MAGNATONE ESTEY M14 Twin with Stereo Pitch Vibrato

Offered for sale is this Magnatone Estey M14 amp, dating from around 1964-6.This amp is in reasonable cosmetic condition and works very well. Please examine the detailed photos below to fully assess condition and read the amp tech’s report for the full lowdown on what exactly has been done to the amp.

It has been serviced and made safe and is in good working order. All features work as they should – the pitch-shift vibrato is what Magnatones are known for and it’s easy to understand why: it makes for a unique and evocative sound – once heard, never forgotten.Please note that since the photos were taken, the amp has been fitted with a captive 3-core US 110v mains cable rather than the IEC socket shown on the photos to eliminate the risk of plugging it in to 240v.

The bass and treble tone controls are very interactive and can really shape the mids – can take some getting used to.

A great trick is to jumper the channels together and engage the vibrato: by mixing the channel levels and adjusting the tone controls you get a great phasing effect that can be almost like an autowah/filter: sonically very pleasing and quite addictive!

Magnatone amps are noted for their unique vibrato and warm break up: used by Neil Young, Dave Gilmour, Lonnie Mack, Buddy Holly, Ry Cooder and Robert Cray amongst others.

The amp tech’s report follows below:

Magnatone M14 combo

Test all valves

Fit 3-core mains cable, earth chassis to mains earth

Remove “death” capacitor x2

Replace 12-way multi-pole connector (Molex)

Tighten chassis bolts

New pilot lamp

Convert output stages to run on EL84/7189 (move screens from pin 6 to pin 9)

4x 6P14P (Soviet 7189/EL84)

1x Ecc832/12DW7 (JJ)

2x Ecc83 (used)

Notes:

The mains switch is a little unusual – it goes from “Off” to “Standby” then to “anti-hum 1” and then “anti-hum 2”. The last two are now identical i.e. “On” as I’ve removed the two death capacitors.

There was some bad arc damage on the multi-pole connector from the top chassis to the power section in the bottom. I fitted a replacement in the same hole.

Several of the valves needed replacing, but many are fine. The power valves were not good, and were 7189A’s. These are essentially an American EL84 with higher ratings. They kind of have a different pin-out, but unusually this amp has the screens wired to pin 6 so it could only use 7189A’s. I’ve moved them to pin 9 so it can now be used with EL84’s, 7189’s but you can also still use 7189A’s (if you can find any, they are pretty rare).

As the voltage on the plates/screens are pretty high, I would only put EL84’s with higher ratings in here – I’ve put Soviet 6P14P’s in it which can handle this.

It also has another unusual valve – a 7247 which is equivalent to an Ecc832 or 12DW7.

It’s an ultra-linear design, like many Magnatones, in their quest for high power and low distortion. It breaks up fairly quickly and perhaps isn’t as loud as one might expect for a 2x 12W amp; my guess is that the speakers aren’t terribly sensitive.

With a high output guitar (Les Paul etc) it gets pretty nasty, and at really high volume starts to drive the valves too hard and sounds ugly/broken.

It is a stereo amp, but doesn’t work how you might expect – both input channels go to both speakers, vibrato is on channel one only. In mono mode, you get the regular Magnatone vibrato; in stereo mode, you get lovely stereo vibrato.

Using the stereo input (a stereo jack socket) it’s just plugging into both channels at once, so as described above it’s still mono.