Power quality for speakers

[Joe Schmoe]

Don't be so hasty

If you don't exceed the Yam's design limits, why would there be audible differences? They are both well designed amps. Sure, the Parasound may have some capability that the Yam doesn't, but that doesn't prevent them sounding the same if you don't exceed the design limits of the least component.

That makes perfect sense. Audible differences should be a result of exceeding the Yam's limits. When operating well within the limits of both amps, neither should be better.

 

[TinleyJake]

You may be interested in reading this paper:

David Rich and Peter Aczel, 'Topological Analysis of Consumer Audio Electronics: Another Approach to Show that Modern Audio Electronics are Acoustically Transparent,' 99 AES Convention, 1995, Print #4053.

He has been examining, testing and listening to audio for a while now.

Here is one old Yam integrated and a very expensive and I guess well regarded amp comparison. 3 people, 'golden ears' couldn't differentiate between them.

Still another one. He has been at this for a few days as well:

http://www.mastersonaudio.com/audio/20020901.htm

One more:

http://www.soundandvisionmag.com/assets/download/AmpSpekerInterface.pdf

or two:

http://webpages.charter.net/fryguy/Amp_Sound.pdf

The key in all this is within design limits.

For my benefit I'm glad I opened up this can of worms. Being semi-ignorant in the audio field, I've learned more from this thread then I ever expected.

I think I'm finally starting to understand. If I was starting out from scratch, the correct progression is to start out with auditioning speakers and finding out what appeals to my ear. From there I would want to evaluate the nature of what the speaker demands power wise to perform to my expectations.

According to the Sound and Vision article you posted, some speakers may not audibly benefit from a seperate amplifier yet some some speakers may sound decent with an integrated preamp/amplifier but to make it really "sing" may require a dedicated certain style amplifier, tube for instance.

Don't get me wrong, one of the guys I dealt with was just downright snobbish and only wanted to talk about the $30K installs he's currently involved with. As a sales guy he seemed incapable of adapting to different customers needs.

So what the question should have been is I've decided on speaker xxxxx, would this speaker benefit from a certain style engineered dedicated amplifier or is it less demanding and would most likely perform well with most quality integrated receivers?

Jake

 

[Joe Schmoe]

So what the question should have been is I've decided on speaker xxxxx, would this speaker benefit from a certain style engineered dedicated amplifier or is it less demanding and would most likely perform well with most quality integrated receivers?

Something else to consider: The designers of budget speakers tend to assume that they will be driven by budget receivers, and therefore make a point of making them easy to drive. High end speakers are much more likely to be inefficient, have low impedence dips, etc.

 

[wire]

Something else to consider: The designers of budget speakers tend to assume that they will be driven by budget receivers, and therefore make a point of making them easy to drive. High end speakers are much more likely to be inefficient, have low impedence dips, etc.

Good point .

 

[Seth=L]

Something else to consider: The designers of budget speakers tend to assume that they will be driven by budget receivers, and therefore make a point of making them easy to drive. High end speakers are much more likely to be inefficient, have low impedence dips, etc.

There is a lot of truth in this. Many high-end speakers require the services of a high-power amplifier that is capable of handling virtually any load you can throw at it. That would be the sentiments of Krell, McIntosh, and Bryston.

 

[no. 5]

As I mentioned to Peng, don't forget about the inefficiency of our hearing at the two ends of the audio band. That is to hear level changes which is indicative of a frequency response fall off or boost, you need a lot to detect it with test tones and a bunch more with music.

Yeah, it might not be necessary to have a amplifier that has a flat response to within 0.07dB 20Hz to 20kHz, but it certainly would be cool.

I posted some charts but 16kHz is minimum of 1 dB with norm of 3 dB. Can you hear 20kHz? I cannot. To low end is similar, or worse.
One reason a sub is measured to 10 % THD. Axiom has conducted some distortion testing. At low frequency, they found even 100% might not be easy to detect. That's not me, it is research.

I used to be able to hear 20kHz .
About Axiom's testing; around what frequencies did they find 100% THD hard to detect? Maybe if you have a link to the whole study? Thanks.

 

[no. 5]

Having a amplifier with more power than a receiver would be good if you happen to sit fairly far away from your speakers; the amount of power needed to get to any SPL will be a bit higher if you are sitting 12 feet away from your speakers then if you are sitting only 7 feet.

But I would guess that the number of people around here that need more power because of the size of there room is small.

 

[Jey Jockey]

These days I think there is a huge misconception as to what type of amplifiers are in most receivers vs. separates. I see the term on here all the time "properly designed amplifier" without anyone stopping to explain what that term means both in general and to them individually. All power & amplifiers are not the same when comparing between different receivers let alone receivers to separates, regardless of wattage claims.

There is a country mile of difference in engineering, build quality, and execution when comparing the amplifier in a 125 watt per channel receiver to something like a 125 watt Parasound Amp.

Could anyone give me a breakdown with real life practical experience as to which models of receivers have a "proper" amplifier inside and which models have "improper" amplifiers inside and then contrast them to separates?

Another question to take it a step further... With rapidly changing manufacturing practices, turnover in engineering & design teams, and the increasing pressure from consumers to lower costs can anyone tell me that these "proper" or "improper" amplifiers don't change considerably from year to year (or even quarter to quarter)? It cracks me up when people think that just because yester years "Insert receiver here" model performed well and was "properly" designed that this years will be too. Or those 125 watts from an $800 Yamaha receiver (with a zillion other features/functions) is equal to 125 watts from a Parasound dedicated amp that costs $1800. It's not true.

Back to the original post...
Bottom line when looking into a speaker upgrade: If you properly bought your equipment the last time you went shopping, your receiver/amplifier will be well mated to fit your speakers. If you do a major upgrade to high-fi speakers you need to make sure the electronics match as well. Is that the first thing you buy? Well, probably not. However, I will tell you that your stereo shop makes way way more money on selling you speakers than they do electronics. The difference is not even close. So, if they are recommending you upgrade electronics, I would sit down and listen as to why. If the salesman is full of crap and can't articulate his reasoning for doing so... leave the store immediately.

I'm not trying to flame the thread at all, but I see these terms always knocked about in generalities and without many long term, real life experiences offered. I’m just trying to understand where people are coming from with their convictions vs. those of which they’ve read from others.

Finally someone who put my thoughts into words for me! I couldn't agree more and thank you for your insight.
Lets also remember that some people hear alot differently than others, some are more able to hear subtle changes some are not.

Chris

 

[PENG]

Peng
Now , i took my Bryston in for sevicing a few years ago ( great customerservce ) , I hooked up my a Sony N220 4 channel ( i bridged it for more power 100 x 2 ) for a temporary replacement for my Polk 2b's . I couldnt even listin to my system , you ppl. say speakers are the most important ( yes they are if you match them properly ) . The 2b's with sony at low levels had no nothing (bass or Mid or depth) and was hard to listin to , i wasnt going to even try to push the volume up ( scared that my tweets would say goodbye ) . Now with my 4b , everything is back , great depth ,bass and mids and the highs are so sweet .
The N220 is now strickly a AV amp (which i originally bought for ) in my AV system , which it does just fine for movies and matched with some Klipsch loudspeakers . I also picked up a back up amp for the polks , a Carver TFM-35 which i use as my center channel amp ( made my center come alive ) .
Some loudspeakers need power to make the sound Full , by the way my Polks 2b's are 89db at 1 meter and are 6ohm speakers .

Wire, just to be clear, I was referring to well designed amps that have very similar specifications that have been, or can be verified by lab measurements (see my other post). I don't know anything about your Sony but not all Sony products post specifications that follow the same standards/rules as other main stay reputable manufacturers. I do feel that my 4BSST sounds a little better than my Adcom, Denon and Sony ES receiver (one that weighs 21 kg), but no day and night differences heard by me or anyone who had visited my house. I don't have high end speakers, but I know my Veritas have more than enough resolution relative to speakers owned by some of the people who reported day and night differences simply by adding an entry level amp to their mid level receivers.

What you said about having to match amps with speakers I don't buy, well, may be I can buy it to a point... This is more science than art; it is not like matching colors and shapes. Reputable amp manufacturers would not intentionally design their amp to match a particular make of speakers. Conversely, loudspeakers manufactures are not going to design their products to match a particular make of amplifiers. There are established standards that they can based their designs on, instead of investing their time and money on something unpredictable, and bank their success on trial and error, hit and miss approach. That being said, I do agree that some speakers, usually (but not always) the more expensive ones could be more difficult to drive. Your Polk is a good example, but it is mainly to do with the power output/ability to deliver high current into low impedance and/or highly inductive loads.

 

[PENG]

Having a amplifier with more power than a receiver would be good if you happen to sit fairly far away from your speakers; the amount of power needed to get to any SPL will be a bit higher if you are sitting 12 feet away from your speakers then if you are sitting only 7 feet.

But I would guess that the number of people around here that need more power because of the size of there room is small.

no.5, you may be surprised! The inverse square rule applies only to open field. In a room, it depends on the acoustic environment. In other words, it is even possible that you get higher SPL sitting at 12 ft than 7 ft from your speakers.

 

[mtrycrafts]

Yeah, it might not be necessary to have a amplifier that has a flat response to within 0.07dB 20Hz to 20kHz, but it certainly would be cool.
[/QUPTE]

Yes, of course But, 0.00 dB variation would blow me away

I used to be able to hear 20kHz .
About Axiom's testing; around what frequencies did they find 100% THD hard to detect? Maybe if you have a link to the whole study? Thanks.

It is in the low band someplace:

http://www.axiomaudio.com/distortion.html#

 

[mtrycrafts]

Having a amplifier with more power than a receiver would be good if you happen to sit fairly far away from your speakers; the amount of power needed to get to any SPL will be a bit higher if you are sitting 12 feet away from your speakers then if you are sitting only 7 feet.

But I would guess that the number of people around here that need more power because of the size of there room is small.

One must also consider the speakers ability to output high spl, or what the limit is without audible distortion. This is not published, usually.

Here is a link to some speaker measurements, including their distortion level at 90 dB spl and 95 dB spl. Read the notes linked how they did the distortion levels. The dB difference between the two curves, converted to % of dist.

http://www.soundstageav.com/speakermeasurements.html

This link will show dB spl as distance changes, in a room, not open space as it is different. Unfortunately I cannot give you a direct page link but follow: sound and hearing, inverse square law, measurements and have at it

http://hyperphysics.phy-astr.gsu.edu/hbase/hframe.html

 

[wire]

Wire, just to be clear, I was referring to well designed amps that have very similar specifications that have been, or can be verified by lab measurements (see my other post). I don't know anything about your Sony but not all Sony products post specifications that follow the same standards/rules as other main stay reputable manufacturers. I do feel that my 4BSST sounds a little better than my Adcom, Denon and Sony ES receiver (one that weighs 21 kg), but no day and night differences heard by me or anyone who had visited my house. I don't have high end speakers, but I know my Veritas have more than enough resolution relative to speakers owned by some of the people who reported day and night differences simply by adding an entry level amp to their mid level receivers.

What you said about having to match amps with speakers I don't buy, well, may be I can buy it to a point... This is more science than art; it is not like matching colors and shapes. Reputable amp manufacturers would not intentionally design their amp to match a particular make of speakers. Conversely, loudspeakers manufactures are not going to design their products to match a particular make of amplifiers. There are established standards that they can based their designs on, instead of investing their time and money on something unpredictable, and bank their success on trial and error, hit and miss approach. That being said, I do agree that some speakers, usually (but not always) the more expensive ones could be more difficult to drive. Your Polk is a good example, but it is mainly to do with the power output/ability to deliver high current into low impedance and/or highly inductive loads.

The N220 by Sony (they say its has the same inside as the ES model of that year ) is not a bad amp , its better than yammy . But it cant Amplify my Polk 2b's properly , the Bryston and Carver ( which sound different in there own right ) do a fine job and up to my standard . The speakers sound much different with these Amps ( that mightbe a tad bit hard to drive , 89db @ 6 ohms ) .
Now if thats my case , try and answer Jeys question properly .
I also agree with Intheindustry said in his post . I also know the markup on speakers ( thats where they make there money ), I got my 2b's way back when @ cost and there as good as new today .

 

[wire]

What you said about having to match amps with speakers I don't

I remmber when i bought the 2b's , the most sold amp for the SDA series was Carver . I went against the grain and went with Bryston ( alittle brighter and tighter bass ) vs the Carver series , although i needed a pre to calm the Bryston down abit and went with the Carver CT-7 .
If you go to the polk forum or the Carver forum , the same thing sticks out that the Carver amps where a great match with the SDA series . The SdA's can handle hords of good power and need alot of power to sound up to there standard and make there sound stage open up .
Note
I want to try my SP3 hooked up to the SDA's and see what they sound like . The SP3 is only 38 x 2 but it sounds like alot more than that .
So i have experenced there is a difference matching your speakers to a Amp/Preamp .

 

[Seth=L]

The N220 by Sony (they say its has the same inside as the ES model of that year ) is not a bad amp , its better than yammy . But it cant Amplify my Polk 2b's properly , the Bryston and Carver ( which sound different in there own right ) do a fine job and up to my standard . The speakers sound much different with these Amps ( that mightbe a tad bit hard to drive , 89db @ 6 ohms ) .
Now if thats my case , try and answer Jeys question properly .
I also agree with Intheindustry said in his post . I also know the markup on speakers ( thats where they make there money ), I got my 2b's way back when @ cost and there as good as new today .

Just because it is similar to the ES amp doesn't mean it is stable with low loads. Get some specifications then we can talk.

 

[wire]

Just because it is similar to the ES amp doesn't mean it is stable with low loads. Get some specifications then we can talk.

Specs , this thing is old , i dont have the manual . My point is it cant properly push my 2b's and its 100 x 2 , they tell me all amps at low volume sound the same .
Again this Sony N220 does just fine in my AV set up . Its 60 x 4 .

 

[Seth=L]

Specs , this thing is old , i dont have the manual . My point is it cant properly push my 2b's and its 100 x 2 , they tell me all amps at low volume sound the same .
Again this Sony N220 does just fine in my AV set up . Its 60 x 4 .

Well you can't take every thing that is said and make it fact. Most posts on the forum are not complete answers, that would take up a lot of time and space.

Stating that the amp does 100 watts x 2 means almost nothing. We don't know if that is from 20hz-20khz, both channels driven, and most importantly the impedance that it is rated for.

 

[wire]

Well you can't take every thing that is said and make it fact. Most posts on the forum are not complete answers, that would take up a lot of time and space.

Stating that the amp does 100 watts x 2 means almost nothing. We don't know if that is from 20hz-20khz, both channels driven, and most importantly the impedance that it is rated for.

Its a main streem little amp , probs equal to yours .

 

[Seth=L]

Its a main streem little amp , probs equal to yours .

Probably equal to the Yamaha, but I wouldn't bet that about the Fisher. It has a massive power consumption for it's rated power, I wish I had the specs for the thing. I could be wrong though. I will say this, it sounds no different than the Yamaha with the NHTs, which happen to be 8 ohms nominal, I don't know how low they dip.

 

[no. 5]

The inverse square rule applies only to open field. In a room, it depends on the acoustic environment. In other words, it is even possible that you get higher SPL sitting at 12 ft than 7 ft from your speakers.

oops, I forgot about room interaction.

Thanks for the correction PENG.