Pricing and availability

We compare 600+ stores and found this item at 3 stores. Prices updated .

Average Price: $5,699

High-end/Boutique

$100

$501+

Price Tier

Budget

Standard

High-end

Price History

Based on price data from 3 merchants for "Whitestone P331 Tube Loading Amplifier". Prices shown reflect NEW condition. Tracking began Apr 2, 2026.

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Description

The Whitestone P331 Tube Loading Amplifier is a sonic marvel designed for discerning audio professionals seeking to infuse their productions with a touch of vintage warmth. Bridging the gap between classic analog sound and modern digital precision, this amplifier is a versatile addition to any studio arsenal. Whether you're tracking, mixing, or mastering, the P331 adds a distinctive character to your audio, enhancing it with subtle harmonic coloration and depth that traditional gear can't replicate.

At the core of the P331 are 6SN7 vacuum tubes, celebrated for their ability to produce nuanced harmonic excitement without introducing unwanted distortion. The amplifier's high-voltage, linear power supply offers unwavering audio integrity, while its digitally controlled analog design ensures precision and repeatability—a must for high-stakes professional applications. The P331's dual-mode loading circuit, with its Clean and Bloom modes, allows users to tailor the harmonic enhancement to their specific needs, offering both subtle nonlinearities and rich even-order harmonics.

For added flexibility, the P331 features a three-mode Auto-Padding system, ensuring your signal remains balanced as gain increases. The Lift circuit further enhances your sound by selectively boosting specific frequency ranges. With switchable output transformers, you have the choice of a clean, transformerless path or two color-enhanced options. The low-distortion, fully balanced solid-state output amplifier provides up to 11dB of boost or cut, with a Resolution mode for fine-tuning.

Key Features:

  • 6SN7 vacuum tubes for nuanced harmonic excitement
  • High-voltage, linear power supply for audio integrity
  • Digitally controlled analog design for precision
  • Dual-mode loading circuit: Clean and Bloom
  • Three-mode Auto-Padding feature
  • Lift circuit for frequency enhancement
  • Switchable output transformers
  • Low-distortion, fully balanced solid-state output amplifier
  • 11dB of boost or cut in 1dB increments with Resolution mode
  • Hard-wire bypass for each section and global bypass option

Owner's manual

Whitestone P331 Tube Loading Amplifier User Manual

Product specs

Number of Channels 2

FAQs

What is the primary function of the Whitestone P331 Tube Loading Amplifier?

The Whitestone P331 Tube Loading Amplifier is designed to enhance audio signals by adding tube warmth and character, making it ideal for recording and mixing applications.

How many channels does the Whitestone P331 Tube Loading Amplifier have?

The Whitestone P331 Tube Loading Amplifier features two channels, allowing for dual mono or stereo processing of audio signals.

Is the Whitestone P331 Tube Loading Amplifier suitable for mastering?

Yes, the Whitestone P331 is suitable for mastering, providing subtle tube coloration and dynamics control to enhance the final mix.

Can the Whitestone P331 Tube Loading Amplifier be used on individual tracks during mixing?

Absolutely, the Whitestone P331 can be used on individual tracks to add warmth and depth, making it versatile for both individual tracks and full mixes.

What kind of power supply does the Whitestone P331 Tube Loading Amplifier require?

The Whitestone P331 Tube Loading Amplifier typically requires a standard AC power supply, but it is advisable to check the manufacturer's specifications for exact requirements.

Sound On Sound magazine

Sound On Sound magazine

Whitestone Audio P331 - AES 2018

Video thumbnail for Whitestone Audio P331 - AES 2018 by Sound On Sound magazine

Whitestone Audio P331 - AES 2018

Sound On Sound magazine

Sound On Sound magazine

Video thumbnail for Whitestone® Audio Instruments P331 Tube Loading Amplifier (2022) by Whitestone Audio Instruments

Whitestone® Audio Instruments P331 Tube Loading Amplifier (2022)

Whitestone Audio Instruments

Whitestone Audio Instruments

Video thumbnail for P331 Tube Loading Amplifier Demo (Indie Pop) by Whitestone Audio Instruments

P331 Tube Loading Amplifier Demo (Indie Pop)

Whitestone Audio Instruments

Whitestone Audio Instruments

Video thumbnail for Greg Calbi - P331 Tube Loading Amplifier (2) by Whitestone Audio Instruments

Greg Calbi - P331 Tube Loading Amplifier (2)

Whitestone Audio Instruments

Whitestone Audio Instruments

Video thumbnail for P331 Tube Loading Amplifier Demo (Alt Folk) by Whitestone Audio Instruments

P331 Tube Loading Amplifier Demo (Alt Folk)

Whitestone Audio Instruments

Whitestone Audio Instruments

Video thumbnail for Greg Calbi - P331 Tube Loading Amplifier (1) by Whitestone Audio Instruments

Greg Calbi - P331 Tube Loading Amplifier (1)

Whitestone Audio Instruments

Whitestone Audio Instruments

Video thumbnail for Whitestone P331 Tube Loading Amplifier - Gearslutz @ AES by Gearspace Forum

Whitestone P331 Tube Loading Amplifier - Gearslutz @ AES

Gearspace Forum

Gearspace Forum

Video thumbnail for P331 Tube Loading Amplifier Demo (Rock) by Whitestone Audio Instruments

P331 Tube Loading Amplifier Demo (Rock)

Whitestone Audio Instruments

Whitestone Audio Instruments

Reviews

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Artist usage

Add artist
See how Reinier Zonneveld uses Whitestone P331 Tube Loading Amplifier

Reinier Zonneveld

Music Producer, DJ

...
Verified via YouTube

In this Youtube video we see Zonneveld making an Acid Techno Track from scratch in his studio. He explains how he works and how he uses different pieces of equipment. The P331 is seen throughout the video for example at 16:30.

See how Natalie Bibby uses Whitestone P331 Tube Loading Amplifier

Natalie Bibby

Audio Engineer

...
Verified via Photo

The Whitestone P331 Tube Loading Amplifier is confirmed to be used by audio engineer Natalie Bibby, as it is visible in her studio in an image shared by AIR Mastering on Instagram.

Genre Usage

Based on how artists on Equipboard use this gear, it is most commonly found in the following genres.

Used With

Based on how musicians on Equipboard use Whitestone P331 Tube Loading Amplifier, it is most commonly used with the following gear.

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