New · Version 3
APX-351
The tube front end of a legendary American tape recorder, rebuilt. Neural models running at their native 192 kHz, a low-CPU mode for big sessions, Bass Cut and a true VU, behind a brand-new faceplate.
Free update for APX-351 owners · Full-version trial for 15 days · Online activation
See it in action
Walkthrough & demos
Overview & walkthrough
In action
Vintage American iron
A Class-A gain stage, transformer-coupled in and out — the holy grail front end that warmed a generation of recordings.
APX-351 captures that amplifier with neural models trained on the original hardware, so the triode saturation, the transformer weight and the way it gives as you push all come from the real unit.
Soft mode is gentle, musical warmth for vocals and acoustic sources. Hard mode pushes into driven territory — serious punch for drums and bass.
Hear the difference
Before and after, on real material
Hear it in action across a variety of sources.
What's new in V3
Rebuilt from the tubes up.
Same two captures, Soft and Hard. Everything around them is new.
Native 192 kHz neural engine
The Ultra models were captured at 176.4/192 kHz, so V3 runs them there: 4× at 44.1/48 k, 2× at 88.2/96 k, straight through at 192 k. No false top-end, no aliasing, even pushed hard.
Low-CPU mode for big sessions
Switch HQ MODE off and the 44.1 kHz models run at your session rate: about a third of the CPU, level-matched, with the same latency, so you can put one on every track. Mode changes crossfade and never click. The engine picks its maths for your processor: NEON on Apple Silicon, AVX2 on modern Intel and AMD.
Bass Cut
Keep the lows clean while the tubes work on everything else. A 120 Hz crossover sends only the mids and highs through the saturation; the low end rejoins at the model's own level, so the balance stays put as you drive it.
A VU that tells the truth
Real VU ballistics, sample by sample: 300 ms rise, 0 VU at −14 dBFS, a needle that rests at −20 behind a lamp-lit dial. Plus AUTO gain matching, A/B, undo/redo, HPF/LPF, Mix and 50 presets in five banks.
In the room
Made to sit on the rack.
In session
Warmth, first in the chain
Track vocals and acoustics through Soft; send drums and bass through Hard. Turn on Bass Cut to keep the kick and bass tight while the tubes warm the rest. With HQ MODE off it costs so little you can leave it on every channel.
Specifications
The fine print
| Type | Tube tape-electronics preamp — neural (LSTM) models of the original hardware |
| Character | Soft · Hard |
| Engine | Native 176.4/192 kHz (HQ MODE) or host rate (low-CPU) |
| Formats | VST3, AU, AAX — 64-bit |
| Systems | macOS 10.13+ (Apple Silicon & Intel) · Windows 10+ |
| Controls | Drive, Input Trim, Character, Mix, Output, Bass Cut, HQ Mode, HPF/LPF, AUTO |
| Meter | True VU, 0 VU = −14 dBFS |
| Presets | 50 factory presets in 5 banks · A/B · Undo/Redo |
| License | Online activation · free update for APX-351 owners |
| Trial | 15-day full version, no feature limits |
Try before you buy
The demo is the full plugin for 15 days — decide with your ears.
Bundle value
Also in the Tube Preamp Bundle.
Instant delivery
License and installers arrive by email the moment checkout completes.
Complete your chain
