I guess you can ignore the BATs. They all have balanced inputs. So, you'd need to use adapters. Not sure about the others.
| Rank | Preamp | Model | Sonic Character | Strengths vs. Mapletree | Typical Used Price |
| 1 | BAT | VK-52SE | Powerful, refined, wide-bandwidth | Massive dynamics, huge stage, ultra-low noise, near-reference performance | $4,000–$5,000 |
| 2 | ModWright | LS 36.5 | Neutral-tube, dynamic | Very low noise, explosive dynamics, holographic imaging | $3,000–$4,000 |
| 3 | Aric Audio | Motherlode II/III | Big, holographic, rich | Lower noise, deeper stage, more authority while keeping tube tone | $3,000–$4,500 |
| 4 | Supratek | Chardonnay / Cortese | Huge stage, romantic | Dimensionality, bloom, scale | $2,500–$4,000 |
| 5 | BAT | VK-32SE | Neutral, fast | High bandwidth, clarity, modern BAT sound | $4,000–$5,000 |
| 6 | Pass Labs | XP-12 | Warm-neutral, powerful | Big dynamics, great bass, very quiet | $3,800–$4,800 |
| 7 | Benchmark | LA4 | Pure transparency | Lowest noise floor, absolute neutrality | $2,999 (new) |
| 8 | BAT | VK-33 | Balanced, modern | Holographic, authoritative | $3,500–$4,500 |
| 9 | BAT | VK-31SE | Warm, dimensional | Big stage, tube bloom | $2,800–$3,800 |
| 10 | Ayre | K-5xeMP | Smooth, grain-free | Very resolving, organic | $1,800–$2,500 |