Passive Preamplifier

A chain in one audio system is commonly consist of a source, pre-amplifier, power amplifier, and a pair of speakers.

Especially between the pre-amplifier and power amplifier, most owners demanding more simple setup like using only an integrated amplifier. This integrated amplifier is including variety of input selection and a volume control and a pre-amplifier circuit inside.

For the purest audiophile, the coloration from the pre-amplifier is avoided. That is why they prefer only using a power amplifier, minimizing extra components that can cause the coloration from it.

With this in mind, they are prefer to use a passive preamplifier to connect to the power amplifier.

Obsolete DIY Audio (Part 2) First Watt B1 Buffer Preamplifier

I continue this topic about what certain do it yourself (DIY) audio that obsolete, means it used to be good but not for today standard.

The First Watt B1 Buffer preamplifier are published around 2008. It is very popular buffer preamplifier among DIY audio at that time and I am the one who also praised it very much. You might probably know the buffer function in audio system, in the First Watt article about this B1, it is explain the function completely by the audio guru, Mr. Nelson Pass. In short, this buffer function is for impedance matching between input and output, from the source to the amplifier.

I always said this is just like a preamplifier but without additional gain. I have made this B1 buffer 3 times in the past and they makes me smile. Mostly I combined this B1 buffer with the Gainclone amplifier. This makes the music more deeper in sound-stage and reveal the details.

For that reason, I will make it again right now.

Counter Point SA-2000 Convert To 220 Volt

The electric outlet in the United States are 110 volt and bring their domestic product to my country which is 220 volt is require the step down transformer, which somehow more complicated and dangerous if you accidentally plug in directly to the wall outlet.

Luckily most of the product are compatible with 220 volt, but need some modification for this voltage conversion. And this is how I do it on the Counterpoint SA-2000 pre-amplifier.

DIY First Watt Nelson Pass B1 Buffer Pre-amplifier

If you into this DIY audio for quite long time, you should already know the audio guru: Nelson Pass with his First Watt products. His idea and concept in making the amplifier is simplicity. All of his amplifier are made by using only few FET transistors. The most important thing about Nelson Pass is he kind enough to shares all his design to this DIY audio community, so you can build one and having the same experience like he did with his design.

Nelson Pass also designing pre-amplifier with the same concept. In this post I will share the B1 buffer pre-amplifier building process. The main function for this buffer pre-amplifier is to match the impedance between input and output. So the next equipment, such as the amplifier can be work optimally.

This B1 buffer pre-amplifier is consist pairs of SK170 FET transistor per channel. It is simple to build without any PCB, or just with a point-to-point connection.