The Brownface Amps
There are not many of these amps around. They were an evolutionary step from the Tweed amp versions and the long lived Blackface/Silverface years. From the early 60's up to about 1963.
Sound wise I have not heard that many in person. A Brownface Deluxe and a Brownface Vibroverb are all I have been able to listen to in person. There are more clips on the Net but so much depends on the quality of the recording and the speakers you listen to on your PC its hard to get the same impression as in person.
I think they are like a tweed/blackface hybrid sound. More dark sounding than the later Blackface amps but more sparkly that the Tweeds.
Among several of the circuits I have built, my favorites are the Deluxe which has a Tremolo circuit but no reverb and the Vibroverb. The Vibroverb is the first Fender to feature reverb. Its also has tremolo based on the bias modulation technique. This means it actually varies the bias voltage to the power tubes to get tremolo (or vibrato as Fender called it) rather than the later Blackface amps that use a device called an optoisolator- or cricket. Its actually got a sealed light source that varies its strength based on the voltage supplied and a receiving device that passes that voltage- or pulse- on to the output circuit. Its more of an on/off device rather than the Brownface bias modulation technique. The Brownface circuit produces a softer and more organic pulse. Frankly, its harder to get the Bias Modulation working right and tube bias is critical to it sounding right. Fender had many issues since most folks let their amps get out of bias spec and the tremolo would then go away or sound very faint. Surprisingly, the Blackface Princeton Reverb has a version of this bias modulation tremolo and its the only one in the Blackface years to keep it.
Here are some pictures of my Brownface Vibroverb builds. Using 2 6l6 power tubes for close to 40 watts of power, it has tremolo on both channels but reverb only on the second reverb channel. I could modify it to have reverb on both but I goosed up the normal channel gain a little instead for some nice breakup. It uses 2 10" speakers which by 1964 had been replaced in the Blackface version with one 15" speaker. Stevie Ray made the Blackface version famous as he used it a lot. The Brownface Vibroverb is probably one of the rarest of all Fender amps. It was made only for 1 year I believe. Great cleans, deep reverb and a soft organic tremolo. Overdrives nicely as well.
There is a lot going on in these amp circuits. From the Brownface and Blonde amps of the early 60's, the rest of the Blackface and Silverface build techniques were set into place. There are many parts, a lot of wiring paths and a builder needs to be sure to adhere to the correct layout or chances of noisy and unpleasant sounding amps increases greatly. I like to use solid core cloth covered wire for these replica style builds. It stays put and allows me to keep things under control. Yes, it costs more but sounds better in the end.
This is the backside of the Vibroverb. Dual 10" speakers. Very rare to find an original one.
Below is a Vibroverb head I built. Never made originally, a head option if great if you want to be able to match your amp with different speaker cabs. Saves money as well.
Sound wise I have not heard that many in person. A Brownface Deluxe and a Brownface Vibroverb are all I have been able to listen to in person. There are more clips on the Net but so much depends on the quality of the recording and the speakers you listen to on your PC its hard to get the same impression as in person.
I think they are like a tweed/blackface hybrid sound. More dark sounding than the later Blackface amps but more sparkly that the Tweeds.
Among several of the circuits I have built, my favorites are the Deluxe which has a Tremolo circuit but no reverb and the Vibroverb. The Vibroverb is the first Fender to feature reverb. Its also has tremolo based on the bias modulation technique. This means it actually varies the bias voltage to the power tubes to get tremolo (or vibrato as Fender called it) rather than the later Blackface amps that use a device called an optoisolator- or cricket. Its actually got a sealed light source that varies its strength based on the voltage supplied and a receiving device that passes that voltage- or pulse- on to the output circuit. Its more of an on/off device rather than the Brownface bias modulation technique. The Brownface circuit produces a softer and more organic pulse. Frankly, its harder to get the Bias Modulation working right and tube bias is critical to it sounding right. Fender had many issues since most folks let their amps get out of bias spec and the tremolo would then go away or sound very faint. Surprisingly, the Blackface Princeton Reverb has a version of this bias modulation tremolo and its the only one in the Blackface years to keep it.
Here are some pictures of my Brownface Vibroverb builds. Using 2 6l6 power tubes for close to 40 watts of power, it has tremolo on both channels but reverb only on the second reverb channel. I could modify it to have reverb on both but I goosed up the normal channel gain a little instead for some nice breakup. It uses 2 10" speakers which by 1964 had been replaced in the Blackface version with one 15" speaker. Stevie Ray made the Blackface version famous as he used it a lot. The Brownface Vibroverb is probably one of the rarest of all Fender amps. It was made only for 1 year I believe. Great cleans, deep reverb and a soft organic tremolo. Overdrives nicely as well.
There is a lot going on in these amp circuits. From the Brownface and Blonde amps of the early 60's, the rest of the Blackface and Silverface build techniques were set into place. There are many parts, a lot of wiring paths and a builder needs to be sure to adhere to the correct layout or chances of noisy and unpleasant sounding amps increases greatly. I like to use solid core cloth covered wire for these replica style builds. It stays put and allows me to keep things under control. Yes, it costs more but sounds better in the end.
This is the backside of the Vibroverb. Dual 10" speakers. Very rare to find an original one.
Below is a Vibroverb head I built. Never made originally, a head option if great if you want to be able to match your amp with different speaker cabs. Saves money as well.