File Size: Kb Number of Views: After downloading, the file may take a moment to open in the browser. Fender – Bassman 5f6a -Schematic Thumbnail. The Bassman 5F6-A preamp contains two voltage amplifiers, one for the bright inputs and one for the Fender Bassman 5F6-A schematic of first two stages. 5F6A Amp Kit Item Code: 5f6a_c_kt We provide a layout and a schematic (on the Technical Details tab), but we do not include step by step assembly.

Author: Meztilkree Golkree
Country: Guyana
Language: English (Spanish)
Genre: Video
Published (Last): 18 August 2009
Pages: 424
PDF File Size: 16.31 Mb
ePub File Size: 17.78 Mb
ISBN: 153-5-68293-802-9
Downloads: 94885
Price: Free* [*Free Regsitration Required]
Uploader: Zulujar

The boards are Printed Circuit Boards, and using a heat gun, I removed all the copper clad. Here is the back of the amplifier where you can see 2 of the 10″ woofers, and the tube set-up.

List of Mods

See the section above if your amp has a center tapped power supply. Many are only rated for 3 amps. For the least noise, long wire runs, or when placing the master volume pot near the power transformer shielded wire should be used. Adjust your power tube bias for max output and sweetest tone.

Be sure and get the 1N diode’s polarity right with its stripe facing the power transformer. Most of the mods below are on a switch so you can deactivate the mod.


We notice you are using an outdated version of Internet Explorer.

The signal enters the phase inverter at V3A’s grid and flows out both its plate inverted signal and cathode non-inverted signal. Like most amplifier negative feedback loops schemaric mod will reduce distortion, tighten the transition from clean to dirt and slightly reduce gain.

The larger the resistor the less negative feedback gets through to the grid. If your power transformer does have a 6. Notice how convoluted the signal flow is compared to the schematic above.

A dual gang KA pot one shaft turns both pots, audio or log taper replaces the two k power tube grid leak resistors. The power transformer puts out 7 amps of 6. Schejatic a 1MA pot with a push-pull DPDT switch and wire one leg of the master volume through the switch so when the master volume knob is down the circuit is completely disconnected. A voltage elevated Humdinger sfhematic eliminate more heater hum than any other type of heater real or artificial center tap. The switch allows you to tweak the balance between preamp and poweramp distortion.

Attenuation is only 0. The wire insulation needs to be on the wire for the turret wrap to keep the wire isolated from the turret. Tone stack’s ground wire from Shematic Tone pot terminal 1 is run to KA pot then to ground. If that happens you can put a 4. Click the image to see the PDF.


Fender Bassman 5F6-A Circuit Analysis

You must have JavaScript enabled in your browser to utilize the functionality of this website. Disconnect the bottom of the Normal channel k mixing resistor.

The Humdinger is an adjustable heater artificial ground. I was surprised by how much of a signal boost I got with this switch engaged, even with all three tone controls at max. In my 5F6A the KT88’s biased at Install an extra eyelet or turret next to the positive end of the feedback resistor for a future 3-way Negative Feedback Switch.

This grid voltage is generated by the R36 tail resistor. Lead Channel Mod I voiced the Normal channel for a tight, modern Marshall overdrive tone but left the Bright channel unmodified. Reduce ‘ice pick’ Highs: Guitar Amplifier Preamps2nd Edition. This prevents a current surge when you close the Standby Switch.

The wire from the 1 left pot terminal would be wired as normal to the left k resistor see layout below.