The Tone Stack calculator is designed to help you check out the design and response curves of a variety of tone stacks used in popular guitar amplifiers.
It is intended to be of interest to amplifier technicians, amp modifiers, hobbyists and students. Intro The Tone Stack calculator is designed to help you check out the design and response curves of a variety of tone stacks used in popular guitar amplifiers.
Key features. Simply click on the appropriate tab to bring up a different schematic. Components : Values can be altered simply by double-clicking on the component. With potentiometers, the taper can also be altered. The generator source impedance can be altered to give realistic simulation results for both cathode followers and common cathode drivers.
Snapshots : Freeze any trace so it can be overlaid by other traces. Up to a maximum of 12 traces can be frozen in this way. Can sweep the controls to show the range.
AB763 Blackface Amp Modifications
Printing : Send the graphical results to your printer for a hard copy. Other features: Online context sensitive help, variable plot resolutions supported to optimise performance.
Operating system : Windows 95 or later. Tone Stack Calculator is a 32 bit application, and has not been tested to run under Windows 3. Processor: Minimumrecommended Pentium or better. Display : x or greater, with 16 colour capability, as a minimum. Recommended x or better. Large fonts are supported. Memory : As per minimum requirement for operating system.This is a collection of common guitar amp tone stack schematics and layouts.
I like this much more than the basic Fender Tweed Champ style single-knob tone control. Presented below are the schematic, and a layout diagram for building the tone control on a push-pull pot to include DPDT bypass. Insertion loss is relatively low at least compared to a standard 3-knob tone stack. With the tone pot placed in a local feedback loop, it should have a wide range of control.
It also came up again in a thread on low-insertion loss tone controls. Sean K. That should provide a lot of tonal possibilities with a simple circuit and low insertion loss.
In fact, the only difference really is with the treble pot. Magnatone used it in a whole series of amps — the A, MA,and BNF use it as well. Insertion loss is lower than the standard Fender tone stack, but obviously higher than 1 knob controls. Here's an in-depth analysis of it.
25 Most Valuable Amplifiers
Presented below are the schematic and 2 layout diagrams. The first is for building the stack on 2 normal pots. The second is for building it on a dual-concentric pot.
Like a tube cathode follower, the source follower lowers the driving impedance to drive the tone stack with less signal loss. I had an unused space for another switch on the front panel, so I added a tiny modification to change the frequency response of the tone stack. It simply parallels a pF capacitor with the pF treble cap.
The effect is centered around Hz, depending on the position of the controls. This is the classic 3 knob tone stack used in assorted variations in so many classic amps.
Tried and true, it has fairly high gain loss and big mid scoop. Like any tone stack, its response characteristics can be drastically altered with differing impedances and component values.If you have not been trained to work with high voltage then have an amp technician service your amp. Never touch the amplifier chassis with one hand while probing with the other hand because a lethal shock can run between your arms through your heart.
Use just one hand when working on a powered amp. See more tube amplifier safety info here. The "" in the model name comes from the circuit change date of The silverface amps are surprisingly similar to the coveted Fender blackface line of amps so many blackface mods and tweaks apply to the silverface lineup. It's pretty easy to "blackface" these amps for a full generational regression. I usually prefer switchable mods that allow me to go back to the amp's original circuit and tone.
The often unused Normal channel is also a great place to mod away with to make that channel interesting and usable. Fender made the head cab extra large to allow for distance between the power transformer and the reverb tank. Cut the NFB in half and add some color and texture.
I love this thing. Mod one of them. Click on the image to see the hi-res version. The only differences between the AA and AA Bandmaster Reverb are the AA's power transformer, bias circuit with 1k bias resistor, extra filter stage consisting of an additional 3. I changed the coupling cap to blackface standard. Note how Fender wrapped the doghouse power wires and control pot wires with red grounded wires for a "poor man's shielded cable" to reduce noise transmitted and received by these wire groups.
Differences between the AA and AA are in pink. Click the image to see the hi-res version. Download the pdf here.
The Phase Inverter Plate Load resistors are the most important blackface mod. My AA Bandmaster Reverb had a. The only other difference between the AA and AA is the AA's 1k bias resistor and extra filter stage in the bias circuit for less hum. I like to use 1 or 2 watt rated resistors on preamp plates for a little less resistor hiss.
I'm a fan of the. Fender used the smaller cap to trim some bass because the matching blackface extension cabs were closed back and had extended bass response.Log in or Sign up. The Gear Page. Jul 27, 1. Messages: I read in an old thread here that the Bandmaster style amp controls have a lot of impact on the amount of gain - if you open the bass and treble it gives you more gain and if you roll them down it lowers the amount of gain.
Anyone has experience with these amps? JohnnyBGoodeJul 27, Jul 27, 2. Messages: 2, I usually go through the 1st input but I'm liking them jumpered now. Try it! I find the amp can be a bit frustrating to dial in due to the interactiveness, but if you don't approach it like the typical Fender it can be rewarding. StringmasterJul 27, DV52H. Macdcbc and 1 other person like this. Jul 27, 3. Jul 27, 4. Messages: 19, I've owned a Clark Tyger and Victoria I think the unique tones of a tweed bandmaster-type amp has more to do with the mismatch between the OT and 3x10s.
TeleplayerJul 27, Vintage Guitar is marking 25 years of publication with a year full of features. Using data compiled for The Official Vintage Guitar Price Guidewe continue the celebration with a list of the 25 most valuable amplifiers — those that helped create the tones made famous by virtually every genre of pop music.
Heady stuff if you ever have the rare, and unlikely opportunity to strap into one. It remains one of the most emulated designs on the boutique scene, while, at the other end of the spectrum, is still a popular DIY kit for players looking to sniff a little solder for themselves.
The Bassman consolidated several major design components for the world of production guitar amps — including the long-tailed-pair phase inverter, cathode-follower tone stack, and fixed-bias output stage — many of which remain mainstays of virtually all larger amps to this day, and sounded utterly glorious in the process.
In name and initial design concept, perhaps… But a plethora of players quickly discovered that the Model was just a click around the dial from the Super Lead, and therefore a total rock monster. These ELbased class-A beauties are entirely hand-wired in the lauded point-to-point style, and deliver classic British chime, shimmer, and crunch, but with a certain modern clarity and fidelity and a bulletproof robustness relied on by countless pros.
Plug into the stout EF86 pentode preamp channel for creamy, milkshake-thick tones or the ECC83 channel for more jangle and sparkle, and you quickly hear what all the fuss is about. Turns out the Marshall PA head did much the same trick, for a little less cash — as many players quickly discovered.
This article originally appeared in VG June issue. All copyrights are by the author and Vintage Guitar magazine. Unauthorized replication or use is strictly prohibited. Current Issue Read Now!
LOG IN. Log into your account. Recover your password. Special Features. Quest for Volume. Beatle Juice. A Better Idea. Phil DeGruy. Steve Morse. Britt Daniel. Sorry, your blog cannot share posts by email.Log in or Sign up. The Gear Page. Aug 2, 1. Messages: 2, Well, I'm doin' a little buying-fixing-selling to save up 'play money' for a 5E7 build. So in the meantime I'm kicking around ideas. I'm wondering what transformer Fender used in the original, and what was its output impedance?
I gather that the 3x 8 ohm speakers are wired in parallel for about 2. So would the transformer be a 2 ohm transformer, a 4 ohm transformer, or a special-made 2. I think the one that Weber sells is a 4 ohm. Mercury Magnetics has a few different ones, including one 2. Which would you use and why?
Tweed Bandmaster/Super/Pro tone stack
Does anyone know what the transformer in the original Fender 5E7 was? Obviously the 2. Aug 2, 2. Messages: 4, They originally used a 4 ohm transformer. Part of the charm of the bandmaster was the impedance mismatch. It gets a unique tone.
Don't be tempted to upgrade the OT or you'll miss the magic. They have enough headroom and have an earlier,very musical breakup. Use the original size and impedance.
MM is fine,but Mojo makes a killer sounding one too. You don't get a better quality sounding product at any price. I do not recommend getting a 2.If you have not been trained to work with high voltage then have an amp technician service your amp. Never touch the amplifier chassis with one hand while probing with the other hand because a lethal shock can run between your arms through your heart.
Use just one hand when working on a powered amp. See more tube amplifier safety info here. The "" in the model name comes from the circuit change date of For information about the AB model differences see this. The AB circuit is considered by most to be the pinnacle of Fender amplifier design. This is why so many post-AB amps were "blackfaced" back to AB specs. I usually prefer switchable mods that keep the amp's original tone in place.
The often unused Normal channel is also a great place to mod away with to make that channel interesting and usable. If you are considering building an AB with reverb in a head cab I recommend you go no smaller on the head cab dimensions than the silver face Dual Showman Reverb head cab.
It allows for enough separation of the reverb tank and power transformer to keep hum pickup to a minimum. There's also enough room for the addition of a nice little 6" practice speaker. I love this thing. Mod one of them.
This is how. This easy mod can tune the tone. Click the image for the full size schematic. Every component function is listed. Model differences are highlighted in pink.
Click on the image to see the full size layout.