- 2 x 25 W @ 8 Ohms in Class-A (1,25A bias current)
- 4 transformer-coupled inputs (2 balanced, 2 single-ended), relay-switched
- 2-stage tube voltage amplification using 2 half ECC82 per channel in a Loftin-White configuration
- ECC82s are under-heated to enhance long-term stability of characteristics
- Lundahl input and interstage transformers
- No capacitor in the direct signal path
- Zero dB feedback
- 2-stage current amplification using Mosfets drivers and bipolar power transistors
- High-voltage valve rectifier EZ80 and extensive PI-filtering
- High-capacity power supply with PI-filtering
This amplifier is used best with speakers like Lowther, if you stay with this type of speaker you will be rewarded with the combination of the best characteristics of a single ended tube amplifier and a Class-A transistor amplifier. I must admit that the results with my JBL 4430 monitors were not equally satisfying as the output impedance has the same magnitude as a single ended no-feedback 300B amplifier.
BTW, Guido Tent published an article in the June 1999 issue of “Audio en Tecnhiek” which features similar design objectives and solutions.
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