My buddy Ron Barbee has impeccable taste in vintage gear, and his Pioneer Series 20 M-22 Class A power amplifier is a case in point.
Pioneer Series 20 M-22 Class A power amplifier
Introduced in 1976, the Pioneer Series 20 M-22 Class A power amplifier is a 30 watts per channel amplifier (into 8 Ohms) with an extremely rugged build quality, and according to Pioneer "the frequency response is an amazing 2Hz to 150kHz, + 0dB/1 dB at 1 watt, and that the signal-to-noise ratio is a high 106 dB ...".
In the photo above, what appears to be the front of the amplifier is actually the back of the amplifier (as evidenced by the power cord), and the front is where all the connections are located (below).
Pioneer Series 20 M-22 Class A power amplifier
I've been listening this morning to my vintage McIntosh MX110Z - after its volume pot rebuild - with the SPEC RSA-M3 EX Real Sound Amplifier (review HERE), which is a really nice combination.
I substituted in the Pioneer Series 20 M-22 Class A power amplifier (30 watts per channel) for the SPEC RSA-M3 EX Real Sound Amplifier (60 watts per channel), and let it warm up while streaming the superb Jazz24 out of Seattle.
Vintage MX110Z pre with vintage Pioneer Series 20 M-22 Class A power amplifier powering the "Stokowski" Altec's.
Even while warming up the Pioneer Series 20 M-22 Class A power amplifier pretty much dashed any preconception of what a vintage solid-state amplifier would sound like.
Solid-state amps from the 1970's didn't have a particularly good reputation among audiophiles for sounding musically natural, and often were described as having a hard clinical balance that didn't do a good job of connecting the listener with the emotional content of the music, and having a grainy and coldly detached sound.
Well, happily that description doesn't apply to the Pioneer Series 20 M-22 Class A power amplifier at all, as it is a beautiful sounding amplifier musically and sonically, and one I could easily live with on a permanent basis.
Pioneer Series 20 M-22 Class A power amplifier
In fact, compared to superb contemporary solid-state amps like the First Watt SIT-3 or the SPEC RSA-M3 EX Real Sound Amplifier that are noted for their musical and sonic prowess, my first impressions are that the Pioneer Series 20 M-22 Class A power amplifier doesn't come up short at all.
The midrange and high's are liquid and transparent, the bass is taut and detailed, it has a natural sounding high-resolution, presents tone color beautifully, is dynamic as can be from micro to macro, with beat, rhythm, melodies, and tempos that are presented as lively and engaging, excellent imaging, and gives a beautifully satisfying sense of recorded space.
Pioneer Series 20 M-22 Class A power amplifier
The Pioneer Series 20 M-22 Class A power amplifier does that important "real sound" triad of tone, presence, and dynamics very well, which makes it sound very "alive" and engaging to listen to, and it is a terrific match to the "Stokowski" Altec's with their high-performance and state-of-art Duelund CAST tinned-copper components crossovers.
I don't know what I was expecting to hear from the Pioneer Series 20 M-22 Class A power amplifier, but it has really won me over, and I absolutely love what I'm hearing from this hifi system with this amplifier!
The Harrow & The Harvest
Switching from the Jazz24 stream to vinyl, in this case the Gillian Welch and David Rawlings album The Harrow & The Harvest, also provided some additional illumination about the Pioneer Series 20 M-22 Class A power amplifier.
The Pioneer Series 20 M-22 Class A power amplifier still had that triad of tone, presence, and dynamics in spades, making it sound very "alive" and engaging.
Resolution was impressive, unravelling Gillian's and David's harmonies even more clearly than the superb SPEC RSA-M3 EX Real Sound Amplifier, and with a lot of meaningful musical detail being evident.
Compared to the SPEC the Pioneer Series 20 M-22 Class A power amplifier is a little more vivid sounding, with a little more image presence.
Tonally I thought the Pioneer Series 20 M-22 Class A power amplifier scored very well overall, with superbly natural presentation of vocal sibilance, and with beautifully presented instrumental overtones that made Gillian's and David's guitars sound rich as well as detailed.
The vintage Pioneer Series 20 M-22 Class A power amplifier is a true blast from the past, and I really have had a blast listening to it this morning. What a nice vintage surprise for a Friday morning!
Ron is going stop by for a little listening session later today, and I'll leave the Pioneer Series 20 M-22 Class A power amplifier powered up so we can hear it in its fully warmed up state, but even with just a short warm-up period of about 20 minutes this morning while I was writing this blog post, well I'm really impressed.
I'm looking forward to getting Ron's take on how his fully warmed up vintage Pioneer Series 20 M-22 Class A power amplifier sounds in the "Stokowski" Altec system.
Pioneer Series 20 M-22 Class A power amplifier
Ok, that's all for now, and if time allows I'll provide an update on the Pioneer Series 20 M-22 Class A power amplifier a little later today.
As always, thanks for stopping by, and may the tone be with you!
