dating a Silverface Vibrolux Reverb?
FENDER AMP Chassis Serial Number DATE CODES .. Vibrolux Reverb AA , AA, AB, AA (silverface) A to A - A to. The 35w blackface Vibrolux Reverb (VR) is the smallest member of the blackface/ silverface 6L6 Fender amp family. Its strength lies in the sweetness and early. A friend dropped his Silverface Vibrolux Reverb off at my place so that Dave's Silerface Vibrolux Reverb: to known date of your fender amp.
We often find the reverb sweet spot around 2. Some amps are sensitive and difficult to control the reverb on. The whole dynamic area can be within a narrow interval, i. These amps require a careful touch when dialling in the reverb, which irritates us.
- dating a Silverface Vibrolux Reverb?
- May the tone be with you
The reverb circuitry consists of two tube sections reverb driver V3 and reverb recovery V4 and the physical reverb tank. If you replace the V3 12AT7 reverb driver with a 12AU7, you will reduce the effect of the reverb and it will be much easier to control with the reverb knob. So simple as that.
Use normal channel for reverb control — Adjust EQ and depth of reverb. This mod is relevant only for two-channel amps with normal and vibrato channel.
Vibrolux Experts: Date this silverface for me
Plug your guitar into the vibrato channel, then unplug the reverb return cable on the back of the amp the one that comes from the reverb tank output and plug it into the normal channel input. The reverb knob on the vibrato channel will have no effect any longer. This mod is not applicable together with the Pull V1 mod, as you need the normal channel preamp tube. Diode rectifier — More clean headroom. A good thing with this mod is that you have both the tremolo pedal and spst pot to use.
This mod can be implemented in two ways, either by unsoldering the tremolo circuit or replacing the tremolo intensity pot with a swicthable pot, so-called SPST pot. The switch is enabled when you turn down intensity to zero. Order a 50k SPST from one of our recommended amp part dealers. The black plastic wheel is to be used for the new pot. See the wiring diagram below. Then solder a new red wire between the other side of switch to the right lug. Note that the figure below shows the Super Reverb.
You will not need to replace the intensity pot with a spst, but let the yellow wire to the tremolo pot go through the tremolo pedal. In our opinion this is not a good idea since one loses the possibility to use both the spst switch and tremolo pedal. Using the pedal will now involve a significant click sound and volume increase. You can select which one that matches your tone and style. Bias electrolytic cap was changed from 25? Voltage divider resistor in filter cap circuitry was changed from 10KOhm to 4.
The red circles indicate the changes in figures below. Click images for full size versions. Negative feedback loop The negative feedback loop can easily be tweaked to alter the treble cut and distortion in your amp. The NBF theory is that you take the signal from the speaker output, let it go through a resistor and mix it in at the entry point of the phase inverter. The speaker signal is out of phase degrees with the signal at the entry point of the phase inverter and will cancel out equal frequencies.
Most importantly the tone gets rougher and rawer with more mids and higher frequencies, aka presence. You may choose to implement the mod in several ways and in various combinations with the ground switch or a foot pedal. No negative feedback at all. Simply disconnect the feedback loop a wire and tape insulate it. You get the most effect of this mod by disconnecting the NFB loop entirely. If so, read more about the cap in the next bullet point.
BF/SF Vibrolux Reverb | n3ws.info
Keep the feedback loop and install a. Depending on the cap value treble frequencies will be fed back to the phase inverter which cancels out the treble in the main path. The tone gets less harsh and you still have a noticeable effect. Probably the same as the pots and transformers that we just dug out of the boxes.
I think in the corners of the boxes were older pots remaining from earlier dates I think the better, older hands did 35 a day. Like I said, there were 5 or 6 of us at the benches every day. But it wasn't always 'cool guitar' amps, sometimes I was making Fender Rhodes Satellite amps on bent aluminum, sometimes only Champs.
I remember two 'suits' from upstairs standing behind me occasionally doing time studies. They actually held clipboards and stopwatches to measure how long it took for me to attach various parts. Of course I tended to hurry more when they were there, and I would fumble more, too. Same with the little rectifier boards. When we had filled our cart we'd wheel it over to the Chicano chicks. They were something to behold, all chatting away while soldering so quickly, it didn't hardly seem like they were looking at the amps.
After that the foreman would add the tubes, turn 'em on and set the bias. One has to wonder where all those factory original export back panels are!
Another interesting tidbit is that a lot of Fenders were imported into Australia in the late s and early s that were stock volt domestic US units. The Australian Fender Distributor then installed V - V stepdown transformers in the bottom of the cabinets.
Note the removal of the voltage selector switch and hard-wiring. Also note the vertical black lines on the control panel found on earliest silverface amps and the large ceramic power resistors coming off the power tube sockets which indicates the AB circuit. I just discovered that the silverface Bandmaster speaker cabinet the big, tall one without tilt-back legs is ported see photo.
How to date vintage fender amps
I thought they were completely sealed units. One thing we know for sure is that production codes can help date an amp to a particular month within a given model run. Greg and I also disagree about determining production from serial numbers. I will present my hypothesis here and let Greg present his side of the story in a future article.
Unlike serial numbers used for most Fender guitars and basses, we know that serial number sequences are unique to a particular model or a family of models of amplifiers.
Because the serial numbers are for a particular model and that chassis were stamped sequentially, is reasonable to assume that the serial number infers the Nth unit manufactured. Some caution is advised since it is likely that not all chassis were used due to defects or that duplicate serial numbers may have been stamped. There is no way to separate out production for these models, but with enough data, we might be able to do some frequency distribution and such to determine a rough estimate.