The history of the Music Man company began about 1971 when Tom Walker, Forrest White and Leo Fender started a company called Tri-Sonic. Walker and White had worked for Fender before. Leo Fender himself had to sign a 10 years non-compete contract when he sold his company Fender Musical Instruments to the CBS Corporation in 1965, so he remained in the background until 1975.
In 1974 the company name was changed to Music Man, and in 1975 Leo Fender was named as its president.
Music Man started their amp line in 1974. It is not absolutely clear in how far Leo Fender was involved with the design of these amps, most sources say that alone Tom Walker was responsible for the amps, while Leo Fender designed the guitars and bass guitars.
The first Music Man amp – a head called Sixty-five – had already most features of all later models. In very short, these are:
- A hybrid design with a tube output section and a solid-state pre-amp section
- Overall look and control layout similar to Fender amps
The hybrid design – Get that Fender sound with a solid-state design
Fender amps were basically built for a clean sound. The distortion that is created when a tube amp is overdriven was something invented by creative musicians or by chance when musicians tried to get as much volume out of their amps as possible. Fender didn`t focus on the distorted sound, in the contrary, they even tried to avoid it. In the mid-seventies , the famous Fender Twin Reverb even made use of some tricks often found in HIFI amps to reduce as much distortion as possible (the so-called ultra-linear circuit).
It is surely fair to say that Music Man followed the footsteps of earlier Fender amps, so their amps were also aimed at the best possible clean sound. So it is not a big surprise that they used a solid-state design (ICs and transistors) for the pre-amp section. Solid -state requires lower voltage and less energy and thus causes less heat. For this reason it was considered as more reliable than tubes.
The whole pre-amp section is mounted on a printed circuit board, while Fender amps still used point-to-point wiring for their amps at this time.
Tube power for warmth
The output section of the first Music Man amps used 6CA7 power tubes. A tube output section adds a certain warmth and subtle distortion to the clean sound. This is the opposite approach to the more modern approach of using a tube pre-amp with a heavy-duty solid-state power amp, a setup more suited for that singing, high-gain distortion.
The 6CA7 tube is pin-compatible with the EL34, the tube that was made famous by Marshall amps, while Fender amps mostly used 6L6 tubes (or 6V6 for smaller amps). The 6CA7 can simply be replaced with EL34. As today hardly any tube manufacturer still produces the 6CA7, most Music Man amps meanwhile run on EL34s.
However, the circuit was rather different from Marshall. The power tubes in a Music Man amp operate at up to 700 volts at the plate. Fender or other tube amps – including Marshalls – normally have about 450 – 550 volts here.
About 1980 Music Man changed from 6CA7 to 6L6 tubes. Apparently this had not to do with tonal preference but with supply facilities at that time. Generally the amps kept their typical Music Man sound, no matter whether they had 6CA7/EL34 or 6L6.
The rectifier was solid-state (diodes) and not a tube rectifier like in many early Fender amps. A tube rectifier causes a drop in voltage during the moment the amp is driven to maximum output. Thus, the sound becomes softer, similar to a compressor. Solid-state rectifiers sounds punchier and slightly harder.
Originally there was one pre-amp tube – a 12AX7 – used for the phase inverter stage of the amp. This is the stage between pre-amp and power amp. This way a certain amount of tube distortion was added. In about 1977 this tube was replaced with a solid-state version. The reason was that a certain malfunction of this tube could cause severe damage to the complete output section, including a damage to the power tubes and the expensive output transformer. The amps with the new solid-state phase inverter still sound very similar to the earlier models, but are nevertheless by some considered as sounding not as warm as before.
All Music Man amps can be switched to low power. This is not realized by switching off some of the power tubes like some other manuyfacturers do, but with a reduction of the voltages at which the power tubes run.
Music Man amps look very much like a typical Fender combo amp from the 60ies or 70ies. Like those black-face Fenders, they have a black control plate, a silver grill cloth to protect the speakers, and are covered with black tolex. The handle and the casters on some models are also very similar to Fender. Unlike Fenders, the Music Man amps never had those tilt-back legs that allow to tilt back the amp to adjust the speaker on the player`s ears instead on his knees.
All early Music Man amp models were 2-channel amps. The reverb and the tremolo effect affects the second channel only.
The reverb was based on a Acutronics reverb spring, similar to the one in Fender amps. However, the reverb sound is different – thinner and brighter – than the extremely warm Fender reverb. This is rather due to the circuit design than to the spring itself. The tremolo effect is very effective, but also sounds different than on Fender amps.
The Music Man logos came in two versions: the original one was black on silver, while after 1980 it was silver on black. This way you can tell the older amps from later ones at first glance.
Most early Music Man amps had speaker made by Eminence, typically models with square alnico magnets. About 1980 they changed to round ceramic magnets, still produced by Eminence. However, some models with 10″ speakers always had ceramic magnets.
Other important players of that time who used Music Man were Eric Clapton, Johnny Winter or Albert Lee.
More information on Music Man amps can be found here. One of the next articles will cover the Mark Knopfler model, the 212 HD 130.