confused about amps (1 Viewer)

[Stefan A]

I was at a friends house the other day listening to his new HT setup. His setup is much different than mine - although we both have good equipment. One of the main differences is that he has a 250 watt 2 channel amp hooked up to his pre-outs for the mains. All I have is a Yamaha RX-V596 (100 watts per channel). So, we watched the depth charge scene from U-571. His wasn't necessarily louder - just more powerful. In my setup, I hear plenty of bass. In his, you get the bass plus a stronger explosion sound (this is real hard to descibe in words). It was as if I have been missing part of the sound track all this time. I know there are other variables involved, but I think the extra amp is making the biggest difference.

So, of course now I want to know if I can re-create that sound if I add an amp to my setup. So I go to tweeter to talk to a salesman about my options. First he tells me that the 596 that I have just won't send "a good signal" to an external amp - so it may not sound too good.

So I am thinking, why the hell do I have preouts on my receiver if it is not worth using?

Then he goes on to tell me that a 2 channel amp for my mains will be a bad combo for a HT setup. He says it will be great for music, but for HT it will make everything uneven. That it will drown out my other channels.

So I am thinking that it is more about the quality of sound than volume. I could use the test tones to adjust the volume of all my speakers compared to each other.

In the end, he was trying to steer me toward a Yamaha rx-v2200 instead of a power amp. I realize that the 2200 is going to be a better receiver than what I have, but they are both 100 watts per channel.

Do you think this salesman was steering me the right way? Will a 2 channel amp combined with my 596 be a bad choice? Is the 2200 going to make my setup sound completely different? As different as an amp would?

Thanks

 

[Selden Ball]

Well, your salesman was certainly confused. So long as you calibrate the sound levels from all of your speakers, the fronts won't drown out the surrounds. Although upgrading the receiver can't hurt, an external amplifier can certainly help, too.

That does bring up a point: have you calibrated your speakers using a sound level meter? This can make a significant difference in the quality of the sound you hear.

Also, an explosion includes many higher frequencies that come from all of your speakers. The quality of your front speakers, especially the center speaker should be considered.

Make sure you've set all of your speakers to be "small" so that all of the low frequencies get redirected to your subwoofer. Although it's tempting to set your fronts as large, they are very unlikely to be able to produce the low frequencies as well as your subwoofer can.

You also have to be careful when you read receiver specs. 100 Watts/channel does not necessarily mean 100 Watts in every channel at the same time. Less expensive receivers can't do that. Their power supplies are not designed to be able to provide that much current.

High quality receivers are rated to provide 100 Watts per channel, all channels driven, 20Hz-20KHz, into 8 Ohms. If they leave out "all channels driven", they mean it can only be provided to one or two channels at a time. If they say "measured at 1 KHz" they mean it can't provide that much power to low frequencies. If they say "into 6 Ohms", then the power available for 8 Ohm speakers is less. Many receivers can provide as much as 33% more power if they're driving a 6 Ohm load intead of 8 Ohms.

Using an outboard 100Watt (or greater) stereo amplifier to drive your front speakers will relieve your receiver of having to drive the most demanding audio channels. It'll be able to use all of its power to drive the center and surrounds with less distortion.

I hope this helps a little.

 

[Richard Travale]

Would adding an external 2 channel amp, with proper level calibration, affect the match between the mains and the center? Not volume wise but as far as clarity and timbre and tonal matching goes. I have read that people find with an amp, they are getting an entirely different sound from their speakers. So what I'm asking is, if I were spending the money anyway, wouldn't it be better to get a 3 channel amp for the LCR than a 2 channel for just the L&R?

 

[Stefan A]

That's a good question about 2 vs. 3 channel amps. I would like to know what others think.

In answer to Seldon's questions - yes, I have matched my speakers with a SPL meter. After reading your response, I listened to the depth charge scenes and played around with various speaker size selections. I could not hear one bit of difference.

 

[Wayne A. Pflughaupt]

Stefan,

I responded to this [identical] post over at the HTT forum, but I’ll go ahead and drop it here, too:

The first problem is that you’re comparing apples to oranges right out of the hole. Your initial comment should be the clue:

His setup is much different than mine - although we both have good equipment.

The operative word here is “different.” Different speakers. Different subs. And most important, different rooms. So you shouldn’t be surprised that his system sounds different.

For instance, if your friend’s room is smaller that automatically gives him a headroom advantage – not to mention the speakers will be closer to the seating position, which would further enhance any feeling of “power” or “impact.”

In addition, his speakers simply may be better at translating dynamics than yours. Furthermore, if his speakers are more efficient than yours, that would certainly give him a “power” advantage – literally.

I think you should do a little acoustical investigating before plunk down the green for an amplifier, Stefan. For instance, if your friend’s room is larger than yours, or his speakers less efficient – where does that leave you??

If this is the case, no amplifier is going to bring you ”up to par” with your friend!

Whatever the case – stay away from that salesman. He needs to find another line of work.

Regards,

Wayne A. Pflughaupt

 

[Kevin. W]

If your friend is willing, borrow his amp and hook it upto your system and see what results you get. This will give you an idea what an amp will do for you. As far as 2 or 3 channel amps if your going to be doing more HT then get the 3 channel. That way your front soundstage is the same all across.

Kevin

 

[chung]

As far as 2 or 3 channel amps if your going to be doing more HT then get the 3 channel. That way your front soundstage is the same all across.

You are not going to improve the matching of the front speakers by driving them from a 3-channel amplifier. You need to match the sound of the 3 speakers, not the amps. Good amplifiers all sound the same. Different models of speakers sound different, and changing amps do not make them sound the same.

As for as the first post in the thread is concerned, the biggest difference between his and his friend's sytem is the speakers, and then the listening environment which affects the way those speakers sound.

 

[Stefan A]

Chung is right about a big difference being the speakers. I don't even remember the brand - so I can't give too much info. They are not modern speakers - they are about 15 years old he said. Subs built into them. The bass was unbelievable - I was skeptical about him not using a sub, but he definitely doesn't need it. I use Mirage OM-10's. I use the OM series all around except for my Rava sub. So, my setup isn't too shabby. But his speakers seem designed for more muscle.

Still, I would love to hear what an amp can do for my setup - weather it be a 2,3, or 5 channel amp.

 

[Yohan Pamudji]

You need to match the sound of the 3 speakers, not the amps. Good amplifiers all sound the same. Different models of speakers sound different, and changing amps do not make them sound the same.

Sure, you need to match the sound of the 3 speakers. That's a given. No amp will make 3 speakers with different timbre sound the same. However, once the 3 front speakers are matched the amp also plays a role. "Good amplifiers all sound the same" is an incredibly broad and, IMO, inaccurate statement. Try having a 2 channel Parasound amp pushing the L/R speakers and an ATI amp running the center channel. There will be a difference.

Currently I have a Parasound HCA-1500A coming in the mail to drive my front 2 speakers. I'll eventually get something like the Parasound HCA-1205A to run the rest including the center speaker since the sound of these amps are very close.

 

[Kevin. W]

Good amplifiers all sound the same

This is not true. All amps are give a different sound. No two amps are designed exactly the same.

Kevin

 

[Aslam Imran]

Was the comparison between your friend's setup and your's a level matched, double-blind test? if not there is no definite way of telling if the differences in sound quality were infact attributable to the use of separate amps.

 

[John Doran]

this sounds a little too familiar.
a "jaleel" by any other name....

 

[Kevin. W]

Was the comparison between your friend's setup and your's a level matched, double-blind test

Before we get into this debate again which in the end leads :rolleyesNO WHERE, like I said in my original post. Borrow the amp from your buddy and see what it does for you. Wether or not his setup is the same as yours, using the amp with your HT setup will give you an idea what it will sound like with external amplification.
Kevin

 

[James Zos]

Yes, this sounds VERY familiar. Aslam Imran--are you really JaleelK? If you are, that's pretty sneaky.

 

[chung]

Yohan said:

This is not true. All amps are give a different sound. No two amps are designed exactly the same.

And not all amps are good. I think the problem here is the definition of "good amps". For me, accuracy is most important. The ideal power amp is a voltage source that reproduces the incoming signal faithfully, with power gain. To me the "goodness" of an amp is how close it comes to that idealization. Now if two amplifiers sound different, then by definition, at least one of the 2 amps is not being accurate. There is only one correct answer! And yes, it is possible to come up with the same answer via different implementations (designs).

Now, for other people, good amps may take on different meanings. Some may like certain colorations (like the tube sound) and they want their amp to sound that way. To them, that is a good amp. Obviously I do not share that definition. But, hey, it's a free country!

You can have two expensive amps sound different driving the same speakers. In most cases, that is because the speakers in question present a difficult load over frequency for the amp(s), and the amp(s) cannot remain an ideal voltage source with that kind of load, over frequency. That also means that the amp(s) is no longer accurate. The better the two amps are, the more insignificant their differences will be.

 

[Stefan A]

My friend agreed to bring his amp over to my place. So, in a few weeks, I will know if that was the difference.

 

[Larry B]

Chung:
All amps are imperfect, inlcuding the best ones money can be. As such, they all color the sound to some degree; the nature of the coloration depends on the manufacturers' preferences and abilities. For example, Levinson and Krell both make top-notch amplifiers, but the difference in sound between their products is quite apparent (at least for music; I don't know about for HT). Of course, I think most everyone will agree that the sonic differences between amps is less than those between different brands of speakers.
Larry

 

[Aslam Imran]

Yes, this sounds VERY familiar. Aslam Imran--are you really JaleelK? If you are, that's pretty sneaky.

I am new to this forum so I dont know what you guys are talking about and who JaleelK is.

 

[John Doran]

chung,

Now if two amplifiers sound different, then by definition, at least one of the 2 amps is not being accurate. There is only one correct answer!

this is not, strictly speaking, true : it is entirely possible, for instance, for neither amp to be accurate.
it is not even clear that it would be possible to to say that one of the amps must be more accurate, since it's also not clear that inaccuracies in amplification are necessarily comparable; some may be, perhaps, but not all.
for example, if one amp is "warm" but images well, and the other images poorly, but is more transparent, which amp is more accurate?
anyway. i'm agreeing with Larry - all amps are inaccurate to some degree, since no component in an audio system can improve the signal, but only make it worse.
the trick is to find an amplifier that has the most tolerable inacuracies. whether or not that means "inaudible" is a personal question, since not everyone hears the same...
- jd