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Fractal Audio AMP models: 6G12 Concert ('60 Fender brownface Concert, 6G12)

yek

Moderator
Moderator
* EDIT: Up-to-date information is available in Yek's Guide to the Fractal Audio Amplifier Models *


6G12 Concert: based on ’60 Fender Brown Concert Amp

Another classic Fender. The brown control panel indicates it’s from the period between the Tweed and Blackface models: ’59 - ’63. Like the Tweed amps, amps from this period are very collectible. More information.

The Concert was introduced around 1960. Wikipedia states that the Concert was the same amplifier as the Fender Pro but with four 10" speakers. Premier Guitar writes that it was similar to the flag-ship Vibrasonic.

About the circuit numbers: in general the first number indicates the decennium (6 is ‘60s). The letter indicates the circuit revision, and the last number indicates the amp model (12 = Concert).​

There is a lot of variation in the appreciation of this amp. Some say it's the best thing after the "holy grail" Tweed Bassman. Some think there are better amps among the Fender Professional series from that era. It is a big and heavy beast, with its four 10" speakers. Like the Super, people love the Vibrato on this amp.

Interesting: while the Bassman was designed for bass players and adopted by guitar players, the Concert was a guitar amp which was used by living legend Carol Kaye for bass.

The version on which the model is based, has the 6G12 (not: 6G12-A) circuit with a solid-state rectifier, which puts out around 40 watts through two 6L6 tubes. It has a lot of clean headroom and a lot of bass. You have to really crank it with single coils to get it into overdrive territory, that delightful "brown" mild overdrive. (For some reason I think "brown" is a really adequate word to describe the characteristic tone of brownface amps.)

Two channels: Normal and Vibrato. The Fractal Audio model is based on the Vibrato channel, which has these controls: Bass, Treble, Volume, Presence and Vibrato (the vibrato is not modeled). There’s no Middle tone control, so keep this at “5” in the model for authenticity. No Master Volume either, so keep the Master control in the model dimed.

Note that the range of most Fender models is 1 to 10, while the model controls range from 0 to 10. Here's a handy translation table created by forum member Barhrecords.​

The Concert has two inputs per channel. Fractal Audio models of Fender amps are always based on the input with the highest input level. To get the equivalent of using the lower input, set Input Trim to 0.500.

The amp originally came with four 10” speakers (P10R, P10Q, C10R or Oxford), just like a Bassman. Use the stock UltraRes 4x10 Bassguy cab: 032. This is a great cab. Try it with any Fender model which originally came with any number of 10" speakers (like the Fender Super, discussed in the previous edition of this thread series).

A full collection of UltraRes Bassman 4x10” IRs from this amp can be purchased in Cab Pack 10, Universal Noise Storage Vol. 2: http://shop.fractalaudio.com/Cab_Pack_10_UNS_Vol_2_p/fas-801-0010.htm.​

A selection of YouTube videos:



 
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RDH

Fractal Fanatic
These amp model highlights are Great! can they all be put together in a sticky thread for quick reference?
 

TieDyedDevil

Inspired
Re: "To get the equivalent of using the lower input, set Input Trim to 0.500."

To be completely accurate, I believe you'd also need to lower the input impedance from 1M to a lower value (I don't have the manual handy; I assume there's an input impedance setting close to 136K ohms) in order to properly load passive guitar pickups. This'll further reduce the guitar's output and knock down the guitar's midrange peak a bit, which is exactly what'd happen had you plugged the guitar into the "low" input of a Fender amp.
 

greiswig

Power User
Re: "To get the equivalent of using the lower input, set Input Trim to 0.500."

To be completely accurate, I believe you'd also need to lower the input impedance from 1M to a lower value (I don't have the manual handy; I assume there's an input impedance setting close to 136K ohms) in order to properly load passive guitar pickups. This'll further reduce the guitar's output and knock down the guitar's midrange peak a bit, which is exactly what'd happen had you plugged the guitar into the "low" input of a Fender amp.
For this exact reason, I really would love to have the impedance setting moved from the front of the signal chain to the blocks themselves. It really does affect character.

I know it theoretically may be accomplished with the "auto" setting, but I've never been clear on whether it really tracks against all amp variants, especially if there are any blocks in front of the amp.
 
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