Bad Hombre tube headphone amplifier in the wild

I recently received some pics from W of a Bad Hombre Mk2 build (12AU7 + ECC99). This one uses Lundahl LL1676 input transformers and LL2765 output transformers, and features a regulated B+ and a loaded front panel of controls. Very nice!

The LL2765 is a fine transformer with ECC99 output tubes in this circuit. It has a 5k primary and multiple output taps for 32, 150, 600 ohm headphones. The 5k primary will result in more power than the 8k in the original design, but it can also be used to reflect a higher impedance depending on what taps and headphone load one chooses (e.g. 300 ohm headphones on the 150 ohm tap for 10k load).

On a side note, I see Lundahl also now has a LL2774 3k primary headphone output transformer (16, 64, 300 ohm secondary taps). This is a very similar turns ratio but it looks like the LL2774 is available with a bigger gap in single-ended configuration for higher current output tubes. Great to see new options for headphone output transformers!

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s