The PAIA Tubehead is a stereo valve preamp. It is supplied in a kit format, with all the parts speerately bagged and identified. A detailed and well laid out manual completes the contents of the (large) box.
I will start with the manual. I would be a happy man if all manuals supplied with equipment was this good. It is divided roughly in to two halves. The first half of the manual covers construction. The second half of the manual is concerned with the units' operation. Construction is relatively untasking, and if you can solder up an audio cable, you have the necessary skills to produce this kit. Each step is explained in details, with tick boxes to let you know that you have completed each stage. Excellent diagrams are also available.
Operation is simplicity itself. Each channel has only 3 controls, Drive, Blend and output. The drive control sets the amount of tube saturation, the blend control sets the mix between tube tube saturation and direct sound and the output control sets the overall output.
The only metering available shows whether the input to the Ic's are being clipped and consist of a single LED for each channel. Grouped with these LED's are a power switch and associated 'power on LED'.
The tubes used in the tubehead are Sovtek 12AX7, which are the same tubes used by many major manufacturers, including TLA. They are warm and musical. They are also widely available from many stores, such as maplin
The Tubehead sounds fantastic on almost any source, with sounds varying from just being warmed to being crushed and distorted in a most pleasant way! I have found though that clean monophonic sounds work best, and that dense sounds (such as pads) can easily be over done.
I did however, find a couple of problems. The first is that as the kit is designed for the States, you need to change the PSU (you can get replacements cheaply from Maplin in the UK) to an alternative that is suitable for your own countries power requirements. So thats another wall wart to find space for! The second is an issue dealing with tax. When the kit is sent from the States, customs and excise will slap a tax value on it, which must be promtly paid. Unfortunately this adds almost 1/4 again to the price. But don't be dettered. Even at this price it is a bargain.
The tubehead, though, is a fantastic piece of kit! Construction is simple, and can be completed at a leisurly pace across two or three evenings. The unit, once built, looks very professional, coming as it does with a pre prepared 1U rack strip. And best of all, the sound is blinding. On almost EVERYTHING (If used in moderation) is can show improvements to the sounds and all the while adding a nice warm analogue glow! Distortion increases in a slow logarithmic fashion, as would be expected for tubes, and used subtly can add a lovely hint of distortion at the top end of clean sounds. Try it on a bell, and you will see what i mean! There is also a certain appreciation to be gained from using a piece of equipment that you have built. And if it goes wrong YOU can fix it. So no more waiting weeks for Turnkey to do the job! HIGHLY RECCOMMENDED.