As promised, some pics. Haven't had time to compare with the EB circuit, but it certainly didn't knock my socks off with the stock capsule. That said, at a glance and being a novice, the circuit looks better than I expected.
I'm thinking about going dumb with it and dropping in my CT-12 to see how that sounds. I realize it's ridiculous to put in a capsule that's worth twice what the mic cost, and I'll probably pull it once I get my PTP 251 built, but why not give it a spin.
Without further ado:
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Updated with observations: (my novice observations aided by ChatGPT)
EB Comb (Original Version)
- Amplification stage transistors:
- T2: 2SK30A-R (JFET)
- T3: BC413C (BJT)
- DC converter transistors:
- Output transformer:
- 1.33:1 ratio (low step-down, maintaining higher output level and providing a vintage, full-bodied tone)
EB P48 (Phantom-Powered Version)
- Amplification stage transistors:
- T2: 2SK30A-R (JFET)
- T3: BC413C (BJT)
- DC converter transistors:
- Output transformer:
- 6:1 ratio (high step-down, reducing output and impedance for compatibility with modern preamps)
WA-14
- Amplification stage transistors:
- Q4: 2SK118 (modern JFET with improved noise performance)
- Q3: BC550C (modern low-noise, high-gain BJT)
- DC converter transistors:
- Q1: BC550C (modern low-noise BJT)
- Q2: Likely 2N6510 (high-voltage NPN transistor)
- Output transformer:
- 3:1 ratio (mid-range step-down, providing a balance between vintage warmth and modern performance with increased headroom)