Amp/Preamp Asylum: REVIEW: Pioneer SM-83 Integrated Amplifier (Tube) by LinuxGuru

Model:	SM-83
Category:	Integrated Amplifier (Tube)
Suggested Retail Price:	$250-300
Description:	Pioneer SM-83 Vacuum Tube Integrated Amplifier (1969)
Manufacturer URL:	Pioneer
Model Picture:	View

Review by LinuxGuru on March 21, 2009 at 07:07:19
IP Address: 83.99.214.85 Add Your Review
for the SM-83

Pioneer SM-83 is a typical vacuum tube integrated amplifier of the 60th era - very solid and heavy steel chassis, 5mm thick aluminum brushed faceplate, 12AX7 pre-amplifier, 6AN8 mediim-mu triode/sharp cut-off penthode inverter, class AB push-pull 7189a output stage with 460V plate voltage (claimed RMS was 28W per channel driving 7189a to the utmost edge), and a couple of nice Tamura (Tamradio) output transformers (Tamura still in the business today as one of the largest Japanese transformer manufacturers). Construction is very smart, there are no rivets, no parts soldered straight to chassis except few grounding cables, so amplifier could be very easily disassembled apart. Quality and layout of assembly is very logical and accurate.

I will skip restoration process overview because its too long and is off topic here, but you can find it following link below:

http://www.starlett.com/~web5_macguru/audio_pioneer_sm83_restoration_en.html

I listened many melodies of different styles: "Gladiator Symphonic Suite" - "The City of Prague Philharmonic Orchestra" (absolutely astonishing and awesome!), "Final Fantasy Symphonic Suite" - "Nabuo Uematsu", "Rent" - "Pet Shop Boys", "I Don't Like Mondays" - "Boomtown Rats", "Chanson Simple" - "Patricia Kaas" - and many others. All listed above sounded fantastic. Very clear and detailed reproduction, deep soundstage. Metal rocks from Gladiator Symphonic melody absolutely realistic. Piano accords from "I Don't Like Mondays" were something I have not heard before. Vocals (Patricia Kaas, Sarah Brightman) matches Sansui in all aspects. However, "Alizee", "ABBA", "Al Bano & Romina Power", "Roxette"- very good, but not breathtaking. I do not know why, probably its just my personal taste and impression. What other people say? One of my friends listened my setup with this Pioneer SM-83 called it "true live sound" system. Need to say, I use top-notch 4-way high-sensitive speaker systems (Technics SB-G710 and Sansui SP-Z99), with very large woofers, 36 and 43.6 sm respectively. These are very few (unlike plastic-cardboard junk manufactured today in sheer numbers) which can create in average living room what we call holographic soundstage (literally translated from Russian).

How it compares to Sansui G4700 (which I consider a crown jewel of transistor art of audio engineering) and another tube amp Fisher 400 I restored before? In terms of sound quality, they all are excellent performers very close to each other. IMHO there is no absolute and clear winner, and that's I consider great. In race for music realism its a listener who should be benefited most! Anyway, Sansui G Pure DC is still not decrowned as true Hi-Fi sound king, at least for me. All tube amplifiers I listened (including 3 units I owned personally) can match it in certain aspects, but they still cannot outperform and outclass it in all areas even by a narrow margin.

Product Weakness:	40+year old carbon resistors and potentiometers completely out of tolerance, replacement 2-gang long-shaft pots are very to find. Very dense point-to pint circuit.
Product Strengths:	Excellent performer. Quality and layout of assembly is very logical and accurate.

Associated Equipment for this Review:

Amplifier: SM-83
Preamplifier (or None if Integrated): SM-83
Sources (CDP/Turntable): PC with SoundBlaster, FLAC lossless
Speakers: 4-way Technics G710 (98 dB/W/m), Sansui SP-Z99 (100 dB/W/m)
Cables/Interconnects: General Purpose, Not a Cable Freak
Music Used (Genre/Selections): Instrumental, Rock, Vocals
Room Comments/Treatments: Standard 20m^2
Time Period/Length of Audition: Over 1 months
Type of Audition/Review: Product Owner

Amplifier:	SM-83
Preamplifier (or None if Integrated):	SM-83
Sources (CDP/Turntable):	PC with SoundBlaster, FLAC lossless
Speakers:	4-way Technics G710 (98 dB/W/m), Sansui SP-Z99 (100 dB/W/m)
Cables/Interconnects:	General Purpose, Not a Cable Freak
Music Used (Genre/Selections):	Instrumental, Rock, Vocals
Room Comments/Treatments:	Standard 20m^2
Time Period/Length of Audition:	Over 1 months
Type of Audition/Review:	Product Owner