Monday, September 13, 2010
Four Ways Street: multi-amping again...
Paying kudos to CSN&Y's masterpiece;-), after four years, I returned to active multi-amping, pals...
I felt VERY unconfortable, because I'm an extremely lazy and slow worker when having to perform major updating and modding to my system... nonethless, thanking Franz Hinterlehner's support and pushing, I took the stress of managing up-to seven amplifiers - considering some monos and some stereos - to feed the four ways of my speakers.
I truly hated the mess of cables, busy floor;-) and ground-loops buzzing due to poor, made in an hurry mains layout and multiple wall sockets use, but during the extremely tiring measuring sessions using the beauty of... pink noise, I was able to hear a definite difference from my previous use of Pioneer D-23 electronic crossover... no veiling, as I felt in the past, BUT unveiling.
Considering I'm using a cheaply, yet cleverly made, old Goto CF-1 18db/octave-3rd order active/electronic crossover with fixed frequencies cut-offs - i.e. 220/1000/5000 hz
(see here below some specs:
L channel: 220Hz or less
M channel: 220Hz - 1kHz
MH channel: 1kHz - 5kHz
H channel: 5kHz or more
Cross-over-frequency deflection Less than ±4%
Damping characteristics 18dB/oct
Passage belt gain - 1dB (M, MH, and H channel are with an output regulator)
Input impedance 50kohm
Output load impedance 300ohms or less (at the time M,MH,H channel of an output maxima)
Maximum permissible input 3Vrms
Distortion 0.15% or less (at the time of 1V input)
S/N ratio 90dB or more (each channel input 1 V:00)
Power source AC100V, 50Hz/60Hz
Power consumption About 1.5 VA)
... well, I felt someway surprised, as I was 120 percent sure my previous passive autoformers-based four-ways x-overs were doing a good job, (almost) impossible to surpass.
Today, at my (slow) pace, I re-routed all amps from same wall socket, optimized phase, and using my IVIE-IE30 and IE-20's pink noise, I made levels in about a couple of hours, including some new speakers cables making - nothing exotic, only old green Klangfilm cable;-)
... then, at last, after two days of awful-looking studio... Music, again.
Gotorama sounds like before, using passive x-over and 300B amp(s) - i.e. detailed, smooth, beautiful, pleasant... ONLY far better!
Yes, I know... everyone says multiamping is the Nirvana, BUT for me, previously using it in the past with Westrex' and RCA's drivers it was Hell-like... always fiddling with pots and listening to the same boring discs not for pleasure but for fine-tuning.
Now, be Gotorama's merits, my own improved ear and cleverness or whatever... the sense of see-through the musical event, the extremely variety of notes and tracks and recordings, the sooo dramatically improved depth and wideness of soundstage makes me both content AND a VERY beginner, a scholar, as I'll be - I'm almost sure - all my life: not a bad condition, as the sense of discovery, the surprise, the joy, yes, the childish joy of hearing and improving and learning more and more is, itself, an heavenly gift, indeed...
Well, plainly said, I feel me a lot of encouragement and support around me: people like Reinhard from Germany, Mirco from Italy, Tim from France and others let me feel like I'm not alone, but an happy (stereo) kichigai;-) - and sure, today more than ever - I feel and know "the path" is the goal, more than the goal itself.
So, multiamping again: 2 x Hiraga 20W stereo on mid-low and mid and 2 x M1 25W monos on low (missing in the pixes, shot while still fiddling) and 300B monos on high... and hearing something I'm always hungry of: more music and involvement... and Cristina Pluhar and Kings Singers never sounded this good, this evening... I unshamedly had to listen to "Les Impossibles" disk twice, as once wasn't enough!
Thanks to Franz for his support and patience and for pushing me toward the above and to Reinhard for GREAT inspiration and long-distance support and encouragement.
Thanks also to Tommy Cheung (Top Class Audio) for using his (opened) Goto CF-1 crossover pixes... so avoided opening mine: my lazyness, my fault;-)
His site is always a goldmine!
Posted by twogoodears at 9/13/2010 08:02:00 PM