Previously So hopefully you’ve agreed that logically the two amplifiers must at all times be compared at identical SPLs? Good. Now then I'm not suggesting that you are exposed to a fixed spl throughout demo – unless you want to. Before revealing a simple strategy to bypass this all too common problem let’s consider how the system (your system perhaps with one of two amps under consideration) should perform.
First of all it should be engaging and musically credible at anything from a low volume (low spl) through the comfortable sweet spot up to what is sometimes termed as ‘realistic’ SPLs which in reality is loud or ‘bloody loud’. Notice I've used seemingly vague terms such as ‘engaging’ and ‘musically credible rather than at this stage more common terms such as bass depth, and so on.
Getting the vocabulary right
Engaging merely describes your reaction to the music played. If you find your mind wandering when its played via amplifier ‘A’ and not via ‘B’ then the answer is self-evident. If on the other hand it’s boring on both then:
- The recording process has robbed the music of its wonder through, for example, excessive compression or …
- Neither amp is up to the job and so you request that amp ‘C’ (a reference unit if you like) is introduced. If amp ‘C’ doesn’t do it then you should probably discard that recording – or get more realistic about your expectations.
So that’s it, for now, re ‘engaging’ Now then, musically credible? That’s another matter and arguably equally important. Happily the introduction of MP3 makes this far easier to explain than years ago. But first, bear in mind that for example re a piano only a truly astonishing system (mega, mega bucks) can with your eyes closed stand a chance of fooling you into thinking you are listening to that instrument played live in that room. So .. forget that _ okay?
So, using a portable device compare, even if only for a few moments, a recording of a piano in WAV or similar format and that same piece recorded on MP3. Either the difference is immediately clear to you – or you should give up hifi altogether. Obviously even the MP3 version is a recording of a piano. But switch to the WAV version and you’ll here quite a bit of what’s missing. Thus via this simple demonstration, the WAV is more musically credible than the MP3. Okay – got it?
Anyway, back in the demo room, using a cd or vinyl (I prefer a live FM broadcast myself and definitely not dab) compare the two amps at the same spl (more on this tomorrow) and usually one will sound more musically credible than the other. A warning though in that is rarely as clear cut as the MP3 versus WAV test above.
That’s it for today. Will you be joining me tomorrow? I hope so. Thank you.
Howard Popeck
