bFly-Audio Pure-Tube – Device Absorber for Tube Amplifiers

The bFly-Audio Pure-Tube is a device absorber tuned to the higher operating temperatures and weight of tube amplifiers.

It builds on the same seven-layer MLA construction as the regular Pure, but is engineered in material and load capacity so it stays reliably durable even under heavy, heat-generating tube equipment.

Why the Pure-Tube?

Tube amplifiers bring two challenges that a normal absorber doesn't solve ideally: they're often heavier than transistor devices, and they get noticeably hotter in operation. The Pure-Tube is sized for exactly this load profile, with the same seven damping layers of cork, Sorbothane and special rubber as the standard Pure.

What you hear

More calm in the background, a cleaner image and fewer microphonic effects – tube amplifiers in particular react especially clearly to external vibration because of their sensitive vacuum tubes.

Who is the Pure-Tube for (and who isn't it for)?

Exactly right for tube pre- and power amps that noticeably benefit from decoupling. Bottom line: for transistor devices without tubes, the regular Pure is the better fit and usually the more sensible choice price-wise too – the Pure-Tube is specifically tuned to tube load profiles, not generally "the better" version.

Our verdict

If you own a tube amplifier and have ever experienced how it reacts to a knock on the rack, you immediately understand why there's a dedicated version here. Which size and mounting fits your device is something we're happy to work out with you at HD Zürisee in Wädenswil.

Technical data

• Type: device absorber for tube amplifiers, MLA technology (Multi Layer Adjustment)
• Construction: 6 materials across 7 layers – cork with natural rubber, aluminium body, cork with natural rubber, Sorbothane with parallel air chamber, special rubber, aluminium cap, gel pad
• Diameter: 44 mm
• Height: selectable 17, 24 or 31 mm (please specify in the order note)
• Load capacity per absorber: Pure-Tube-0 up to 12 kg · Pure-Tube-1 up to 35 kg · Pure-Tube-2 up to 55 kg
• Mounting: without thread (freestanding, height freely selectable) or with M4, M5, M6 or M8 thread (CHF 30 surcharge per set) – selectable directly here on the page; threaded versions are automatically supplied in the dedicated 24 mm height
• Colours: Aluminium Silver or Black
• Manufacturer: bFly-Audio, Germany
• Included: 4 absorbers in a case, in your chosen colour, size and thread version

Frequently asked questions

What's the difference to the regular Pure?

Both work with the same seven-layer MLA construction, but the Pure-Tube is specifically tuned to the weight and heat generation of tube equipment. For transistor amplifiers without tubes, the regular Pure is usually enough.

What size fits my tube amplifier?

Again, the weight per contact point is decisive: Pure-Tube-0 carries up to 12 kg, Pure-Tube-1 up to 35 kg, Pure-Tube-2 up to 55 kg. Weigh your device and divide by the number of feet, then select directly here on the page.

Does the Pure-Tube handle the heat from tubes long-term?

Yes, that's exactly what it's built for – the choice of materials accounts for the higher operating temperatures that tube equipment generates during continuous use. A normal safety distance between tubes and housing still makes sense, though.

Can I also screw the Pure-Tube in place?

Yes, you choose directly here on the page between no thread and M4, M5, M6 or M8 thread (CHF 30 surcharge per set). The threaded version is automatically supplied in the dedicated 24 mm height.

Why buy the bFly-Audio Pure-Tube at HD Zürisee?

Tube amplifiers are sensitive devices where decoupling is especially worthwhile – we advise you on whether your model benefits and which size fits. Call, write, or reach us on WhatsApp, from our practice in Wädenswil.

Goes well with

More absorbers for transistor equipment can be found with the Pure, more on the topic under Decoupling and HiFi Furniture.