Joule Electra preamp and Aragon 4004 mkII

I owned both of these pieces, but not at the same time.
The 4004 MkII is a very good value for the money and has held its value amazingly well.
The 4004 MkII has a low'ish input impedance of 22K ohms (similar to some Pass amps).
The LA-150 MkII has adjustable output impedance of either 400 or 1200 ohms.  Most believe a ratio (input/output impedance) of 20 or better is sufficient to prevent audible frequency roll-offs, and some say a ratio as low as 10 should be sufficient.  Your proposed combination should work fine together and you can experiment with the Joule's jumper to determine which output impedance sounds better.
One caveat, many manufacturers report the average output impedance or the value at a frequency of 1,000 Hz, while the highest value can occur at the lowest frequencies, particularly with preamps that use an output coupling capacitor.  Not sure about the Joule but in any case the 400 ohm setting should work fine for you.

Thanks for the responses so far.  Mitch2 thank you. You have been around for a long time in these forums. Some guys can always be counted on!

You are welcome foster.
Let us know how they sound together.

Klipsch claims 101 db sensitivity on that speaker.

I suspect that won't work well with the Aragon. The reason is that the amplifier will be operating for the most part at very low power. Most amps like this make more, not less, distortion at powers of less than about 5-7% of full power, which means that you won't be able to hear what the amp can do unless you play it too loud for comfort.

I recommend an amplifier of less power; no more than 60 watts for sure. If you want to go solid state, some of the First Watt amps made by Nelson Pass would be a better choice, and the JA can drive them just fine.

@foster_9

I think I can help. Reach out to me via e-mail and I can e-mail you a 150MKII manual I have in PDF (the manuals were often copies of copies, so some pages may not be easy to read, but it will do the Job). My Joule Info web-page ( http://sigsound.com/classic-product-info/joule-electra-info-page/ ) has a bunch of product info/literature, but I don't have any manuals up there yet though I do have a number of them (I think they are a few I still need to scan in).

The jumpers in question are the two located towards the rear of the circuit board. The default higher impedance setting is the jumper used on/across the front two (of three) pins. The lower output impedance setting is with the jumpers on the rear most two pins.

P.S. Yes, Joule-Electra is no longer in business - Jud retired and close up shop several years ago. I do provide service, support, and upgrades for Joule-Electra gear (even though it can be very challenging to work on gear with next to no technical documentation!)

Feel free to reach out to me via Audiogon or e-mail, phone etc. I'm not on these forums alot, but will get any audiogon messages.

Cheers
Rich