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Preamp help for First Watt J2/ZU Omens combo

Hi, I'm an all analog guy.  Just a turntable with a phono pre.  I bought a First Watt J2 a couple of months ago and can't seem to find the right preamp.  My speakers are high efficiency ZU Audio Omen Mk2's.  I tried a luminous audio axiom passive and while the midrange would blow you away not much else was there.  I also tried a Schiit Freya which comes with a passive and tube side....passive side real weak and the tube side is like drinking from a fire hydrant.  It's detailed but really in your face and forward.  Very fatiguing.  The people with Pass/First Watt all say a PASS preamp will do the trick like an older X-1 or the like but those are expensive still and kinda out of my budget right now.  Plus, buying used there is not much of a return policy if it doesn't work out.    Trying to keep it $1000 or less. But, it needs to sound right too so If I need to jump up I could. Any help would be greatly appreciated! 
128x128tk78
kalali's avatar
kalali
1,977 posts
 

What phono preamp do you have? The matching between that and the line preamp is also a consideration. The J2 gain figure also appears to be a higher than average and its behavior is just like a current-source tube amplifier so most high-gain preamps will probably overload the system causing harshness.

It should sound real nice with the full-range single driver speakers like Zu.

tk78's avatar
tk78 OP
6 posts
 
Thanks kalali.  It's a Parks Audio budgie hybrid.  It has 46db of gain so maybe that is a little too much and could be contributing to the harshness?
kalali's avatar
kalali
1,977 posts
 

When you say "passive side is too weak", are you referring to the volume/gain or its just somewhat lifeless, the latter being my experience using a passive preamp or a direct-to-amplifier arrangement. As for the gain match, I’d leave judgment to the experts but the 46dB gain does appear fairly high feeding into an amplifier with a 20dB gain.

By the way, as a fan of full-range single driver speakers, I’ve been particularly very curious about the FW J2 since it’s supposed to be an excellent match with that design of speakers. If you get a chance, read Nelson’s technical article about current-source amplifiers and how they interact with full-range drivers. Its posted on the First Watt site. Its one of his earlier articles published in 2004. Take your time in finding a good matching preamp. It’ll be worth the effort.

Good luck.

tk78's avatar
tk78 OP
6 posts
 
Well the passive I first used was a luminous axiom and while the midrange was strong and powerful everything else was lacking.  Bass was there but lacked any punch.  So the phono pre I am running is the newer model by Shannon parks and 46db of gain the older model is only 38.  A buddy of mine has one and I switched it out this afternoon and all the fowardness was gone.  I already sent my Schiit Freya back but wish I would have held onto it a little longer as I should have thought to switch out phono pre’s to a lesser gain.  Im thinking now I can start moving forward with better answers.  Thanks for everyone’s input!
kalali's avatar
kalali
1,977 posts
 
Just as another option, you may want to look at Mapletree Audio preamplifiers. They are beautifully built and very reasonably priced. You can also specify the gain if you order one new and are willing to wait a few weeks. Aric Audio is another shop where you can have one built to order. Both are all tube all hand made units and can be upgraded as much as your budget allows. I have one of Aric's preamps and really like its sound.
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