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Bandwidth question?

I am interested in the qualitative difference in sound betw amplifiers that have -3db roll off at 100khz vs -3db at 300khz. Thru the amps I have tried, I suspect increased bandwidth has more openness and transparency and hence a better sense of space sharing. At the same time, it is easier to screw up the sound due to noise (from components/AC/RF) or improper cartridge loading. I am not very certain of the correlation and interested in what you guys think?

In reviewing the measurement sections of stereophile, many amps with -3db at 100khz demonstrate subtle rounding of the edges when reproducing 10khz square waves. I don't listen to square wave so I don't know what that translate into.

I realize that some amps (Spectral or Soulutions) has very high bandwidth (MegaHz) to implement negative feedabck. I am not refering to that.
128x128glai
magfan
1,583 posts
 
Is the bandwidth thing the problem with 'd' amps? they drop like a rock somewhere around or just OVER 20khz in order to get rid of the switching noise. Early 'd' amps were also noted for RF effects. I once picked one up on a filling.
Going along with the steep frequency dropoff, which is also linked to load impedance with low impedance having a quicker dropoff, but you also apparently get some phase problems.

I'm saving my Pesos for a Pass integrated. (look for a website soon since i'll be accepting donations....'Pesos for Pass. org'. I'll buy it without even an audition. Just let me plug it in and give 'er a rip. Reasonable bandwidth, low feedback and near-impeccible square wave response. This won't be buying specs, either since virtually nobody who hooks 'em up to an appropriate speaker from SDFR to Panels has anything BAD to say about 'em.
kijanki's avatar
kijanki
4,428 posts
 
Magfan, my class D Rowland 102 has 5Hz-65kHz -3dB bandwidth but I'm saving my Pesos for Rowland 625 with small possible temporary setbacks in the future like divorce, bankruptcy and foreclosure.
magfan
1,583 posts
 
Right you are...
The open loop for the ASP500 module is 80khz@8 ohms and 60khz24ohms.
All at some specified tolerance.
Phase displacement is also noted......
orpheus10
8,668 posts
 

While you don't have to be a "rocket scientist" to know what you hear, you do have to be a scientist in order to explain what you hear.

"Harmonics" are what separates the "high end" from "midfi". For example, if the fundamental frequency is 25 HZ, the frequencies of the harmonics are 50 HZ, 75 HZ and 100 HZ. Although the amplitude of the harmonics decreases in order, they determine the quality of the sound.

When you go to a live event, these harmonics are quite audible; they give the violin that rich tone and timbre, they resonate with each guitar note. These harmonics are present as low level detail at home.

If you have been to a live event and had that sensation of a sound that was ringing right in your ear, that was due to harmonics.
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kijanki
4,428 posts
 
Orpheus10,

We're all talking harmonics here. I mentioned summing of harmonics twice while Al mentioned it also few times. Highest fundamental is around 8kHz (church organs) but most often it is only up to about 2kHz as it is shown in this interactive chart:

http://www.independentrecording.net/irn/resources/freqchart/main_display.htm

I noticed that Harp has absolutely incredible range - never expected that.
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