Onkyo Integra M-508
more affordable siblings to the Grand
Integra M-510, but bearing the same basic audio engineering
design - with a build quality a few of kilos down...
Integra P-308 sports a Subsonic
Feedback Loop between its inputs and outputs to cancel spurious DC,
ELF (no Jenna Elfman here, alas, only Extremely Low Frequency) signal
components along DC drift and intermodulation distortion - without
using coupling caps.
Cardans are set inside to keep short signal paths, and regulated,
separate, trafo windings feed each block independently : phono EQ,
linear gain, headphone. Eight inputs are available, with two dedicated
to Phono MM cartridges or Phono MC cartridges, each with two-position
trims. A contra-bass switch is added for those in need of more (light)
guts down below - but only at 200Hz.
The export models had the Line 2 inputs located front, below the
attenuator - strange move. The Tape
1 button was however (worldwide) labeled D.A.T.
- Onkyo was one year ahead. Albeit adorned with many a dispensable
function, build-quality of the P-308 is tremendously clean.
in the Grand Integra
M-510, Signal In-Phase Filters
and Charging Noise Filters iron
out differences in current and load between the P-308 and the amplifier
- the Integra M-508. Click the buttons below for the clearly explained
graphs representing these circuits.
Integra M-508 is a miniature
M-510 : same technology, same Real-Phase
circuit. However, the box dwindles from 62kg to a mere 25 (still
quite healthy !) and the overall build-quality goes with the price
- not with the 950,000¥ of the M-510. Dual-transformers, too,
but only one power cord and the eight caps amount to 80,000µF.
The two Real Phase transformers are outlined in white on the image
inside, is the Linear Switching
circuit, also used in the M-510 : high-bias and wide-bandwidth (20MHz)
power transistors to prevent crossover distortion and increase the
Class A operating range without a sliding bias system.
wood sideburns for all and Onkyo's typical (of the times) tiny flashy
LEDs indicating the P-308's state of mind : Servo Operation and
Recording Output. Bar the lamp dimmer, the M-508's functions are
identical to those of the M-510.
Both units have gold-plated terminals and a Grand
Integra badge. Said badge in the original japanese versions
was however placed elsewhere and only said... Integra