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post #31 of 56 Old 10-22-2012, 02:44 PM
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ArnyK and mcnarus have enough experience to confidently tell you that they're all the same.
The opposite is true: We have enough experience to tell you that they aren't all the same. But most of them are close enough that you cannot tell the difference.
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And the ones that claim to be "different" or "better" are only out to take your money.
Everybody is out to take your money.

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post #32 of 56 Old 10-22-2012, 06:02 PM
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sorry just funny and now i give up completely
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opposite is true: We have enough experience to tell you that they aren't all the same.

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post #33 of 56 Old 10-23-2012, 04:41 AM
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Originally Posted by bthrb4u View Post

A speaker with a higher sensitivity obviously need better amplification to make it play louder.

No, a speaker with higher sensitivity will play louder with no change of amplification at all. That's what "higher sensitivity" means. For a given amount of power, the more sensitive speaker plays louder with no other changes.
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A class A/B amp will not make the bass louder unless you turn the volume up but it will give more body and make it much more punchy.

Amplfier biasing class all by itself has no effect whatsoever on the body or punchy qualities of sound, given that the biasing is such that the amplifier plays without low level distortion.

An improperly biased amplifier will have excessive distortion at low power. That distortion is usually described with words like gritty, harsh and "grungey", and becomes less and less audible as the loudness increases.

It is properly to properly bias audio amplifiers that have a variety of classes including A, AB, D, G, and H. There are two amplifier classes B and C that are impossible to bias for low distortion at all operating levels. They are ordinarily used for amplifying narrow bands of frequencies (bandwidth as compared to operating frequency - the actual bandwidth may be many megahertz), such as is done in the RF sections of radio, TV, cellphone, and microwave transmitters. In these applications low level distortion is not a problem.
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post #34 of 56 Old 10-23-2012, 07:44 AM
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yes sometimes i type to fast for my own good and yes i wrong about both lol but what i wrote is not the same as what i think. I know about speaker sensitivity and i really can't believe that i wrote that it will make the bass louder as i did mean more punchy and body. Even though there is not a difference in volume, the difference in punch and body gives the effect of louder bass but like everyone says, if you were to measure it there would be no change.

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post #35 of 56 Old 10-23-2012, 09:08 AM
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Originally Posted by bthrb4u View Post

yes sometimes i type to fast for my own good and yes i wrong about both lol but what i wrote is not the same as what i think. I know about speaker sensitivity and i really can't believe that i wrote that it will make the bass louder as i did mean more punchy and body. Even though there is not a difference in volume, the difference in punch and body gives the effect of louder bass but like everyone says, if you were to measure it there would be no change.
Oh, man, just stop digging.

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post #36 of 56 Old 10-23-2012, 05:24 PM
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i don't know what you're talking about.
No, you don't.
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amps make everything sound sooooo much different.
Only if:

1) You're comparing them playing at different volume levels, in which case you're hearing the effect of different volume levels, not any difference in inherent sound quality. Match their outputs exactly, and those differences inevitably disappear; or

2) You're just imagining things, based on a predisposition to believe they sound different, even when they don't.
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I heard an amp onetime that slowed time down in the mids and highs so bright that they actually melt diamonds
ohhh, and the excessive sibilance.
You have a very vivid imagination. You should write audio reviews.

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post #37 of 56 Old 10-23-2012, 05:29 PM
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only they don't
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post #38 of 56 Old 10-23-2012, 06:08 PM
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Originally Posted by bthrb4u View Post

yes sometimes i type to fast for my own good and yes i wrong about both lol but what i wrote is not the same as what i think. I know about speaker sensitivity and i really can't believe that i wrote that it will make the bass louder as i did mean more punchy and body. Even though there is not a difference in volume, the difference in punch and body gives the effect of louder bass but like everyone says, if you were to measure it there would be no change.

if you "measure" something, and there is no change.... well, then there is no difference...

one would think this would be intuitively obvious...
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post #39 of 56 Old 10-23-2012, 06:36 PM
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I just got done reading a lot more on amps and i feel like an idiot. I think i understand a lot more now. so, basically, when buying an amp, you are worried about efficiency and distortion and the ability to keep the flow coming at all times no matter what, through all frequencies. I did understand that when someone asks how an amp sounds they where basically asking how capable it is. but i, with my inexperience, also thought they were voiced too to have differences in the sound. I actually know why i thought this. A company named Schiit makes headphone amplifiers and they said they "voiced" the amplifier i have with a certain model headphone in mind. It is a ss a/b amp.
Thank you audioholics
http://www.audioholics.com/education/amplifier-technology/10-things-about-audio-amplifiers

I read that speakers like electrostats need more current than voltage.
Can anyone chime in on this and what an amp needs to be a good amp for them.

Also why is it that some people say that some speakers need high voltage to "really open them up"

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post #40 of 56 Old 10-23-2012, 06:52 PM
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I just got done reading a lot more on amps and i feel like an idiot.
But you're not an idiot. You're just a guy who's subject to the same psychoacoustic illusions as everybody else, and you've probably read enough gibberish by other people subject to those illusions. It's perfectly logical to assume that amps make a difference, until you scratch below the surface and discover that they usually don't.
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I did understand that when someone asks how an amp sounds they where basically asking how capable it is. but i, with my inexperience, also thought they were voiced too to have differences in the sound. I actually know why i thought this. A company named Schiit makes headphone amplifiers and they said they "voiced" the amplifier i have with a certain model headphone in mind.
Of course, if you make a product that pretty much sounds like all your competitors' products, you've got to come up with some sort of BS like that to differentiate yourself.
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I read that speakers like electrostats need more current than voltage.
Can anyone chime in on this and what an amp needs to be a good amp for them.
Someone else will have to explain current vs. voltage for you. But speakers have an impedance curve—basically the resistance they present to the amplifier, which varies with frequency. Electrostats can have very low impedances, which can be harder for an amp to drive. (Think of how much more pressure you need to push water through a wide pipe (low resistance) than through a narrow pipe (high resistance).)
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Also why is it that some people say that some speakers need high voltage to "really open them up"
Because they don't understand amps.

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post #41 of 56 Old 10-23-2012, 07:28 PM
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thanks

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post #42 of 56 Old 10-23-2012, 08:23 PM
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So will a not so good amplifier drop power during technical passages? If so, what part of the speaker would be more likley to take the biggest impact? Would it be the bass drivers since they physically move more?

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post #43 of 56 Old 10-24-2012, 04:47 AM
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Originally Posted by bthrb4u View Post

So will a not so good amplifier drop power during technical passages?

A good amplifier will not significantly lose its ability to reach maximum power during challenging passages.

Because modern amplifiers are rated and tested with sine waves which are far, far (between 5 and 10 times) more difficult signals than real-world music, they have significant hidden power reserves. This is even true of AVRs that show a significant power loss on the test bench when all channels are maxed out at the same time in sine wave tests. Bench tests are also based on resistive loads which again place unrealistically difficult loads on amplifiers.
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If so, what part of the speaker would be more likley to take the biggest impact? Would it be the bass drivers since they physically move more?

First off, in a well-designed audio system the really big bass drivers aren't powered by the AVR. They are best implemented as subwoofers that have their own power amplifiers.

However when using so-called full-range speakers (which almost always fall short of the bass performance of good subwoofers) yes, the low frequency drivers generally end up getting a disproportionately large amount of power. However, it is safe to predict that there will be no hidden losses of power to drive them.

Most audiophiles have no idea about how much power their systems actually need. There are many different influences that come into play when an audio system is cranked up. For example few audiophiles realize that their ears can be major sources of audible distortion when they are playing their systems very loud. If your listening room is excessively reverberant, listening to recordings at high levels can be unpleasant due to the excess reverberation. Loudspeaker systems are almost always larger sources of distortion than the amplifiers that drive them.

In pro audio, most amplifiers have either power indicators in the form of a row of fast-acting LEDs that represent different power levels, or at least a LED that flashes when the amplifier is clipping. These would be good tools for AVRs. I suspect that they are not common because most audiophile systems are overpowered, and they would never light up. A certain amount of audiophile money gets spent on ineffective additional amplification.

If your system actually needs more power, you need a lot more power than what you have. Most AVRs have about 100 wpc which is actually a lot of power. If you want your system to play cleanly at twice the SPL and have the robust speakers to pull it off, then you need to look at amplifiers in the 1,000 wpc range. Few audio dealers actually have products like this to sell, so they give a song and dance that minimizes and even libels the performance of the AVR.

On another forum I saw a dealer claim that all of the upscale rebranded AVRs from a certain manufacturer had 20% larger power supplies. Well first off, 20% more power is like spitting in the wind. It would be barely audible at best. Secondly research of the subject found that according to service manuals, the upscale and standard AVRs had the identical same power amp circuitry. Thirdly, they weighed the same. Fourthly the UL specs for the AVRs showed identical maximum power drain. Shall we be generous and say that the dealer was poorly informed? ;-)
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post #44 of 56 Old 10-27-2012, 01:53 PM
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Originally Posted by arnyk View Post

Most audiophiles have no idea about how much power their systems actually need. There are many different influences that come into play when an audio system is cranked up. For example few audiophiles realize that their ears can be major sources of audible distortion when they are playing their systems very loud.

I do.. ..My McIntosh Integrated has wattage meters (claimed by McIntosh, and confirmed independently, to have an accuracy of > 95% of the peak power output with only a single cycle of a 2,000Hz tone burst) and I can tell you that I seldom crest 10 - 15 watts. ..Most of time, I listen using only 4-5 watts of power. ..Listening to music with peaks that sail just beyond 20 watts is damn near painful and is likely to provoke the wrath of neighbors. Granted, my speakers are quite efficient (92 db) and room fairly reverberant. So I think Arnyk is correct... Even if an AVR receiver is a bit less robust power-wise when compared to a boutique brand 2-channel amp, chances are it still has wayyy more power than you'll actually need, no matter what speakers you use.
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post #45 of 56 Old 10-29-2012, 11:51 PM
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Harmon Kardon HK990 looks like about the best 2-channel option these days.
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post #46 of 56 Old 11-07-2012, 02:11 PM
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I think my hk 990 sounds better than my 3490. Maybe I'm delusional but it does sound better ro me. A lot of it is probably the digital crossover that integrates the sub a lot better than the passive filter I used with the hk 3490. The noise floor is definitely lower on the headphone out, at the very least. No hiss and cleaner sound due to the dedicated headphone amp. The 3490 powers phones with the main amp and some resistors. Not bad but a bit noisy and noise quite as clear as the texas instruments IC the 990 uses.

pc> hk 990> ascend acoustics raal towers\rythmik f15
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post #47 of 56 Old 11-08-2012, 05:56 AM
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Originally Posted by syd123 View Post

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Originally Posted by arnyk View Post

Most audiophiles have no idea about how much power their systems actually need. There are many different influences that come into play when an audio system is cranked up. For example few audiophiles realize that their ears can be major sources of audible distortion when they are playing their systems very loud.

I do.. ..My McIntosh Integrated has wattage meters (claimed by McIntosh, and confirmed independently, to have an accuracy of > 95% of the peak power output with only a single cycle of a 2,000Hz tone burst) and I can tell you that I seldom crest 10 - 15 watts. ..Most of time, I listen using only 4-5 watts of power. ..Listening to music with peaks that sail just beyond 20 watts is damn near painful and is likely to provoke the wrath of neighbors. Granted, my speakers are quite efficient (92 db) and room fairly reverberant. So I think Arnyk is correct... Even if an AVR receiver is a bit less robust power-wise when compared to a boutique brand 2-channel amp, chances are it still has wayyy more power than you'll actually need, no matter what speakers you use.

I think that it wouldn't cost that much, and it would be very helpful if the majors put just a simple clipping light on their AVRs.

If I had the ears of their marketing people I'd pitch them as "Buy more power" indicators. ;-)

Most of the pro audio amps have at least some kind of clipping indicator, and many have at least basic level indicators with useful response times.

McIntosh of course can nail it when they do meters, and IME they have done meters right for a long time. Looks, performance, they do it!
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post #48 of 56 Old 11-17-2012, 04:46 AM
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HI there! I am looking to buy a mini stereo which may turn into home theatre in the future.It's primary function will be for the use of my iPod, with movies secondary.I do not use CD's or records.I like to listen to hard rock/grunge and also accoustic. The room is 10-12 square metres with hard floors and a 2.5 metre high ceiling.I am looking at getting the Marantz NR 1603 and pair it with B+W 685's.Is this a suitable combination? I am also looking at the Monitor Audio BR-2s,and the KEF Q300's . If not what other amp /speaker combination do you recommend? I have a budget of around $1000 .It's primary function will be for the use of my iPod, with movies secondary.I do not use CD's or records.I like to listen to hard rock/grunge and also accoustic. I am in China so my options are limited to what I can see in the few HiFi stores here or on taobao.com (Chinese ebay).Any suggestions and help is greatly appreciated.

Speaker-wise I would say "none of the above," because none of them have good midrange performance. In the KEF Q-series lineup, the Q100 and Q500 are so much better-sounding than the Q300 and Q700. The reason is that with the 5" driver you get even midrange coverage, whereas with the 7" woofer and same tweeter you get the "hi-fi" sound that comes from uneven midrange coverage. (The Q900 is a different beast. It has a much bigger tweeter and also very even coverage.)

The Marantz box seems like the only game in town for what it is: a slim AVR with any kind of useful room correction software.
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I understand what you mean about speaker manufactures being scared. I didn't say all.
The reason i say it's easier to find a Dac is because speakers all have certain characteristics to them like the B&W CM9's have really rich sweet forward mids. Some amplifiers might dry these mids out and change the characteristics of the mids. Some might make them more rich.

You're actually right, to a degree. The magic words are "output (or 'source') Impedance." A crappy amp will have a low output impedance, which then interacts with the speaker's own elements to mess up the frequency response. For example, here is an example of a low-fidelity garbage amp from a so-called high end company that costs almost $10k a pair. Note that into the Kantor simulated speaker load Stereophile uses, there are over 2dB in FR swings where the ear is very sensitive. By contrast, a competently-designed amp will have very high output impedance, resulting in basically flat FR into actual speakers. See here for an example of how a competently-designed amp measures into the simulated load. AVR amps (except some Class D amp models) look more like the Bryston than the CJ.

Another reason more sensitive speakers are more revealing of problems down the chain is because any noise in the system is louder through more sensitive speakers than through less sensitive speakers. (My personal test for any amp used to drive anything but subs is to take a cheap ~100dB horn tweeter, attach it to each output in sequence, and see if anything is audible from arm's length away. If it is, I reject the amp as too noisy. The most recent amp to fail the test was a Rotel box with Icepower amps. The most surprising amp to pass it was the 250W/8Ω, 500W/4Ω 8-channel ElectroVoice Class D "pro" amp I use to run my multisub system. (I guess the Germans do still know a thing or two about engineering.)

However, note that even a perfect amp will pass along any noise in the signal ahead of it. Usually, the problem is not with an individual component, but with gain matching somewhere in the chain. That is another powerful argument for the modern paradigm of digital sources into a one-box DAC/processor/amp (an "AVR"), because then gain-matching is a non-issue.
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i, with my inexperience, also thought they were voiced too to have differences in the sound.

Some are tailored to be low-fidelity devices, in fact. One example known to me is the old "Butler Tube Driver" car amps, which had a boosted midrange that was falsely attributed to a tube in the input circuitry. (The "tube sound" knob on the amp was just a 1-band midrange boost.) But most modern audio amps are designed to be high-fidelity devices.
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Originally Posted by bthrb4u View Post

I read that speakers like electrostats need more current than voltage.
Can anyone chime in on this and what an amp needs to be a good amp for them.

Stats tend to need beefier amps, because their impedance drops as frequency increases. But pretty much any modern separate amp will do.
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Originally Posted by bthrb4u View Post

Also why is it that some people say that some speakers need high voltage to "really open them up"

More often than not, because the speakers are voiced a bit bass-shy. So they don't "open up" (i.e. sound perceptually well-balanced) until they're played louder.

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Originally Posted by arnyk View Post

[***Most audiophiles have no idea about how much power their systems actually need. There are many different influences that come into play when an audio system is cranked up. For example few audiophiles realize that their ears can be major sources of audible distortion when they are playing their systems very loud. If your listening room is excessively reverberant, listening to recordings at high levels can be unpleasant due to the excess reverberation. Loudspeaker systems are almost always larger sources of distortion than the amplifiers that drive them.

Arny, I'm curious what you think of the "how much power do you need" test here. It strikes me as a pretty elegant way of determining actual requirements.
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I think my hk 990 sounds better than my 3490. Maybe I'm delusional but it does sound better ro me. A lot of it is probably the digital crossover that integrates the sub a lot better than the passive filter I used with the hk 3490. The noise floor is definitely lower on the headphone out, at the very least. No hiss and cleaner sound due to the dedicated headphone amp. The 3490 powers phones with the main amp and some resistors. Not bad but a bit noisy and noise quite as clear as the texas instruments IC the 990 uses.

Amps do have different levels of noise, and the 990 not only has better crossovers but also room correction. So I'd expect it, if the RC is competently used, to sound better than HK's more basic integrated.

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post #49 of 56 Old 11-17-2012, 01:33 PM
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Originally Posted by DS-21 View Post

You're actually right, to a degree. The magic words are "output (or 'source') Impedance." A crappy amp will have a low output impedance, which then interacts with the speaker's own elements to mess up the frequency response. For example, here is an example of a low-fidelity garbage amp from a so-called high end company that costs almost $10k a pair. Note that into the Kantor simulated speaker load Stereophile uses, there are over 2dB in FR swings where the ear is very sensitive. By contrast, a competently-designed amp will have very high output impedance, resulting in basically flat FR into actual speakers. See here for an example of how a competently-designed amp measures into the simulated load. AVR amps (except some Class D amp models) look more like the Bryston than the CJ.
.

You sure about that?

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post #50 of 56 Old 11-17-2012, 03:11 PM
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Originally Posted by DS-21 View Post

You're actually right, to a degree. The magic words are "output (or 'source') Impedance." A crappy amp will have a low output impedance, which then interacts with the speaker's own elements to mess up the frequency response. For example, here is an example of a low-fidelity garbage amp from a so-called high end company that costs almost $10k a pair. Note that into the Kantor simulated speaker load Stereophile uses, there are over 2dB in FR swings where the ear is very sensitive. By contrast, a competently-designed amp will have very high output impedance, resulting in basically flat FR into actual speakers. See here for an example of how a competently-designed amp measures into the simulated load. AVR amps (except some Class D amp models) look more like the Bryston than the CJ.
.

You sure about that?

Hopefully not, because he's got it bass ackwards.

What I think he meant to say is:

A crappy amp will have a high output impedance, which then interacts with the speaker's own elements to mess up the frequency response.

Looking at his example, the CJ amp has a far higher equivalent source impedance than the Bryston.
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post #51 of 56 Old 11-18-2012, 01:07 AM
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Originally Posted by arnyk View Post

Hopefully not, because he's got it bass ackwards.

What I think he meant to say is:

A crappy amp will have a high output impedance, which then interacts with the speaker's own elements to mess up the frequency response.

Looking at his example, the CJ amp has a far higher equivalent source impedance than the Bryston.

Yes, that's what I actually meant. Right concept, but I'm bad with directions. smile.gif

Thanks for the correction.

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post #52 of 56 Old 12-12-2012, 09:03 AM
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Hi all,
I am planning to get a pair of R300 and looking for an amplifier that can provide the best performance with. I have 3 candidates that all include a DAC which is important for me since I want to use my blueray reader Sony BDP S370 as a CD drive.
- Harman Kardon HK 990, for the great dynamic that it can provide (1400 euros)
- Pioneer A-70, for its quality/price ratio (1000 euros)
- Exposure 2010s2, for its audiophile character (1150 euros)

I mostly listen vocal jazz and classical music, as well as want to use it as home cinema audio system. I like the tube-sound, warmness for jazz with good bass, yet precision and clearness for classicals.
I unfortnately did not have an opportunity to listen R300 with these amplifiers.
I would like to ask you if you have any experience with these ampliifers and/or if you could give me some recommendations on what I should expect to get with these combinations.
Many thanks in advance.
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post #53 of 56 Old 02-07-2013, 01:23 PM
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Just my personal experience my old Onkyo 806 in pure audio via analouge definitly sound much much wrose then my 2nd hand Nad C352 with same room, speaker, volume measure by SPL meter and everything.
So much so even my mum can pick it up just a minute into a song.
And sub, I will never use a sub after I got a good deep floor standing speaker and hear them side by side at the same time.
Playing electronic music and testing tone with same amplifer/source at the same time the sub is so slow it's not funny.
I was using Jamo E7 10" seal sub and Rythmik F12 12" seal servo Both should be the fastest style of sub.
But they were so slow compare to Quadral M4 I can hear the delay in between the beats even some beat was missing.
On top they sound so much muddier than floor stander with same everything.
I am no expert, and I don't think you need to pay 10s of 100s for good music but AVR and sub are not good solusion.
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post #54 of 56 Old 02-07-2013, 02:41 PM
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Quote:
Originally Posted by sasami View Post

...
Playing electronic music and testing tone with same amplifer/source at the same time the sub is so slow it's not funny.
I was using Jamo E7 10" seal sub and Rythmik F12 12" seal servo Both should be the fastest style of sub.
But they were so slow compare to Quadral M4 I can hear the delay in between the beats even some beat was missing.
....

The reason some of the beats were missing is due to the slowness of the sub. You simply didn't wait long enough!!
Give it a few minutes and it will remember to add in those missing beats.






Post of the year nominee for unintended hilarity.

For every new thing I learn, I forget two things I used to know.
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post #55 of 56 Old 02-09-2013, 08:16 AM
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Quote:
Originally Posted by sasami View Post

Just my personal experience my old Onkyo 806 in pure audio via analouge definitly sound much much wrose then my 2nd hand Nad C352 with same room, speaker, volume measure by SPL meter and everything.
So much so even my mum can pick it up just a minute into a song.
And sub, I will never use a sub after I got a good deep floor standing speaker and hear them side by side at the same time.
Playing electronic music and testing tone with same amplifer/source at the same time the sub is so slow it's not funny.
I was using Jamo E7 10" seal sub and Rythmik F12 12" seal servo Both should be the fastest style of sub.
But they were so slow compare to Quadral M4 I can hear the delay in between the beats even some beat was missing.
On top they sound so much muddier than floor stander with same everything.
I am no expert, and I don't think you need to pay 10s of 100s for good music but AVR and sub are not good solusion.

Sounds to me like a placement/room tuning problem, not a subwoofer problem.
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post #56 of 56 Old 02-09-2013, 08:33 AM
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Quote:
Originally Posted by DS-21 View Post


Quote:
Originally Posted by arnyk View Post

[***Most audiophiles have no idea about how much power their systems actually need. There are many different influences that come into play when an audio system is cranked up. For example few audiophiles realize that their ears can be major sources of audible distortion when they are playing their systems very loud. If your listening room is excessively reverberant, listening to recordings at high levels can be unpleasant due to the excess reverberation. Loudspeaker systems are almost always larger sources of distortion than the amplifiers that drive them.

Arny, I'm curious what you think of the "how much power do you need" test here. It strikes me as a pretty elegant way of determining actual requirements.

Agreed.

I think that good thinking went into this test. I might quibble with it, but it can clearly develop useful evidence.

In this test the maximum voltage from a 100 wpc AVR would be about 30 volts, so anything under 7.5 volts indicates no trouble found.

Here are the statistics for the summary over 200 responses (probably indicative of or a little higher than of what most people reading this thread on AVS would obtain)

2 volts or less 94 38.21%
Between 2-5 volts 86 34.96%
Between 5-10 volts 29 11.79%
Between 10-20 volts 15 6.10%
Over 20 volts. 22 8.94%

I would estimate that over 80% of the people who ran the test obtained results that indicated that a typical 100 wpc AVR would do the job for them just perfectly. I suspect that most of the people who ran the test were in doubt, so the actual percentage of audiophiles who would are OK with their existing AVR is > 80%.

About 10% would need an amp that was rated at more than 800 watts to meet their need.

Almost every AVS post about an power amp upgrade for an AVR involved an amp in the 150-600 watt range, and that would apply to about 10% of the situations. So, about half of the situations where the AVR wouldn't actually do the job needed an amp > 800 wpc. . IOW about half the people who actually need a larger amp are for sure getting the wrong (way too small) amp.

I will leave it to the readers to contemplate about what happens when you hook a >800 wpc power amp up to a typical pair of large audiophile speakers and actually use that puppy for what it was designed to do. Not pretty! :-(
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