All amps sound the same??? (Read Inside)

[costanza]

Well that was an accoustic problem, not a fault of the receiver.

I'm gonna take the Denon and my diy comparison cables to this room with the Definitive speakers and see if the Denon sounds as bad as the Panasonic.

 

[mtrycrafts]

Amps might have different distortion characteristics--how the even and odd order distortions break down, as well as the amplitude of individual distortions--higher order distortions sound considerably worse than lower order distortions at the same SPL.

But I don't think these characteristics will truly manifest unless you are listening at fairly high levels, say 85db+

Yes, but. If the THD is well below the threshold of detection, a higher order distortion must be much less than the THD as it too is part of that number. So, how might it be audible?
85 dB is not that loud and is about 1 watts of power at most.

 

[ichigo]

Yes, but. If the THD is well below the threshold of detection, a higher order distortion must be much less than the THD as it too is part of that number. So, how might it be audible?
85 dB is not that loud and is about 1 watts of power at most.

85dB average. Assuming it's not pop music the louder passages could be colored more as the amp begins to strain. Just 3dB more will be twice the power remember. Dynamic range for better recordings can be quite high. Say Tchaikovsky 1812 Overture is over 30dB--you would need something like 2,000W/channel at the peaks without clipping.

 

[mtrycrafts]

85dB average. Assuming it's not pop music the louder passages could be colored more as the amp begins to strain. Just 3dB more will be twice the power remember. Dynamic range for better recordings can be quite high. Say Tchaikovsky 1812 Overture is over 30dB--you would need something like 2,000W/channel at the peaks without clipping.

Oh, but is that 30dB from 85 or something else? Perhaps, at 85, you are in reality, partly into that 30 dB range, most likely that is the case already. 115 dB peaks? Perhaps in a live performance with cannons close by recorded at the cannons? Telarc's 1812 used digital recording at the time with period cannons, blew out some windows. What is the peak level? Does it approach 0db full scale anyplace on the recording? A good question to ask Telarc, no? Guessing is just that.

Oh, can your speakers take 115 dB spl? At what THD? 20%?

 

[PENG]

Oh, but is that 30dB from 85 or something else? Perhaps, at 85, you are in reality, partly into that 30 dB range, most likely that is the case already. 115 dB peaks? Perhaps in a live performance with cannons close by recorded at the cannons? Telarc's 1812 used digital recording at the time with period cannons, blew out some windows. What is the peak level? Does it approach 0db full scale anyplace on the recording? A good question to ask Telarc, no? Guessing is just that.

Oh, can your speakers take 115 dB spl? At what THD? 20%?

My Denon has no trouble with 1812 overture Telarc CD80041. No strain no audible clipping and you are right about 30 dB from what?? People do tend to exaggerate things don't they?

 

[lsiberian]

My Denon has no trouble with 1812 overture Telarc CD80041. No strain no audible clipping and you are right about 30 dB from what?? People do tend to exaggerate things don't they?

Most baseline listening levels are 60db. 70db for movies. 30db would have you at 100, but a little clipping of something that violent probably wouldn't be noticeable.

 

[PENG]

Most baseline listening levels are 60db. 70db for movies. 30db would have you at 100, but a little clipping of something that violent probably wouldn't be noticeable.

True it would be hard to tell whether the sound of the cannon shots clipped the amp even if it did slightly. I don't remember recording anything like 30 dB swing from 75 db of average listening level. I do remember hitting up to 105 dB even with my badest CDs, and it made no difference in my HT room whether I used the Denon AVR, or the 4B SST. I did find it hard to determine what was the based level for something like the 1812. With Diana Krall's stuff it was easy, the min/max I recorded once in my room was 75/86 dB, that is 11 dB between min and max.

 

[PENG]

You guys got me curious so I decided to take some measurements.

Telarc CD-80041

In the beginning when the cellos are playing......50 to 68, avg. 55? (guessimate)

When the bass drum/timpani gets involved........60's to 78, avg. 60's?

Cannon fires................................................80 to 86, avg. 83

Bells banging after the cannons.......................77 to 79, avg. 78 (steady)

I could not say what my listening level was because it was all over the map. One of these days I will get the instruments I need and plot the instantaneous SPL vs time graph.

Suffice to say though, you get easily 36 dB of range from the quietest moment (with just some strings in the beginning) to the loudest moment. So if you pick 70 as what you may call the listening level, you need about 20 dB of headroom to be save. Most mid range AVR (can be demonstrated mathematically) should be handle it without audible clipping in suitable rooms.

My comments are obviously based on using my specific equipment and the Telarc CD-80041 that supposedly used real cannons, in my specific room. Your mileasge may vary.

Case in point, this Telarc CD claims the cannon shots go from the initial ignition's 2000 to 3000 hz to the follow up boom's 6 hz that we can't hear, but probably could feel if our electronics and speakers can go that low, that seems to be more difficult to overcome than the concerns about headrooms and dynamic ranges..

 

[Pyrrho]

You guys got me curious so I decided to take some measurements.

Telarc CD-80041

In the beginning when the cellos are playing......50 to 68, avg. 55? (guessimate)

When the bass drum/timpani gets involved........60's to 78, avg. 60's?

Cannon fires................................................80 to 86, avg. 83

Bells banging after the cannons.......................77 to 79, avg. 78 (steady)

I could not say what my listening level was because it was all over the map. One of these days I will get the instruments I need and plot the instantaneous SPL vs time graph.

Suffice to say though, you get easily 36 dB of range from the quietest moment (with just some strings in the beginning) to the loudest moment. So if you pick 70 as what you may call the listening level, you need about 20 dB of headroom to be save. Most mid range AVR (can be demonstrated mathematically) should be handle it without audible clipping in suitable rooms.

My comments are obviously based on using my specific equipment and the Telarc CD-80041 that supposedly used real cannons, in my specific room. Your mileasge may vary.

Case in point, this Telarc CD claims the cannon shots go from the initial ignition's 2000 to 3000 hz to the follow up boom's 6 hz that we can't hear, but probably could feel if our electronics and speakers can go that low, that seems to be more difficult to overcome than the concerns about headrooms and dynamic ranges..

With modern electronics, there is no difficulty in going down to 6 Hz (if the engineers desired to give that to you, though sometimes such frequencies are purposely filtered out). The difficulty is getting a speaker that can do that, as even quality subwoofers that are a good value at a thousand or a couple of thousand dollars are not going to be giving you much at 6 Hz. Fortunately, it is not terribly important for music, and feeling the room vibrating can be achieved with higher frequencies than that.

 

[PENG]

With modern electronics, there is no difficulty in going down to 6 Hz (if the engineers desired to give that to you, though sometimes such frequencies are purposely filtered out).

Many CD players, especially the older ones cannot go that low, or as you said, filtered out.

 

[mtrycrafts]

You guys got me curious so I decided to take some measurements.

Telarc CD-80041

In the beginning when the cellos are playing......50 to 68, avg. 55? (guessimate)

When the bass drum/timpani gets involved........60's to 78, avg. 60's?

Cannon fires................................................80 to 86, avg. 83

Bells banging after the cannons.......................77 to 79, avg. 78 (steady)

I could not say what my listening level was because it was all over the map. One of these days I will get the instruments I need and plot the instantaneous SPL vs time graph.

Suffice to say though, you get easily 36 dB of range from the quietest moment (with just some strings in the beginning) to the loudest moment. So if you pick 70 as what you may call the listening level, you need about 20 dB of headroom to be save. Most mid range AVR (can be demonstrated mathematically) should be handle it without audible clipping in suitable rooms.

My comments are obviously based on using my specific equipment and the Telarc CD-80041 that supposedly used real cannons, in my specific room. Your mileasge may vary.

Case in point, this Telarc CD claims the cannon shots go from the initial ignition's 2000 to 3000 hz to the follow up boom's 6 hz that we can't hear, but probably could feel if our electronics and speakers can go that low, that seems to be more difficult to overcome than the concerns about headrooms and dynamic ranges..

Obviously you need to turn up the volume a bit. 86 dB on the cannons? Wuss. Get it to 105
Some moons ago when I played with this, the sub amps were close to 150 watts each; impressive sounds.

 

[PENG]

Obviously you need to turn up the volume a bit. 86 dB on the cannons? Wuss. Get it to 105
Some moons ago when I played with this, the sub amps were close to 150 watts each; impressive sounds.

Of course I did so before and it felt better for sure. This time I turned it down just to minimize the chance people like you might say that my gear don't have enough juice to go that high blablabla.... See, so far no one is saying perhaps my gear could not hit higher than 86 dB in my small room hence compressed everything skewing the results............

 

[highfigh]

85dB average. Assuming it's not pop music the louder passages could be colored more as the amp begins to strain. Just 3dB more will be twice the power remember. Dynamic range for better recordings can be quite high. Say Tchaikovsky 1812 Overture is over 30dB--you would need something like 2,000W/channel at the peaks without clipping.

The vinyl version is less compressed than the CD because at 0dB, digital recording basically hits a brick wall and if the level exceeds that, it goes bad, really fast. Before CDs came out, we would use the most demanding material to demo equipment and that included cassette/open reel tape recorders. When the cannon blasts came, the VU meters showed a 30db peak with the vinyl copy and the recording level needed to be adjusted accordingly, in order to avoid massive distortion at those points. When the Telarc CD came out, I noticed that the peak was only 20dB with the same brand of recorders with the same kind of metering and no compression of any type.

Also, if the SPL is 85dB and the listening position is 12' from the speakers, it's close to 6dB higher at 1m. Assuming 88dB/W/m speaker sensitivity and it's a relatively reverberant room, the free-field loss of 6dB for every doubling of distance will be somewhat reduced, but it's still not going to be operating at only 1W. If we use a 6dB drop at 4x the typical 1m measuring distance, the average power level would be 4W (3dB added for every doubling of power) and with a 20dB non-limited peak, the system will need to produce 400W. To produce the 30dB peak from an average of 4W, it needs to be able to produce 4000W.

The 'dynamic headroom' spec that began to be used in the '80s for consumer grade amplifiers required the peak to be sent to the amp when the amp was already at maximum rated output power and it was supposed to top out at a low number in terms of distortion. Some amps weren't able to produce a clean peak, at all. Some were able to double their power but most were somewhere in the middle.

Realistically, if the level isn't excessive, the peaks will usually sound clean enough and if not, it will definitely be audible. If they actually left the sub-20Hz information on the vinyl version, no stylus would have tracked it, so it was probably filtered. Since it's very unlikely that anyone out here in Consumer Audio Land had a system that would reproduce such low frequencies back in the late '70s/early '80s, there would have been no point in leaving it on any type of disc, vinyl or CD. Besides, if the speakers or subwoofer use a vented box, those frequencies won't be reproduced well, if at all. the woofer(s) are not well damped below the port tuning frequency and at 6Hz, it/they would be flapping in the breeze.

 

[AJinFLA]

I'm gonna take the Denon and my diy comparison cables to this room with the Definitive speakers and see if the Denon sounds as bad as the Panasonic.

Why bother when it's Class AB vs earlier Class D w/ gutless power supply (not to mention sighted and uncontrolled)?

Anyone who tells you that all amplifiers sound the same, is either a subjectivist strawman or technically illiterate.
Anyone who tells you that all amplifiers sound different, is an "audiophile" (by far the worst insult).

 

[lsiberian]

With modern electronics, there is no difficulty in going down to 6 Hz (if the engineers desired to give that to you, though sometimes such frequencies are purposely filtered out). The difficulty is getting a speaker that can do that, as even quality subwoofers that are a good value at a thousand or a couple of thousand dollars are not going to be giving you much at 6 Hz. Fortunately, it is not terribly important for music, and feeling the room vibrating can be achieved with higher frequencies than that.

Yeah but there is no way to isolate frequencies that low. IOTW the 10hz shake you might be hearing could be from the subway running beneath the studio. As far as I'm aware there are only 20hz chambers. I don't know of anything lower.

My sub can shake the room if I crank it and it's a sealed 12".

 

[PENG]

If we use a 6dB drop at 4x the typical 1m measuring distance, the average power level would be 4W (3dB added for every doubling of power) and with a 20dB non-limited peak, the system will need to produce 400W. To produce the 30dB peak from an average of 4W, it needs to be able to produce 4000W.

I wouldn't use 88 dB as the starting point at all, but you would be about right if you in fact listen at 88 dB level even during the 1st movement when only the cellos are on. For me, I would use 75 dB (as you say sitting 4m away) at the most, as the reference point for that CD. In my room I actually lost less than 6 dB from 4 m away but I agree with your number none the less.

 

[costanza]

I compared the Denon 2803 and Harman Kardon AVR 125 receivers last night with my little diy comparison cable setup. Both receivers were receving optical input, were "matched to MY satisfaction" in db according to my analog RS spl meter with pink noise, their tone controls were bypassed and the speakers were Primus 250's. I identified the HK 2 out of 2 times because it has an ever-so-slightly brighter top end. They were nearly identical to one another. I *think" the Denon may have had a more "rounded" bottom end, but I would need a little more listening to confirm that. The Denon is listed as having 2x the watts, but of course Denon measures 8 ohm at 1Khz/1 channel and HK measures 8 ohm at 20Hz-20Khz/all channels. Both use the "-db" to "+db" numbers on their volume controls, and with levels "matched to MY satisfaction" with pink noise, both receivers' displays were showing nearly the same volume level number. Interesting.

 

[jinjuku]

I compared the Denon 2803 and Harman Kardon AVR 125 receivers last night with my little diy comparison cable setup. Both receivers were receving optical input, were "matched to MY satisfaction" in db according to my analog RS spl meter with pink noise, their tone controls were bypassed and the speakers were Primus 250's. I identified the HK 2 out of 2 times because it has an ever-so-slightly brighter top end. They were nearly identical to one another. I *think" the Denon may have had a more "rounded" bottom end, but I would need a little more listening to confirm that. The Denon is listed as having 2x the watts, but of course Denon measures 8 ohm at 1Khz/1 channel and HK measures 8 ohm at 20Hz-20Khz/all channels. Both use the "-db" to "+db" numbers on their volume controls, and with levels "matched to MY satisfaction" with pink noise, both receivers' displays were showing nearly the same volume level number. Interesting.

I think that speaks to another prevailing thought:

Almost all amps sound alike.

I haven't heard an amp that has made a night and day difference in what the speakers were doing. Not in sound stage, separation, depth etc...

 

[mtrycrafts]

I compared the Denon 2803 and Harman Kardon AVR 125 receivers last night with my little diy comparison cable setup. Both receivers were receving optical input, were "matched to MY satisfaction" in db according to my analog RS spl meter with pink noise, their tone controls were bypassed and the speakers were Primus 250's. I identified the HK 2 out of 2 times because it has an ever-so-slightly brighter top end. They were nearly identical to one another. I *think" the Denon may have had a more "rounded" bottom end, but I would need a little more listening to confirm that. The Denon is listed as having 2x the watts, but of course Denon measures 8 ohm at 1Khz/1 channel and HK measures 8 ohm at 20Hz-20Khz/all channels. Both use the "-db" to "+db" numbers on their volume controls, and with levels "matched to MY satisfaction" with pink noise, both receivers' displays were showing nearly the same volume level number. Interesting.

I predicted two coin flips in a row 100% correctly Perhaps I am able to control the outcome?

The Denon measurement done with 20Hz to 20kHz would only take away about 10% to 15% of the power, not much of a difference.

 

[AcuDefTechGuy]

I predicted two coin flips in a row 100% correctly Perhaps I am able to control the outcome?

I 1-up you; I predicted not 2, but THREE coin flips in a row 100% correctly!