This is a vintage 1967 Sound City Studio 20 amplifier head by Dallas Arbiter. This incredible sounding small tube amp was manufactured by Elpico, as the model AC88 amplifier, as inscribed upon the circuit board within this very amp. This very nice example is in quite crisp cosmetic condition, and retains an entirely original set Mullard and other vintage tubes; (1) EZ81, (2) EL84s, and (3) ECC83s, and yep, that is the exact tube line-up found within the famous Marshall 18-watt (1974) Mini-Bluesbreaker. The amp has been serviced by Mike Franceschini from 65Amp, including being set up for 110v and installing a new power cable, and sounds absolutely amazing. When paired with a single 12″ speaker, this thing is undeniably unbeatable. If price were determined by sound and tone, these would sell for $10,000.00.