Jerry Garcia’s McIntosh amp

I'd have to say the the 1976 - 1978 years were a great run for the band. That's when I started following them. The Ithaca show at Cornell in 1977 was one of those talked about for years shows. I was pretty young then and a cadre among the much older Dead Heads touring used to always opine to me about the good old days when Pigpen with the band.

Many thanks for all the insights offered here. The music never stopped.

https://www.youtube.com/watch?v=r86Sb4heCWM As can be seen in the video Phase Linear amps were used in the Wall Of Sound. These are what i remember as i mentioned earlier.

chorus, Curl could have been there but you have to remember that there was at least 50 people that worked to put that sound system together and the only people at that time  were the Dead that everyone knew, no one but them at that time had a reputation and everyone else were just faces. 

I built and designed speakers and lent my ear in the recording studio.

The amp was correctly called in post #2 - an MC2300.  McIntosh amps comprised the Wall of Sound, not Phase Linear.  (48) MC2300 and a handful of MC-3500s were used.  Numerous drawings, photos, threads, and videos (including the one referenced just above), and even the Grateful Dead movie show the amps.  McIntosh even developed a bit of a marketing campaign around the fact that both Woodstock and the Grateful Dead chose McIntosh amplification and an even opened a Gradeful Dead exhibit at the R&R HOF - https://www.mcintoshlabs.com/brand/news/Grateful-Dead-Exhibit-at-Rock-and-Roll-Hall-of-Fame

Reportedly, Jerry played through one channel of the MC2300 only while on stage.  The particular MC2300 he was seen most often with has a sticker on it of a guy playing the guitar.  This was known as the Bud Man amp.  Just google "bud man mc2300" for many pictures of Jerry's setup.

Also reportedly, the MC2300(s) that Jerry played through were modified.  Some claim that Alembic removed the McIntosh sentry monitor circuit entirely.  Others claim that not to be true.  Rear panels had banana jacks added to them to facilitate quicker connections to the speakers.

At some point, after McIntosh introduced the MC2500 in 1980, Jerry did try one of these.  There are a handful of photos of him playing on stage with an MC2500 and not the Bud Man MC2300.  This didn't last long however.  Try as I may, I've been unable to determine why.

I met Bear in the 1990s, after running an ad on the Grateful Dead's website looking to purchase the McIntosh amps used in the WOS.  What an eclectic personality.  I sure wish I would have had the foresight to archive that convo . . . 

I have a bunch of these amps . . . 2300s, 2500s, and 2600s even.  The hype is real.   Have fun.