Wanting to start a DIY tube amp

[pevelg]

I am wanting to purchase and build this kit:

http://www.bottlehead.com/et/adobespc/S.E.X./SEX.htm

My speakers are Soliloquy 5.0 and was wondering if they would sound good with the kit. My listening environment is a small room. Info on the speakers here:

Frequency response: 45 Hz to 18 kHz
Impedance: 10 ohms Nominal
Sensitivity: 88dB
Bass/Midrange Driver: 5.25" rigid poly fiber cone,
Die cast magnesium baskets and specially vented
Magnet systems. Magnetically shielded.
Tweeter: 1.125" double chamber, silk dome with unique
Proprietary coating applied by hand. Magnetically shielded
Crossover: 3.2 kHz @12 dB/ octave
Physical: 7.5" Width, 14" High, 11" Deep,
Weight: 22 lbs.
Price: $1,395 (with Custom Stand) $895 without.

[vinylkid58]

In order to avoid disappointment, try a low powered SE amp with your speakers before buying a SEX amp. With such a low sensitivity (88dB), they may not get along very well unless you are listening at very low levels.

Jeff

[Richard Ellis]

I must agree with Jeff here, Two watts of output power is just simply too little to work with for your speakers.
Perhaps you should be looking at some 300B variations, maybe a parallel 2A3 set-up or??...something with around 6-9 Watts of power.
Your speakers will really only be suitable for the likes of a computer sound-system (Very close-in) with this little power.
Even so, with Eight watts of power your still looking at only 97Db of SPL.
___________________________________________Rick... ......

[pevelg]

What about the new stereomour tube amp that is getting ready to come out? It supposedly can put out about 3.5 watts. I am currently building a seduction unit for my lp deck and was wanting to build a tube amp next. Are there any other recommended kits or would upgrading my speakers be the better option?

[Glowbug]

3.5 watts and those speakers wouldn't be a great match, IMO, unless you're content with not a lot of unclipped volume.

What about a ST70 or ST35 clone kit from Triode Electronics? http://store.triodestore.com/

Or maybe a Tubelab Simple SE board with EL34s or KT88s...

[BZed]

With 88dB sensitivity you need 16 watts to get 100dB spl out of those speakers. Thats not very loud.

If you wat to use the low power SET amps you will need speakers with 94dB to 98dB sensitivity. Remember for every 3dB increase in sound output you have to double the power.

[pevelg]

How many watts is the ST70? I can build two mono block Mk3 mono tube amps at 60 watts a piece from triode electronics, but that is getting above my price range. Plus, I would like the option of multiple inputs.

[Andy Bartha]

Two watts is not going to work with your speakers. Don't forget with single end amp you do not get to use all of the power because the distortion goes through the roof as you get close to full power out. You can get maybe half the power. So you are really looking at 1 watt not 2. Unless you planning on listening in a closet you will be clipping that 2 watt amp in a heart beat.
You will need either a big single end amp, which will be expensive or a push pull amp. Check out Tubelabs' simple push pull amp. It is all on one board and you can use Edcor outputs and do the whole thing for less than 500 bucks. His website is www.tubelab.com. There is a nice picture of a populated simple P-P board.

[pevelg]

so would the better option be investing in better speakers that have a sensitivity above 94db? From the reading I've done, SE amps are considered much more desirable when compared to others. I have been looking at the tubelab website, but I can't find any kit orders, other than the circuit board.

[Glowbug]

so would the better option be investing in better speakers that have a sensitivity above 94db?

Higher efficiency speakers would allow you to explore more of the tube world, that's for sure. And as long as you can make the size tradeoffs, not needing as much power to reach undistorted reference levels is always a good thing, IMO

SE amps are definitely cool, but there's a ton of good PP amps out there...just depends on the application...

but I can't find any kit orders, other than the circuit board.

He doesn't stock parts. Parts can be found at places like Mouser, Digi-Key, Antique Electronics Supply, PartsConnexion, etc...