Concert Experience for $5k?

P.S: The GoldenEar Triton One which has been suggested by a couple of posters will also not be a good match for your amp, especially if you use the amp’s higher powered ultralinear mode (since as indicated in the measurements I linked to the amp’s ultralinear mode has much higher output impedance, which is referred to by Stereophile as "source impedance," than triode mode). The impedance curve for the Triton One is shown here:

www.stereophile.com/content/goldenear-technology-triton-one-loudspeaker-measurements

In this case, the result of the interaction between the amp’s very high output impedance (especially in ultralinear mode) and the speaker’s variation of impedance over the frequency range would be an under-emphasis of the mid-bass region, and excessive brightness in the upper mid-range.

I have no particular knowledge of the speakers that have been suggested other than the ones I have specifically addressed (Legacy Focus 20/20, some Zu models, Triton One). But again, unless a speaker is known to have a relatively flat impedance curve I would caution against assuming it would sound similar with your amplifier to how it sounds with most other amplifiers, including most other tube amplifiers.

Regards,
-- Al

Maybe t-bon3 doesn't have as much "horsepower" as he thought, huh Al?

John (Jmcgrogan2), as you probably realize but others may not, it’s not a matter of horsepower (i.e., watts). It’s a matter of the effects of amplifier output impedance on tonality, resulting from the interaction of that output impedance with the variations of the speaker’s impedance over the frequency range.

BTW, there are of course quite a few speakers having relatively flat impedance curves, as well as relatively high sensitivity, that I would expect to be great matches for this amp. Including the Daedalus speakers I use, and I believe also models from Coincident, Tannoy, and others. But I have no specific suggestions to offer that I feel confident would provide the sonic character the OP is looking for (I am mostly a classical music listener, not a rock concert-goer), and that would also meet his price point.

Best regards,
-- Al

VanL Quartettes  from Van L Speakerworks (chicago) fit right in your price range and outperform speakers at a much higher price point.   These spekers returned many of us to the joy of the music ... 

Go try the Zu. They have many models, one of them might suit you. Regardless of the model, you will get that "live concert " experience. I own a pair of Zu Omen Def because I was exactly searching for that "live " effect and I'm more than happy!