Absorb Gels

What are they? They are valve-base decouplers which allow you to mount a B9A tube (of the ECC83 / 12AX7 fitting) on a compliant rather than rigid base.

At first sight, these little beauties may not strike a chord with the ‘Wow’ factor, but then, in reality, they will most likely be tucked away, hidden inside the dark (or in the case of tube pre-amps, not-so-dark) recesses of the outer casing.

Absorb Gels are simply add-ons. They have on the bottom 9 pins, just like the base of a 9-pin valve. There is a squidgy centre part, and in the top a 9-pin valve socket. Their overall height is about 18mm when inserted, but their beauty lies not in their appearance, but in their performance. They take some burning in, and the first twenty hours or so are a tad so-so, but once warmed through they start to reveal their virtues.

Back in the annals of the past many pre-amps used valve bases decoupled from the chassis by a very compliant rubber insert. Although the pin-connection part was relatively rigid, as were the base’s mounting points, the rubber between the two was distinctly pliable. This meant that, in the days of all-metal construction, the ‘ringing’ characteristic of the chassis could be virtually eliminated. The venerable Quad QCII was one such among many, though the 22 dispensed with them. I have in fact converted one 22 to use the original compliant mounts a la QCII with amazingly good results.

BUT, the Absorb Gels are even better. The noise floor is lower. The hint of ‘clang’ is entirely absent, and the feeling of openness and space in the musical presentation is enhanced to a great degree.

They also work extremely well in phono stages, where the additional damping and ‘gentle restriction’ of the tube does wonders for all that elusive low-level detail. Gone is the metallic or ceramic hash of rigid mounting, replaced instead with a liquid involving and musical presentation. Dynamics are decidedly NOT compressed, and feel even more vivid than before, and the range of tonal colour is enhanced beyond a standard base.

The only area where you have to be careful in a pre-amp is in the available height above the original tube base. If clearances are tight, you may not be able to fit them, but if you can, then do. They are an investment really worth hankering after, and for a very modest outlay, you won’t want to go back to ‘standard’ bases.

In power amps, where a B9A driver or phase splitter tube is used the effect is similar, but to a lesser degree. In these situations the tubes are usually carrying larger signals with respect to noise, so the benefits feel a little less marked, and their effect on power tubes (EL84 / 6BQ5) was less pronounced again. It was still there, but although I had no problems using them under EL84s, the high temperature of the EL84 made me query their ultimate suitability in this particular application.

Overall, this is a five-star () product. For a relatively modest outlay a significant improvement can be achieved, and this can be transferred from pre to pre as your mood takes you.

A word of warning, however. Don’t expect these gizmos to transform your dull-grey preamp into a technicolour one, but do look out for more music, and longer listening sessions. And do be prepared for a higher electricity bill, though, as you may be a lot more reluctant to turn your system off after they have been run in.