Marantz 8B Information

The Marantz 8B is one of those legendary tube amplifiers that reminds you why vintage American hi-fi still holds such a grip on audiophiles decades later. Beautifully recapped and restored, this example delivers that unmistakable combination of warmth, texture, and effortless musical flow that made the 8B an icon in the first place. Vocals feel rich and present, instruments carry real body and dimensionality, and there’s a sweetness to the presentation that modern gear still chases. Cosmetically, it presents wonderfully overall, with just a small nickel-sized discoloration on one transformer cover—an honest reminder that this piece has lived a life while still being ready for many more years of listening. Timeless, soulful, and increasingly difficult to find in properly restored condition.

This is the venerable Marantz 8B, from the 60’s (about mid-60’s), and a fierce competitor to the McIntosh MC240 amplifier and vintage Harman Kardon Citation amplifiers.

*Please note that we currently have two of these available for purchase and the only difference is the tube complement.  Please watch the video for full details.

We went through this amplifier thoroughly to make sure it was in tip top shape before listing it for sale.  We also made some adjustments along the way.

This is a stereo tube amplifier using a pair of EL34 pentode tubes per channel producing about 35 watts, and it’s a real 35 watts as proven on our test bench.  It’s very well built weighing in at about 56 pounds which is pretty amazing for a compact amplifier.  It originally retailed for about $275 back in the 60’s, and since the collectability is super high on these they’re quite expensive nowadays and there are not that many left.  A lot of these suffered chassis rust, and because they are heavy and hard to handle many were dropped and dented and dinged.

This is what we call a true survivor in really nice shape.

It has a set of matched EL34 tubes that are either original or period correct on the amplifier and they both say made in Holland.  Then there are GE branded 6CG7 tubes for the phase inverters and the preamp stage.

Someone might actually choose to use this amp in a monoblock configuration, in which case this has actually been modified and is the only modification you’ll find on this amplifier.  It has an internal switch which lets you parallel the outputs to get twice the power using the 16 Ohm taps.  It’s a very simple modification, just a switch with several wires tapped into the terminals.  We decided to keep this in place as there is a good likelihood that the same owner will actually want both of these that we currently have for sale, and will use them as monoblocks or dual amplifiers.

If you’re a purist and you want the switch removed, we would be happy to take care of that for you prior to leaving the shop.

Unlike most amplifiers where you just set the bias on the tubes, this one actually has an AC balance adjustment that we went through very carefully using a dummy load (per the original schematics/service notes) and a voltmeter doing some measurements along the way.  So first we did the AC balance as there’s a separate adjustment just for that piece, then we actually biased the tubes.  And it’s all working wonderfully.

On close inspection of the internals it is clear that someone has maintained this amplifier. There’s quite a bit of parts that have been replaced to be super reliable and as quiet as possible.  Some of the signal path capacitors and some of the older resistors were in fact replaced.  So this is what we consider a fully serviced unit, probably ready to operate for another 30 years.

On the back it’s pretty simple, two sets of inputs and that’s really the only unusual thing.  The second set of inputs are test inputs that are completely unfiltered, while the preamp inputs have a 20Hz rumble filter built-in to keep your speakers from getting damaged.  On the speaker side you’ll see Common, 4, 8, and 16 ohm taps, typical for this type of amplifier.  Then a slow-blow 2-1/2 amp sized fuse, and a captive power cord.  The is also a cover for a plug where there is usually a tube socket.  I believe some of these amplifiers had a tube socket to power another piece of equipment, but this one has a factory cover in its place which is pretty nice as a tube socket is pretty useless nowadays.

The paint quality is super good, I would say probably an 8/10, tiny little scuffs in the corners, but nothing really rusted.  Also has a nice golden copper (almost corrugated) finish.  The writing is complete and intact, the meter works super well, the glass is clean, the knobs are clean, overall a very presentable piece of audio history.

The other thing of note is we don’t have the tube cage for this amplifier. I understand these did sell with cages, but we’ve never come across a set of cages as they usually get crushed or rusted. It’s really pretty without it, and as long as you don’t have babies or cats running around your listening room you should be good to go.