What's the greatest bargain in SET these days?


Hi, Gang,
I response to my recent review of the Reference 3A De Capo BE speaker, someone wrote that if you really want to hear them sing, you should try them with a SET amp, or words to that effect.
That got me thinking. The De Capo's are 92 db efficient, which (correct me if I'm wrong) seems kind of borderline for low-power SET amps.
In any event, right now I'm running mine with a pair of Manley Mahi mono-blocks. They are switchable from triode (20 watts) to "ultra linear" (40 watts). I run them in triode all the time, and in my room, the volume knob almost never goes past 9 o'clock; more would just be too loud.
All that said, what do you guys think of running the De Capo's with a SET amp? And if I did, what's the best bargain in SET's these days?
Thanks!
rebbi

Showing 16 responses by jetrexpro

Rebbi, If you built the bottle head you can build a 300b amp kit. Audio Note Kits have some nice 300b amps to choose from. Tube Audio Labs have some good amps as well. The great thing about building your own is that you can change the flavor of the sound to your liking by changing a resistor or capacitor in the circuit or power supply. Start with very good power supply. Get very good output trannys or at least good ones to start with. Lundahl makes very good iron and so does Electra-Print. Changing parts and iron as funds allow.
Rebbi,
Enjoy the kit1. I borrowed a kit 1 a few years back and that was what ultimately pushed me toward a 300b amp of my own. I remember the day very well, it took about 5 minutes of listening to that amp to know that was the direction I wanted to go.. Congrats!!
Jet.
Rebbi, As for stepped attenuators you can also check out Goldpoint. Around $150. As mentioned above it is one of the most important parts of your amp.
Jet.
Rebbi, One thing I do before soldering any part be it a resistor or capacitor into the circuit, I measure it with my DMV to make sure it measures what it is supposed. That will give you added peace of mind. Some parts will not measure correctly once they are installed. This will also sus out any parts that are defective before they are installed.
Rebbi, Reading your blog today and seeing your installation of the tube sockets. Its a ton of fun building gear, right?
regards Jet.
I may have mentioned this before, but if you find something about the sound of the amp that bothers you or you feel could be improved, now that you have a working knowledge of the circuit, it is very simple to try a different cap or resistor and this will alter the sound. Much less expensive than buying a different set of interconnects or speaker cables.
...and attracted to a soldering gun and ohm meter! A rare woman indeed! We should all be that lucky!:) Jet
Have never heard a direct coupled 300b. There is an electra-print direct coupled 300b amp on ebay now. the auction ends today
Gannyring, 1 hour left. You can go to the electra-print website and see the schematic. Very tempting but I have no idea how it sounds - Jet
Lots of direct coupled 45 and 2A3 SET amps but not too many 300b amps. Harder to drive a 300b tube without a cap or an interstage transformer. Plus a direct coupled amp has to be done just right or all sorts of bad things can happen of there is a parts or tube failure. As Charles points out, Electra-Print amps must sound really good and have a great reputation but we dont seem to hear very much about them. Their transformers are more well known.
Yep and that's one of the drawbacks of direct coupled amps...the B+ is usually very high. Especially for a 300b amp.
Grannyring, If you have the spare parts building one would be a challenge but it would probably sound great. Plus you have Jack's notes on the power supply and transformer choice.
Grannyring, I am thinking about building a 2nd 300b amp. I am not sure a PSE amp can be switched to a SE amp. The output transformers usually have different primary impedance for PSE and SE amps the the current rating for PSE will be much higher than SE. I would ask Jack at Electra-Print or Mike at Magnaquest about this
Rebbi, I have following this thread and want to add my congratulations. I would have not believed how good 8 watts can sound for all types of music and I know you are experiencing that kind of musicality that connects at a very basic emotional level. I am still taken aback at how involving rock music can be on a SET amp. Are you a Pink Floyd fan? Please listen to a David Gilmour guitar solo on your SET amp and be transported to the spirituality of that kind of musicianship. Regards-Jet