Onkyo Grand Integra M510.

Jump to Latest
#43
Hello Lubbie,
Notice this is really old thread, but if you are still around,
I Would certainly appreciate copy
odaatls-at-that-hotmail-dot-com place

I tried the link parsecaudio posted and it comes up with a bunch
of japanesse stuff in sidebar, but main page not available
"cannot find server" on bottom address bar.
 
#46
Here's some good info on the M510, including this:

"The secret inside lies in the two secondary transformers (there are six in toto) : these are "In Phase" transformers which echo the Signal In-Phase Filters of the Integra P-308 high-end preamplifier. In Phase transformers are to cope with the reactive load of loudspeakers, and not only their resistive aspect ; these transformers are to avoid the phase shift between voltage and current in the amp-to-speaker signal path.
Most pronounced around the speaker's resonance frequency, this phase-shift also happens between the voltage and the charging current in the amplifier's power supply ; these charging currents may start fluctuating along the low-frequencies contained in the musical signal. Out-of-phase charging currents can generate electromagnetic flux which in turn often induces voltages of the same incorrect phase in the nearby driver stage (through which the audio signal passes) ; the problem is then, naturally, sent to the loudspeaker... muddy bass and blurry soundstage.
Real Phase transformer are inserted between the positive and negative charging currents of the the power-supply and the capacitors : as the positive and negative currents pass through the transformer's two windings, unwanted peaks and dips cancel each other out - in phase ! You can see the schematic of the Real Phase system by clicking the "more" button below - "

http://www.thevintageknob.org/THEVAULT2/M510/M510.html#

Schematic of where the "real phase" xfmrs are inserted is shown, also.
http://www.thevintageknob.org/THEVAULT2/M510/M510-realphase.html
 
#48
This amp is overly designed. The signal path has more stages than a locomotive and the protection circuit would put a medical equipment engineer to shame. It is obvious that the designer of this amp does not subscribe to the minimalist principal. With each additional component the risk of failure goes up. I bet you this amp has one of the highest rate of failure among power amps. Don't try fixing this amp especially if the failure is in the protection circuit. I once came across an auction in eBay for one of this amp. The amp was brand new but was missing a power board. One of the amp came back for a warranty repair and the technician simply replaced the defective board with one that came from a new amp.
 
#50
caesar148 said:
This amp is overly designed. The signal path has more stages than a locomotive and the protection circuit would put a medical equipment engineer to shame. It is obvious that the designer of this amp does not subscribe to the minimalist principal. With each additional component the risk of failure goes up. I bet you this amp has one of the highest rate of failure among power amps. Don't try fixing this amp especially if the failure is in the protection circuit. I once came across an auction in eBay for one of this amp. The amp was brand new but was missing a power board. One of the amp came back for a warranty repair and the technician simply replaced the defective board with one that came from a new amp.
Click to expand...

With the older amplifier design especially the ones that uses High Speed BJTs instead of today's MOSFETs, there will be very complicated driver stages as well as the overly designed DC protection and biasing circuitry. But this amp does not have high failure rate. But there are only about 100s in the U.S and they are all over 20+ yrs old, I think it'll be fairly reasonable to assume 3-5 of them on a Tech's Bench at any given time.

I got to say, this is one of the good sounding amps that sounds closer to neutral (subjective) than most of today's MOSFETs amps. I guess mine is about time for recapping the power filters and some lytics in the input lines.
 
You must log in or register to reply here.
Top Bottom