Audio Horizons TP 2.0 Preamplifier

Hey Bill! Congrats on finding the tubes that sound best for you. Enjoy the preamp.

We should probably note that there may be safety concerns in having the top removed, for the unit and for the cat! I am not sure that it would lessen vibration effects. But there is plenty of room to try vibration dampening material pasted to the underside of the top metal piece. RxMan I admire your experimental curiosity. I am tempted to cut a piece of plexiglass and compare it to a piece of real glass - both should be easily made to seat with the nice rim around the top. But how about heat disipation from the tubes?

Audio Horizons Lovers. Tried asking this question at cable section but dont get much response. Maybe U can help. Have anybody try changing Exactpower Conditioner or APS Purepower stock PC to Transparency PC and observe any improvement in their system? I m from Malaysia, so borrowing it for a 30days trial I dont think is applicable to me. Yr input is much appreciated. Happy listening

Gammajo (and others)

The lid I created is 3/4" thick gloss black, acrylic.

I routed a step along the underside perimeter, so it (sits in) the top of the preamp with no screw holes.

The weight alone is plenty for safety reasons or whatever (yeah, I have a cat)

I lined the underside lip with adhesive-back felt strips, for a cushion between it and the top edge of the chassis.

Gaps were left between the strip ends for ventilation purposes, the preamp only gets luke warm, nothing to be concerned about here.

Personally, I think it looks so good, I wouldn't mind manufacturing a few one-offs or supplying dimensions for interested DIY-ers.

My supplier is a local plastic and fabricator shop, they roughed out the initial cut, I finished it.

It took *many-after-work-hours* on the Bridgeport, cutting, shaving and fine tuning for a perfect fit.

It's very hard to upload a good picture (since it's black) but in person, it looks beautiful.

As Gammajo notes, safety is one very good reason to leave a cover on the preamp (or any electronic device with 120V running into it).
Joseph has told me about another benefit of keeping the cover on the unit: it helps the signal to noise by minimizing radiation distribution within the unit. If all other factors are held constant, the signal to noise will be better with the cover on the preamp.
The Audio Horizons chassis is quite rigid. I like, especially, the welds at the chassis corners which greatly enhance the rigidity. I have not sensed any audible vibration from the cover of my preamp. However, if that is a concern to you then do use some adhesive backed damping strips. Doing so can only enhance the benefits of the preamp.