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SST108 // Tweed Deluxe Output Transformer (Bobbin Wound)

The quintessential 5E3 (and more!) output transformer used by Fender in the late 1950's

Sale price$140.00 USD
Custom wound for your order! 30 days to ship.

In stock units ship within 5 business days. Custom orders will ship within the stated timeframe.

About our SST-108:

The original 108 output transformer was standard fitment on several different amplifiers in Fender's catalog during the late 1950s. This includes the Harvard (some of them), Tremolux, Vibrolux, and of course the Deluxe amps ranging from around 1957 till sometime during 1959. It's an odd design for Leo Fender to pull out of a catalog for a push-pull amplifier at the time - a decision most likely due to Triad's ability to produce them in great numbers and the low cost offered to OEM manufacturers back in the day.

What's unique in it's design is what makes it unique in it's sound. First unlike any other transformer Fender had used on their Deluxe amplifiers previously, it's wound on a plastic bobbin with a random wound primary. This technique reduces leakage inductance in the primary opening up the top end more from the earlier layer wound 1839 (later Triad 50246) used on the Deluxe amplifier at the cost of higher winding capacitance. Secondly, it's laminated with a shimmed butt stack in the core - a technique normally reserved for single-ended operation. This has the effect of reducing primary inductance at larger signal swings which in turn will reduce the low frequency content when the amp is cranked up loud. Wound for the discerning amplifier builder.

We’ve opted to terminate what would have originally been a "self lead" on the secondary common to a wire lead to prevent any chance of a floating ground occurring. Aside from this minor change, the SST108 is easily the most vintage accurate output transformer available for your 5E3 build or repair!

"The 108 sounds unbelievable in my stock deluxe! I couldn’t be happier. I’ve had 6 different output transformers in that amp, and nothing even compares to the definition and intensity of this one. Truly inspiring!"


• 8K : 8R Impedance Ratio
• Primary DCR : 650R
• Shimmed Butt Stack Core Lacing
• 15W Nominal Power Handling


• Original Style Horizontal Channel Frame Bracket
• Mounting hole centers 3 - 1/8"

Recommended for (but not limited to):

• 5E3 Tweed Deluxe
• Tweed Tremolux (Not 6L6 version)
• Tweed Vibrolux
• 10W - 18W designs