Best budget phono preamp for Unison Unico?

I just finished building the Bottlehead Seduction phono preamp! I haven't even had the chance to try it out yet (need to buy some interconnects) but I had a lot of fun putting it together. I'll report back with a fuller account when I've had the chance to test it out in the system.
Rebbi (Threads | Answers)

I'd love to hear your impressions. Please report back.

Sure, I'm happy to oblige, and thanks for the reminder!

First of all, let me say that there is a particular kind of satisfaction in building something like this yourself. I have to add that I, myself, had not even held a soldering iron since I was a teenager, so I approached the project with not a little bit of trepidation. The manufacturer has a rating system of 1, 2, and 3, 1 being a beginner level kit, and 3 being a kit that requires more experience/expertise. The Seduction phono preamp kit is rated "2." Working on the kit sporadically, due to my work schedule, it took me a week or so to assemble the kit, not counting the wooden case. I like doing things like this, and my own manual dexterity is pretty good (although my aging eyes necessitated my taking my glasses off quite a bit, even with bifocals, to do some of the finer soldering work). All that said, the assembly instructions are excellent, and the Bottlehead support bulletin board is full of extremely helpful folks, including the president of the company, so there are plenty of people in easy reach to hold your hand if you run into trouble. Actually, there is only one part of this particular kit that's especially challenging, and that's attaching and soldering a series of tiny little capacitors to some tube socket terminals. Challenging... but hardly impossible, and a source of real satisfaction once you get it right. I think I also should add that in addition to the $275 cost of the kit, you have to factor in (if you don't already have these things) the cost of buying a soldering iron, solder, needle nose pliers, wood glue, wood stained and varnish, and so on. Depending on how crazy you go with these things, you're probably looking at close to another $100, give or take.

Of course, what you want to hear about is the sound of the finished kit. I think it sounds terrific, but I have to insert the caveat that I haven't had a lot of other phono stages to compare this with. The only other phono stage I've ever spent extensive time with was the one that came built into my ancient, PS Audio solid-state integrated amp from the mid-1980s, and I haven't listened to that one in years. That being said, the Seduction sounds to me like you would expect a high quality tube phono stage to sound: round and dimensional, lush, beautiful midrange and so on. I like it so much that I have already ordered a $75 upgrade kit, which is supposed to be a pretty easy add-on project. It is supposed to tighten up the bass response, make the kit somewhat quieter than it already is (which is pretty quiet) and it also adds several decibels of additional gain, giving you a little more wiggle room in terms of the output of your photo cartridge. (I am using an Ortofon 2M "Blue" moving magnet cartridge.)

I'd be happy to answer any other questions that anyone has. Let me also say that the kit is pretty sharp looking once you put it together! :-)

I think the Musical Surroundings Phenomena beat the Cambrdge, at a little more $$.

Hi Rebbi,

I assume you built your Seduction with stock parts. The C4S upgrade is significant. Great that you're getting it. If you send me your address offline, I'll send you a pair of 0.1 uF Russian teflon FT-3's that you can use for input caps. I have an extra pair that I'm willing to give you. These are poor man V-caps. They cost about $8 each, but sound fabulous. The other significant caps to upgrade are 0.47 uF for the output. Mundorf Silver/Oil are the way to go for this position. There are several other tweaks you can make that don't cost much:

- a 220 uF Black Gate in the power supply.
- a transformer choke replacing a resistor in the power supply.
- a pair of 47k ohm Texas Components TX2352 resistor the input load:

http://www.texascomponents.com/

Chashmal, for what it's worth, the Phonomena and Cambridge 640P aren't in the same league as the Seduction. They're good phono stages, but they don't have a silky smooth midrange like the Seduction. I also found the Seduction to have more spacious three dimensional imaging... among other things.