Ampex Tape Machines
Summary
Abstract
Ampex tape machines and their preamp electronics are legendary in the recording world. The Ampex 350/351 preamp — the tube electronics pulled from old Ampex tape machines — is considered by community members to be the ultimate tube preamp, with cian riordan calling it “the only tube preamp you’ll ever need.” The Soundtoys Decapitator’s default ‘A’ setting is modeled after it. These are finite vintage pieces that will never be made again.
Key Characteristics
- Ampex 350/351 preamp: Tube electronics from vintage tape machines; does clean, dirty, and everything in between
- “BIG sound” — not the subtle, boring clarity of modern tube preamps
- Can run line-level signals through it for thickening or full distortion — “so goddamn musically all the time”
- No phantom power (pre-dates the concept) — requires external +48V supply or modification
- Maintenance comparable to or easier than modern tube preamps due to widely available tubes and documentation
- Prices around $2,200 on the used market; likely to appreciate in value
- The Soundtoys Decapitator default ‘A’ model is based on the Ampex 351
Use Cases
- Vocal recording — “literally never found a situation when this mic pre doesn’t work”
- Line-level signal processing for saturation and color
- Deliberate distortion for creative effect
- Universal preamp for any source material
- Investment piece — “if you buy one now, chances are it’ll be worth double in 5 years”
Settings & Sweet Spots
- Works at all gain levels from clean to fully distorted
- Line-level input for re-amping and saturation of already-recorded material
- External +48V phantom power supply ($25 on Amazon) needed for condenser mics
- Electric and Company versions are potentially worthy modern alternatives to vintage units
Comparable Alternatives
| Gear | Notes |
|---|---|
| Soundtoys Decapitator | Plugin modeled after the 351; default ‘A’ setting |
| Scully 280 | Another vintage tape machine preamp; different character |
| Thermionic Culture Vulture | Hardware saturation with a “very different flavor” |
| Summit Audio TPA-200B | Modern tube pre; clean but lacks the Ampex “BIG sound” |
| Tube-Tech / DW Fearn | ”Boring” modern tube pres compared to Ampex character |
| Old Tascam mixers | Budget alternative for gritty saturation |
Common Mistakes
- Spending money on “boring” modern tube preamps when the Ampex offers vastly more character
- Not budgeting for an external phantom power supply
- Overlooking that quality interface preamps may be sufficient before investing in outboard
- Forgetting to factor in installation/repair costs with any vintage gear purchase
See Also
Source Discussions
Community Insights
“The Ampex 350/351 is the only tube preamp you’ll ever need.” — cian riordan
“Modern tube-mic-pre design can be so boring with the emphasis on clarity and subtle warmth. Summit? Yea fine. Tube-tech? Sure. DW Fearn? Boring. When you go with something like the Ampex, you’re tapping into a BIG sound.” — cian riordan
“The Decapitator default ‘A’ setting that everyone uses is modeled after it.” — cian riordan
“Stuff like the Ampex 351, Scully 280, or even cheaper gear like old Tascam mixers has worked better for me many times.” — sinaigimenez