What are good speakers to go with Dynaco ST-70?

[erocfx]

What would be a good pair of speakers to make to go with a Dynaco ST-70. I am looking for music listening, in a living room. Mostly Jazz, blues and classical.

Thanks,
Eroc

[JonMarsh]

Given the power, and high output impedance, you ideally need speakers that are reasonably sensitive, and fairly well damped without requiring a low source driving impedance. Ideally, a fairly smooth impedance curve, too. (I've built and owned ST-70's in the past... the rather distant past though. (70's).

Unfortunately, not all of the DIY projects I've seen have impedance curve measurements for the finished system. The reason why that's important is because tube amplifiers have relatively high output impedance, and interact more with the frequency response of the speaker- high impedance point, higher output level.

Also, you haven't specified your budget or real SPL goals. For higher sensitivity, you generally need bigger boxes- you might want to start by looking at the Statement designs and variations, see if they're close to what you are looking for and willing to build. Also, budget?

[erocfx]

I was thinking moderate SPL goals. I know its not a high powered amp, so I am realistic about that. Statements are probably high on my budget. What about Mini Statements or Finalists?

[dar47]

Troels, does some wave guided transmission line high efficiency designs for tubes.

http://www.troelsgravesen.dk/QUATTRO.htm

[Carl V]

Seas A26 10" 2-way Kit PAIR (based on the classic A25)

Simple....retro...


Perhaps a Coaxial Design based
on an emminece 10" Beta dirver
This driver has been used in a couple
of European deigns.

http://wlm.redwineaudio.com/products/diva

http://www.6moons.com/audioreviews/wlm/divamonitor.html

I built a set of speakers with these drivers
based on an Aidre XO & Modified by the DIYCable Anarchy
company.

or one of the B&C 10" Coaxials.
They make decent Wedge Monitors.

[erocfx]

you wrote "you ideally need speakers that are reasonably sensitive".

Can you define that? Would Mini-statements or Finalist work?

[JonMarsh]

That's up to you and how you listen to music, and how much you want to push your ST-70. Mini statements seem to be about 82 dB per 1 watt drive, based on posted data- to be expected given BSC and crossover insertion loss. You'd need to run the Dynaco on the 4 ohm tap, which halves the output voltage. Solid state amps put out close to the same voltage with a 4 ohm as 8 ohm load, so output usually goes up with a 4 ohm speaker like these. On a 4 ohm tap, the ST70 will put out about the same voltage as a 20-25 watt solid state amp. So, it all depends on what you need in terms of playback volume.

[JonMarsh]

Another moderate price design you might want to check out is Jiim's Anthology design- a relatively new lower cost build from him and Curt.