SST108 // Triad 108 Spec Output Transformer


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

7 units in stock

More about the SST108:

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 1956 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 NYT? 1839 (later Triad 50264) used on the Deluxe amplifier at the cost of higher layer capacitance (wire on wire). 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.

Leads are terminated with Teflon insulated wire for abrasion resistance and longevity. I'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.

As with all of my transformers, electrical grade kraft paper is used for all layer and winding insulation. All tape used is paper based thermoset tape - just like in the old days.

SST108 Specifications:

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

Recommended for:

• 5E3 Tweed Deluxe
• Tweed Tremolux (Not 6L6 version)
• Late 50's Tweed Harvard
• 10W - 18W designs