I am even a litle bit surprised that A/B amps are still being made.
[...]
It is slower than other measurements but it is automated if we settle on one THD+N % for it to use.Does the power vs. frequency measurement take a long time to make? That one addition would likely settle many questions.
You articulate the problem well. I have to think about how to best answer that with measurements....
Even if a modern integrated has 100 watts, often it doesn't have enough capacity to handle transients. My personal example are my wharfedale diamond 230 towers, i think they are 89 db/m which is not too bad, but while they are rated at 8 ohm they dip to 3.7 ohm at lower frequencies.
What he is asking for is a system answer, not a subset. He wants to know if he has speaker X, how loud can it get with amplifier under test. We would need a model for the speaker, volume of the space, seating position and amplification power.Power bandwidth. The frequency range at which the amplifier can deliver its rated power or half power bandwidth.
What he is asking for is a system answer, not a subset. He wants to know if he has speaker X, how loud can it get with amplifier under test.
Conclusions
The Musical Fidelity M2si is a well built and nice looking, branded integrated amplifier. Its preamplifier performance is very good but the power amp holds it back.
Good call. I forgot Roksan (sic!).I have a Musical Fidelity M3i and I quite like it but I have been looking around for possible replacements. I purchased mine second hand in the UK for £400 a year or so ago. I particularly like the Home Theatre pass-through. I have listened to the M2si when demo'ing my last speaker purchase, some PMC Twenty5 22's. Anyway, I really like the website, and I keen to ensure that for any future purchases I have done a bit more due diligence.
I would also echo @AudioSceptic in that, from a UK perspective, I am keen to see reviews from Arcam, Audiolab, Cambridge Audio, and Rega, I would add Rokstan to that list also.
What he is asking for is a system answer, not a subset. He wants to know if he has speaker X, how loud can it get with amplifier under test. We would need a model for the speaker, volume of the space, seating position and amplification power.
So, I basically understand why the Sony works, but I understand it after I stumbled across it, and wouldn't have known what to look for. Is it the headroom at 40hz or 45hz expressed as a percentage that would be the easiest way to quantify it relative to speaker spec?I understand that, but consider what he found with the Sony STR-V5 receiver. It sounded better (he didn't need a subwoofer and the sound was more full). Why is that so for an 85W/Ch rated amplifier from 1978?
What I can tell you about that series of Sony gear (and the integrated amplifiers TAF2650/3650/4650/5650 (VFets) from the same era circa 1977/8ish) is they had a ruler flat response of 3Hz-100KHz, truckloads of power into low impedances and a full power bandwidth from 5Hz-40or50Khz. In short, they were technically very good and beautifully designed. They are also very conservatively rated. That said, the V5 does employ current limiting in extreme situations, but my experience was it wasn't intrusive- even on the test bench.
I have a completely original TAF-3650 (same year, same series) here which when put on my bench absolutely astounded me with how good it was for a rated 55W/ch amplifier that was 40+ years old.
His STR-V5 has a massive toroidal and weighs nearly 45lbs.
I don't actually play it all that loud. It's just with the Sony i feel like I have new speakers with much expanded range and abilities (obviously they were always there i just could not access them prior). The common wisdom on less nuanced objectivist forums is that there is little difference between transparent amps that are similar in power, but that "wisdom" does not address a lot of other variables that do matter. The Sony transformed a speaker purchase that I had been regretting for two years into something I'm very happy with. I can see how someone else with a similar experience might start believing in magic because as far as they know everything they heard from their lay person objectivist friend just went out the window.What he is asking for is a system answer, not a subset. He wants to know if he has speaker X, how loud can it get with amplifier under test. We would need a model for the speaker, volume of the space, seating position and amplification power.
I'm looking for a guide to relate those figures to speaker needs especially at lower frequencies.