The Lead & Rhythm Professional (LR-Pro) is an original circuit design from Sanford Magnetics. This amp features a 6SL7 Octal Pre-amp tube, a 12AX7 Cathodyne Phase Inverter, 2x 6v6 Class A, Cathode Bias power section and a 5AR4 tube rectifier.
Handwired on turret boards, custom made, welded 16 gauge steel chassis, custom Heyboer transformers. The LR-Pro is a "no corners cut" amplifier.
The 6SL7 has unique way of reproducing more highs, more lows, more warmth and more chime and breaks up in such a musical way when driven. This tube just sounds bigger. While it was popular in the 50's and 60's, the 12AX7 won the race and the 6SL7 was forgotten. Using new-production 6SL7's, the LR-Pro shows how great this tube can be.
The 6v6 Class A power section of the LR-Pro puts out the perfect amount of volume for Studio and Stage. The way the amp is designed, the tubes feel like they're working from the minute you flip the stand-by switch. The tube rectifier provides the perfect amount of sag and compression.
The controls on the LR-Pro are very unique and highly interactive. They serve different applications for how the amp is being used, clean to driven.
Headroom: The headroom control, when set in the down position is perfect for dealing in a clean tone or laying back a little in a mix. In the down position, it knocks the signal down for a player that wants to use a lot of pedals. The up position ads a little push and adds hair to the notes.
Volume: The volume control is quite typical other than up to the 12 o'clock position, it sounds like most amps on 10, but with the LR-Pro, you can keep going to 20.
Thickness: Thickness control is unique. It adds thickness and lows as is it's increased, while keeping the top end relatively the same. For clean tones, this control can be used to dial in the perfect amount of jangle at lower settings or fatten the tone up for bigger cleans. When the amp is cranked, it allows you to trim the lows to dial out the low end that can make your tone boomy or muddy at high volume settings. Where you set the thickness control will vary greatly with how you set the Volume control.
Harmonics: The Harmonics control can be thought of as a fine tuning control. At lower settings, it ads presence that is gradually diminish as the control is turned up. Beyond 12 o'clock, this control ads gain.
We're quite proud of the build quality. Every part of the LR-Pro was designed with top quality as the goal, never sacrificing to cut costs. There is nothing that we'd change about the amp.
Our chassis is made of 16 Gauge steel, plasma cut, then formed on press brakes by hand. The corners are welded and the top gets a coat of paint for corrosion protection. The 14" chassis provides incredible strength and torsional rigidity. While it was difficult to design circuits into, we felt that the size and the strength of the chassis was a key consideration for the amp. Portable, but durable(indestructible), this chassis lays the groundwork for all our future amps.
The circuit board is G10 flame retardant 1/8th thick epoxyglass. Hand staked with turrets and handwired one at a time. The turret board construction leads to years of durability and is easily serviceable. Each component was carefully selected and a/b'd against everything would could get our hands on. The final selection of components represents a large amount of critical listening.
The Headshell is built with 13 Ply Void Free Baltic Birch. Wrapped in Black Levant tolex, wraparound corners and the best handle we can source.
V2-JJ 12AX7 PI
V3-V4 JJ 6V6 GT
V5-JJ 5AR4 Rectifier
15 ½" Wide
10 ½" High
8 ½" Deep