11
Originally posted by PEI330Ci:
....Now for the true audio purists out there, anybody else have an amp running pure Class "A"?
....Now for the true audio purists out there, anybody else have an amp running pure Class "A"?
10-14-2003, 10:40 AM
#13
1000 Watt CAFz'r
Thread Starter
Join Date: Oct 2003
Posts: 1,783
Chadxton, thanks for the compliment. I enjoy spending the time to write well. Dude, you are going to scare yourself with that much power!!!
As for the amp you ask about, it may be hard to tell.
Most amplifiers are split into 3 separate sections along the signal path. The first 2 are types of "pre-amplifiers" for the actual output devices that drive your speakers. While it does take some effort to run the first 2 stages in "Class A" mode, it's the final output stage that's really hard to do. The bottom line is heat, and the output stage generates lots of it. Some high quality amplifiers run the first 2 stages in Class A and the outputs in Class A/B. While this improves the smoothness of the signal, it still gets the switching noise of the output stage added. There are amplifiers that claim to be Class A that fall into the above catagory. I don't know if yours is one of them.
To be honest here, running Pure Class A(all 3 stages) generates a ton of heat. Many people would be hard pressed to hear the difference. The diffence is subtle, and most audible when the car is parked and the engine off. I find the sound is best characterised as smoother. If there are harsh passages in music, it makes them just a bit more bearable. Vocals however recieve the most benifit, but again, it's best heard when you are parked.
Lemonlime, you seem to have a very well balanced system. How do you like the Four.1i? I mostly use mine as a volume control.
Adam
As for the amp you ask about, it may be hard to tell.
Most amplifiers are split into 3 separate sections along the signal path. The first 2 are types of "pre-amplifiers" for the actual output devices that drive your speakers. While it does take some effort to run the first 2 stages in "Class A" mode, it's the final output stage that's really hard to do. The bottom line is heat, and the output stage generates lots of it. Some high quality amplifiers run the first 2 stages in Class A and the outputs in Class A/B. While this improves the smoothness of the signal, it still gets the switching noise of the output stage added. There are amplifiers that claim to be Class A that fall into the above catagory. I don't know if yours is one of them.
To be honest here, running Pure Class A(all 3 stages) generates a ton of heat. Many people would be hard pressed to hear the difference. The diffence is subtle, and most audible when the car is parked and the engine off. I find the sound is best characterised as smoother. If there are harsh passages in music, it makes them just a bit more bearable. Vocals however recieve the most benifit, but again, it's best heard when you are parked.
Lemonlime, you seem to have a very well balanced system. How do you like the Four.1i? I mostly use mine as a volume control.
Adam
10-14-2003, 11:09 AM
#14
500 Watt CAFz'r
Join Date: Jul 2003
Posts: 756
So far, I've been quite happy with it.
My Xtant amplifer can accept pretty high signal voltage, so the line driving capabilites were my primary reason for getting it. It's also nice to have some control of a few frequency bands in the driver's seat. Blends into my dash beautifully too with the amber back lighting.
My Xtant amplifer can accept pretty high signal voltage, so the line driving capabilites were my primary reason for getting it. It's also nice to have some control of a few frequency bands in the driver's seat. Blends into my dash beautifully too with the amber back lighting.
10-14-2003, 11:20 AM
#15
I know straight class B basically works only when there is a signal of about ±.6 volts in order for it to register. That creates distortion every time the sine reaches the 0 center point (whatever you may call it). AB amps run at A for about 5% of the volume to compensate for that loss in signal. That's the way I understand the difference between AB and B class amps.
I picture class A amps as basically running at full output 100% of the time, using the volume control as a "clutch". That's how I figure they run so hot.
The Denon I have is a 4 channel with a twin power supply. Does that make any difference whether or not it is Class A or not? It is a bridgeable amp as well.
[ October 14, 2003, 12:24 PM: Message edited by: Chadxton ]
I picture class A amps as basically running at full output 100% of the time, using the volume control as a "clutch". That's how I figure they run so hot.
The Denon I have is a 4 channel with a twin power supply. Does that make any difference whether or not it is Class A or not? It is a bridgeable amp as well.
[ October 14, 2003, 12:24 PM: Message edited by: Chadxton ]
10-14-2003, 12:38 PM
#16
Guest
Posts: n/a
Class A basically means that your idle current is equal to your max current as your output devices are always on, Class AB means there are two sets of output devices one for the positive part of the waveform and one for the negative. You get crossover distortion as one set switches off and the other switches on.
Dual power supplies can be used in any kind of amp, same witrh bridging abilities.
Dual power supplies can be used in any kind of amp, same witrh bridging abilities.
10-14-2003, 12:49 PM
#17
Guest
Posts: n/a
Originally posted by Team Obsession:
</font><blockquote>quote:</font><hr />Originally posted by Dukk:
I used to run a Punch40 to my 3way front end - so about 40rms per side. It was alright but never had the impact I wanted. Now I run 2channels of a Punch 4080 (approx 90x2) and it's almost enuf.
Personally, 100watts RMS per side up front is my lower limit. Not so much for the volume it can reach but for the dynamics you retain at moderate levels.
</font><blockquote>quote:</font><hr />Originally posted by Dukk:
I used to run a Punch40 to my 3way front end - so about 40rms per side. It was alright but never had the impact I wanted. Now I run 2channels of a Punch 4080 (approx 90x2) and it's almost enuf.
Personally, 100watts RMS per side up front is my lower limit. Not so much for the volume it can reach but for the dynamics you retain at moderate levels.
or do you have a formula you use like that? and what do you think of Focal components(not a huge fan of the Mb quart tweeter either, just incase they sound like that) [img]graemlins/dunno.gif[/img] Thanx [img]graemlins/thumb.gif[/img] </font>[/QUOTE]Over time I have found that subwoofer power is an interesting thing. IMO once there is ~250-350 watts of sub power you can run your front end power anywhere from 50x2 to 500x2 and it sounds good at either end of the scale. When you figure that on a specific woofer system, the difference from 300 watts to 600 watts is only theoretically 3db you can see how once there is 'enough bass' to provide impact and bottom end that you can really pour on the top end power without skewing the balance too much.
So with lower power systems, often the woofer power is 2x or 3x the front end power but in moderate and high power systems the power can be equal or even higher for the front stage.
Of course this is just my opinion.
10-14-2003, 05:47 PM
#20
I like the way the Holdaways think...
My Macintoshes are puting about 110 wrms into each of my speakers on my 3-way front end. so about 650 rms on the front end at 4 ohms.
once its done i'll post how it came out...
My Macintoshes are puting about 110 wrms into each of my speakers on my 3-way front end. so about 650 rms on the front end at 4 ohms.
once its done i'll post how it came out...
