I get a great deal of enjoyment poring over photos and descriptions of other peoples' builds. In that vein, it is my turn to return the favor, and post some photos and comments regarding my own humble experience building the SP14.
I bought the beautifully made circuit board from Roy and began ordering components from different sources. The basic circuit board assembly was straight forward.
A number of years ago, I bought a rough radio case on Ebay, with the idea of repairing the woodwork and installing a tube buffered gainclone amp that I had made in it.
The amp ended up living it's life in a wine box instead, and the radio case got used as a sort of end table.
I decided to build the SP14 into the old radio case. I built a chassis that I could slide into the case easily without modifying it.
I left the chassis out of the case for a time while I spent time swapping output capacitors and tubes, playing with how the combinations varied the sound. In the end, I didn't like any combination of bypass capacitors that I could come up with, and ended up with the Audyn, True Copper, 1.5uf caps in the main output position.
At the same time, I began obsessing about what tubes to get. I was intrigued by favorable comments regarding the E-1148/VT232 tubes, so I got a dozen of those from a vendor in Lithuania. I contacted another vendor in China, and had him send me four adapters disassembled so that I could modify them to fit in the SP14 space available.
Now, I am enjoying swapping in and out different valves, which so clearly imprint their character on the sound.
I only have a couple of Mutt n Jeff pairs of 6SN7 and some 7N7 to try with the VT232 at the moment. I bought some adapters to try 6F8Gs too, but haven't bought any yet.
As others have stated, the particular sound of a tube is slightly more pronounced when placed in the input position, as opposed to the same tube in the secondary position.
I had a very nice Marantz 7 that I sold to make this preamp, and I am not missing it in anything other than a nostalgic way. I am very happy.
This is a link to some photos; https://photos.app.goo.gl/lcx6bDbwUUDEKkpH3
Last edited by Fitero on Sat Sep 09, 2017 1:57 am; edited 1 time in total (Reason for editing : new photo link)