Sound Pure's Take
Condition: Used, Very Good
From Other (Miscellanous Used/Vintage/Consign)
The Girthmaster guitar amp circuit was developed back in 2013 with several design objectives. I wanted to create a wide gain structure with a short signal path, which means using only a couple of gain stages before the phase inverter. Less gain stages translates into more dynamic range, that allows you to crank up the amp and have a full range of clean tones available by controlling pick attack and your volume control on the guitar.
It was important to be able to pour this circuit into a wide variety of great old public address amps, that often support only a few preamp tubes and have only a limited number of controls to work with. The circuit also had to be very flexible so it could be used with a wide variety of odd and old style tubes.
The Girth control is a key part of what makes this design work so well. Right after the first preamp stage, is the typical volume control that we label as gain. The girth control is another volume like control located after the 2nd preamp stage. By having these two controls, you can set the amp up over a much wider range.
At first, most were built into models that are commonly referred to as lunch-box sized amps, because of their small compact size. The small amps I refer to would typically have a pair of 6V6 or EL84 power tubesm making from 10 to 20 watts depending on the transformers and power supply.
With some minor modifications I adapted the girthmaster idea to fit into larger amps that might have a pair, or two pairs of 6L6 tubes, to produce from 30 to 80 watts of power.
Modified MASCO MA35
- Year
- 2015
- Power Supply
- Solid State
- Preamp Tubes
- 12AX7, 7F7
- Vibrato
- 7F7
- Phase Inverter
- 12AX7
- Power Tubes
- Dual 6L6GC
- Front Panel
- Input Jack, Girth, Bass, Middle with Pull Boost Switch, Treble, Master Volume, A-A/B Power Tube Bias Switch, Power Switch with Middle Standby
- Wattage
- A Switch - 22 Watts, AB Switch - 30 Watts
- Back Panel
- Dual Speaker Jacks, 4-8-16 ohm load terminals, cabinet voiced D/I jack, Gibson Style Vibrato with Depth and Frequency controls, remote jacks for mid boost and effects control
Warranty
This item is sold without the Sound Pure 3-year warranty (used / B-stock / dealer-exempt). Coverage terms for items in this category live in Terms & Conditions, Section 27.
Returns
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