Bottlehead S.E.X. 2.1 Amplifier

I have started to assemble my Bottlehead S.E.X. Single Ended eXperimenters kit. This amplifier drives headphones and sensitive speakers. I bought the kit including the impedance as well as the C4S upgrade options. Here are pictures of the build: Impedance switch Constant current source Top plate Completed underside Upper side


Tube Pre-amplifier updates continued

I implemented further improvements to my Bottlehead Quickie. I changed the output coupling capacitors and installed Clarity Caps MR series 2.2 uF. I also reduced the microphonics of the tubes by putting a water pipe clamp around it.

Tube pre-amplifier – updates

I installed some upgrades to my Quickie: I have replaced the stock volume potentiometer with an Alps RK27 100k Ohm. That got rid of a slight channel imbalance and also improved the sound quality noticeably. Additionally, I have replaced the stock RCA 3S4 tubes and installed NOS Telefunken's DL92 (3S4). The next upgrade will be… Continue reading Tube pre-amplifier – updates

Tube Pre-amp

While waiting for parts returning from repair I had ordered and put together a pre-amplifier kit from Bottlehead. I had chosen the "Quickie" kit, which was recommended for first time builders. The kit is inexpensive at $99. The preamp is driven using batteries, and has two input channels. While ordering the kit, I also bought… Continue reading Tube Pre-amp