Do all amplifiers sound the same thread

[PENG]

By transient attack, do you mean the rise time of the amplitude? This is really interesting! I guess that makes sense for a wind or bowed instrument, but I would think a percussive instrument would be almost as fast as the pitch allows.

I'll put my money on the triangle as fastest sound of a common instrument!

I wonder how plucked compares to hit? The top end of a harp seems pretty fast!

Neat stuff!

You are right on the money about everything. I can post the link but rather not as I am still power googling. You can just google for transients in music... or something like that.. I focus on the more academic type of research papers, rather than people talking on forums such as ours.

 

[Calvin Hobbes]

You're so focused on your own conclusion that you're missing my point altogether. I'm not talking about 110db average levels, I'm talking about 110db peaks for a particular instrument being played a certain way. Frankly, I don't listen with 110db peaks on my system, ever. Well, just that once when I was trying to truly simulate my wife's drum kit, but that was it. If I get really rambunctious I listen to 102-104db peaks on well-recorded contemporary jazz, but the average levels are worst-case in the mid-high 80s, though my more normal listening levels are high 70s-low 80s, and with an 80db average I see peaks on the OmniMic in the 95-100db range, and mostly in the 90s.

My point is, PENG, that if you want to reproduce live music levels for some instruments, and saxophones and trumpets fall into this category incidentally, you're going to need more than 20W of peak power into 83db/w sensitive speakers. You can make all the fun you want of this and my statements, based on some measurements that you feel satisfy your own particular needs, and I'm only pointing out that there are other environments, systems, and considerations where more power is called for, and necessary to avoid clipping.

The impedance at 1500 hz is 10 ohms. Would you need that much power to generate 110 db at that frequency?

 

[mtrycrafts]

Oh boy the madness is over, now off to the mountains with the family for Christmas.

Merry Christmas all

And the same to you. Just take your GPS so you can find your way home and back to AH
We'll take care of the madness, not to worry.

 

[mtrycrafts]

... In regard to your example of needing 500W for the 110 dB peaks ....

I would think that those high powered peaks would take advantage of an amp's dynamic headroom and would not need that continuous power rating, no?
I think the duration time used for such peak testing is 20 ms.

 

[Irvrobinson]

The impedance at 1500 hz is 10 ohms. Would you need that much power to generate 110 db at that frequency?

No. Good catch. I was too consumed arguing with PENG. Still, it'll be more than 20 watts.

 

[mtrycrafts]

The really short peaks are easily handled.. Its the longer duration peaks that reek havoc on amps. I wonder, can the human ear even detect a peak of 0.00000000000X seconds?

And this is where the amp's slew rate may come into play?
Usually about 20V/us would get up to rail max in a few us. Now I am wondering what is the slew rate of those 500 watt and higher amps? Can they get up there in time???

 

[PENG]

No. Good catch. I was too consumed arguing with PENG. Still, it'll be more than 20 watts.

I was going to say exactly (I might have said....still,...much more than 20 watts...) what you just said but I know it was yours to respond.

 

[mtrycrafts]

True. But most of us cannot handle sustained long duration peaks of 100+ dB at the listening position. We would just turn down the volume due to excruciating pain.

Some of us, me included, but I have read posts where a few like ear bleeds

So the amps wouldn't be asked to handle what we can't handle ourselves.

Oh, how kind of you to be so considerate of the amps

 

[jostenmeat]

By transient attack, do you mean the rise time of the amplitude? This is really interesting! I guess that makes sense for a wind or bowed instrument, but I would think a percussive instrument would be almost as fast as the pitch allows.

I'll put my money on the triangle as fastest sound of a common instrument!

I wonder how plucked compares to hit? The top end of a harp seems pretty fast!

Neat stuff!

I'm not even pretending to be following the details of the recent discussion, though I do suspect a lot of this really is "academic" precisely because I agree that power handling and/or heat dissipation of the drivers really are the weak link (if any given high powered transient attacks are to be repeated for any length of time).

I'd like to offer some different perspective. First of all, transients vs avg with percussion, well without a trace of a doubt, the highest avg spl level I've ever experienced in a concert hall featuring acoustical music was at a percussion event, with the music of Messiaen to be precise. It was a big hall, a very dead one too, I must have been a solid +100ft away, and for a lot it I was plugging both ears closed with my fingers/hands. The amount of SPL those gongs can sum up just needs to be experienced to be believed because you just can't imagine it otherwise, well I couldn't have anyway. The huge room was seriously pressurized, it was palpable.

Also, the piano is a percussive instrument; it uses a whole bunch of hammers that strike straight down on the strings. I believe this is why the piano is SO DIFFICULT to reproduce well. With my HT speakers in particular, it has been my impression for a while now that this is the hardest thing to do for them. A piano probably represents highs in both avg and transient. Dampers lifted by pedal, striking like crazy; transients + resonance. (On a different note, another revealing thing about the piano is that it has the most consistent "tone" from top to bottom; keyboards in general are the most "balanced" instruments there are.) Alright, carry on.

 

[Irvrobinson]

And this is where the amp's slew rate may come into play?
Usually about 20V/us would get up to rail max in a few us. Now I am wondering what is the slew rate of those 500 watt and higher amps? Can they get up there in time???

50-100 volts per microsecond. ATI says 70v/us for my amp. The monster Krell 900e monoblock is rated for 90v/us.

 

[PENG]

And this is where the amp's slew rate may come into play?
Usually about 20V/us would get up to rail max in a few us. Now I am wondering what is the slew rate of those 500 watt and higher amps? Can they get up there in time???

Wow, another good point, talk about putting things in perspective..

 

[PENG]

General Acoustics

Start thinking about the "reverb time" also..

 

[PENG]

for any length of time).

I'd like to offer some different perspective. First of all, transients vs avg with percussion, well without a trace of a doubt, the highest avg spl level I've ever experienced in a concert hall featuring acoustical music was at a percussion event, with the music of Messiaen to be precise. It was a big hall, a very dead one too, I must have been a solid +100ft away, and for a lot it I was plugging both ears closed with my fingers/hands. The amount of SPL those gongs can sum up just needs to be experienced to be believed because you just can't imagine it otherwise, well I couldn't have anyway. The huge room was seriously pressurized, it was palpable.

Even in my relatively small rooms it would be hard to get enough Watts to reproduce realistic concert hall live performance sensations and I am only talking about unamplified classical music concerts. Having said that, long before reaching the point of enough watts, the voice coils of my speakers would have melted down.

 

[jostenmeat]

Even in my relatively small rooms it would be hard to get enough Watts to reproduce realistic concert hall live performance sensations and I am only talking about unamplified classical music concerts. Having said that, long before reaching the point of enough watts, the voice coils of my speakers would have melted down.

I too was only speaking of unamplified music.

 

[ahblaza]

Are we done yet Merry Christmas with no clipping or dipping or sipping...

 

[JerryLove]

Even in my relatively small rooms it would be hard to get enough Watts to reproduce realistic concert hall live performance sensations and I am only talking about unamplified classical music concerts. Having said that, long before reaching the point of enough watts, the voice coils of my speakers would have melted down.

At what distance? I've been in the pit, and I've been back in the audience where old people with crinkly plastic around their hard candies were making the orchestra hard to hear.

But yes. An orchestra is dozens of sound sources. It's diffuse. I'd think your best choice would be with lots of sound-reinforcement speakers.

 

[mtrycrafts]

General Acoustics

Start thinking about the "reverb time" also..

Yep, whoever said it was simple and easy.

 

[3db]

Amps with high slew rates will be better able to track fast transients imparting a more real sound than a transient that is smeared. That will make one amp sound better than another but its not that simple. Again, one has to look at how hard the amp is being driven (what volume and at what load) at the moment that the transient appears. If the amp is not being taxed, most will easily follow the transients of music or a film score.

The one thing I'm curious about with all this talk about live equipment is this...how much of this transient information is actually captured in a recording without being limited in amplitude? Maybe amps all sound the same when not being overdriven is because of the recording and not the ampilifiers' behaviour.

Amplifiers are pretty basic and simple. They are not complicated compared to (borrowing this line from Monkish) measuring Neutrinos, the bending of time-space, subatomics in their quantum state...etc Any competent measurements ( not purely resisitive measurements) will tell us how an amplifier will behave. Not all measurements are audible or detectable by the human ear no matter how much some of us want to say "I have golden ears"

 

[PENG]

Maybe amps all sound the same when not being overdriven is because of the recording and not the ampilifiers' behaviour.

Amplifiers are pretty basic and simple. They are not complicated compared to (borrowing this line from Monkish) measuring Neutrinos, the bending of time-space, subatomics in their quantum state...etc Any competent measurements ( not purely resisitive measurements) will tell us how an amplifier will behave. Not all measurements are audible or detectable by the human ear no matter how much some of us want to say "I have golden ears"

You know my opinion/feeling on this one already don't you? Why do you think I started a thread to collect "High quality sound albums.."? Yep, that's what i believe, once you cross the line from higher midrange and above AVR/AMPs and players (speakers/room acoustics aside), the biggest improvements would come from the recordings themselves. Just my 0.00000001 cents.

 

[3db]

You know my opinion/feeling on this one already don't you? Why do you think I started a thread to collect "High quality sound albums.."? Yep, that's what i believe, once you cross the line from higher midrange and above AVR/AMPs and players (speakers/room acoustics aside), the biggest improvements would come from the recordings themselves. Just my 0.00000001 cents.

Lets round that up to the nearest cent

However, as a music lover, don't let bad recordings sway you away from good goups/music....ie like teh Raveonettes. Awesome band!! Poor recording.... still love it.