Which amplifier "style" would be best for complicated / symphonic music?

[Jonathan Bright]

And, for the fanatics, following on from that, why not use the RIAA time constants more creatively? Presumably only the bass section (<500c/s) needs the RIAA bass boost. Why subject the rest of the pre-amps to those frequencies? Use the 500c/s turn over as one 'order' of the low to mid cross over.
Cheers Jonathan

 

[scottjoplin]

Possibly, but I thought small signal amplification didn't have the same issues with IMD as large signal?

 

[Jonathan Bright]

You may be right. I'm not formerly trained (only 2 yrs Mech Eng) so can't comment with any authority. I was just intrigued with remarks by people like Ben Duncan (HFN/RR) some time ago (30yrs?) when he (and others) said that the subjective results of multi-amping exceeded the expected advantages. If so, I've just been pondering what might explain that. I think I recall reading that JLH thought lower IM increased the discernment of individual voices or instruments..........but pls don't quote me on that. I do know he thought regulated supplies in PA's gave tighter bass.

 

[scottjoplin]

It's certainly beneficial in power amps, and more so in speakers

 

[Jonathan Bright]

Hi scottjoplin and others.
The address below is to the very early JLH discrete pre-amp that I was thinking of. Its the first couple of paragraphs that may be relevant to the issue of this thread's poster's original question. (almost certainty got the apostrophes wrong in that sentence please forgive me ha ha)

http://www.keith-snook.info/wireles...rld-1969/Modular Pre-amplifier Design-DCD.pdf

 

[Extreme_Boky]

two of my guys , both having Dynaudio Contour - one of them 1.3 , other 1.8 - fed with Iron Pre and Babelfish J , were jaw dropping when they heard T-Bed iteration of Babelfish M25

Could you point me to a thread talking about/explaining the "T-Bed iteration of Babelfish M25"?

 

[Dennis Hui]

Try here:

Babelfish M25 , AKA M2 on steroids , AKA M2-XA25 bstrd

 

[PRR]

Its interesting that when Martin Colloms ('High Performance Loudspeakers') considers multi-amping speakers he lists the reduction in IM distortion in the various power amps as the FIRST benefit. .....

This is very significant when amps are driven to CLIPPING, as in PA systems.

Ideally there would be low/band-pass filters between amp and speaker, but even without them the narrower span in each amp (and speaker!) significantly reduces the spread of the hash.

And "ideally" we high-budget domestic hobbyists can always use amplifier(s) so big they never clip, so this point is lessened.

 

[dady]

I have a little theory; much of the music we listen to in the west uses the equal temperament scale, consequently only the octave intervals of the fundamentals being played fit accurately within the harmonic series. The more complex the music, the more dissonances created by the second harmonic distortion.

The problem became with more harmonics with complex music because In the case of even harmonics If you make a chord of C with C, you will have an equivalent to C, both up and down, but in the same note, a unison. For the case of odd harmonics, if you make an A 440 with a C 1046.5 which could be your third harmonic, you will have a resulting note that can sound non-euphonically with the one the author wanted it to sound. Imagine a passage in forte of a Bruckner symphony in which monstrous chords sound at high volume; the melodies that composed the harmonies are lost if the amplifier produces many odd harmonics; likewise, the production of even harmonics is not desirable, although less so, since they will interfere with other odd notes. That is why it is better that there is almost no harmonic distortion for symphonic music and on the other hand intermodulation can be prevented by biamplifying or triamplifying.
Best Regards