The amp has reached the 75-hour mar. The sound seems pretty much settled by now, although many say things will keep improving.
This is my first reaction comparing the stock 1060 (original parts in) with the rebuilt 1060 in three basic comparison points:
Equipment used:
Parasound C/DC 1500 cd player
Parasound D/AC 1000 DAC
Pioneer PL-530 Turntable, Shure M97xE cartridge
Rebuilt Jenning research speakers, fr 25-24,000Hz
DIY Canare star quad cables and interconnects
I have listened to favorites tracks from the albums of Diana Krall, REM, Yo La Tengo, Pink Floyd, Kings of Convenience.
Sound signature:
-Both amps keep the same voice, as mentioned here this is related to the design.
-Music has a warm presentation, envolving and three-dimensional, the treble is smooth and never fatiguing.
Sound imaging
Stock 1060:
The sound appears to focus between the speakers.
The soundstage is credible when speaker position and room size are ideal.
Rebuilt 1060
The sound gained more horizontality and a more depth past the speakers.
Better soundstage sense and instrument realism.
A clear decaying sound of the instruments, it sustains longer without blurring into the mix.
Absolutely no background noise (hum or hiss).
Frequency response
Stock 1060:
Upper-range
Smooth sounding but a bit recessed. Typical treble instruments have definition and sound real. Tone knob needs to compensate a bit past noon 1 o'clock)
Mid-range
Female voices sound really pleasant and warm. Probably a bit bloated, I have to kick back the tone knob to tame it a bit (11 o'clock)
Lower-range,
Bass imprints a fat sense to the sound which some people like, I also had to kick back the tone knob one notch for a more balanced sound. (11 o'clock)
Rebuilt 1060:
Upper-range
Upper range instruments sound smooth and amazing realism.
Small nuances sound louder, more separations between treble instruments.
Mid-range
Mid-range is rendered very realistically without losing its warmth.
More bite, notes seem to sustain longer, clearer note decay.
The vocals definition is a quantum leap above, I can perfectly hear individual voices in a chorus.
Random recording space sounds, like a chair sliding, clapping, breathing seem to be happing in my listening room or around the house.
Lower-range
Low frequencies improved greatly, is somewhat more extended and blends well with other rages without muddying up anything.
More space around bass instruments, kick-drums, bass guitar, low piano notes, trombone all have its own place.
Less boom but more fidelity and realism, I could almots divide bass into subcategories...