Custom Tube Consoles

News

For more than a decade, I have supplied made to measure vacuum tube recording consoles and outboard equipment for studios throughout the world. Circuit designs have matured and stabilised, mechanical designs and component selections that permit system flexibility are now in place. Yet, fully customised designs still take a huge amount of time and effort because just about everything  apart from the bare PCBs has to be designed from scratch. As I approach my 70th birthday I find I no longer have the time nor the inclination to design and build mixers this way. I want to make tube mixers available to a wide range of end users so now I plan to build tube mixers only in one of three forms:

• The Poor Man's Tube Mixer. A minimum cost fully functioning tube mixer  (also suitable for DIY builds). This is based on a standard mechanical frame  work and open sourced PCBs

• The Compact Recording  Console. A mid range all tube console with up to 6 channels all with mic/line inputs, three band EQ, direct outs, inserts and a basic monitor section

• A top of the range Mark 3 tube mixer with 8 to 16 channels with mic/line and tape return inputs, four band EQ , direct outs, inserts, four groups, four Aux sends/returns, and a comprehensive monitor section

I will no longer be accepting advance orders for fully customised consoles. Instead I will build each of the above consoles and, when each one is complete, offer it for sale at which point minor customisations can be made.

I will still provide support the growing band of DIYers out there who are building their own tube based pro audio gear based on my PCBs, many of which are now open source.

And I will also still be supplying groups of basic tube mic pres via the Lunchbox project. This is a standard rack mounting 3U unit containing up to for tube mic pres and an integral power supply.

Introduction

If you are here then I don’t have to explain why you prefer tube sound. Trouble is, there’s not much around in the way of professional tube mixing console products. There are plenty of professional mixing console products with a few tubes in them but they all have semiconductors in the signal path. There are also plenty of professional all tube products - but not one of them is a mixing console. The sad truth is no one makes all tubes consoles - until now. I design and build custom tube consoles. All consoles are designed to order. Each design uses standard physical modules and is created from a series of standard building blocks, but each console is unique. All the designs are based on a few straightforward guiding principles:

• Semiconductors are used in power supplies but there is not a single semiconductor device of any kind in the signal path, not even a semiconductor constant current source or a biasing LED.

• Global negative feedback is not used yet excellent distortion figures are achieved.

• Designs are built from standardised Class A building blocks.

• Channel gain is controlled by switching in pads at appropriate points in the signal path. This allows the user to select between minimising distortion or allowing the introduction of tube tone.

• Passive mixing is used because it avoids negative feedback

• Passive equalisation is used, again because it avoids negative feedback

• All active circuits are built on PCBs which are hand wired inside screened enclosures with attached front panels. This provides maximum screening and signal integrity.

Use the navigation buttons a the top of the page to find out more about specific products, the design philosophy employed, background information or to make contact. #schaefferag #frontpanel