Considering going back to Solid State

I did read the Stereo times review and I think it warrants further investigation, thank you scott888. Yes the Ayre KX5 twenty is on my short list, being 40 miles from Boulder and having positive dealings with Ayre on C5xe adds favor as well. I realize that I will hear differences in going back to solid state, and once I decide which Pre-amp I would buy, I will re-evaluate then decide. There has some great suggestions here. One of my biggest problems is there are no local dealers for Pass, Coda, Balanced etc. so that makes it tough to audition any of those. And coincidentally I spoke with the Boulder dealer yesterday.

and the search goes on.

theo - If you can afford new, Music Direct owns BAT and gives you a 60 day (I think) window to return -no questions asked.
You might want to check with Upscale Audio who usually has "open box" units at a discount.

Hey Theo,

If you want to audition the Coda 07x preamplifier just give Doug Dale a call.  They sell direct if you do not have a local dealer and I believe you get an audition time and if not satisfied there is a return policy.

Heat really isn't a thing with tube preamps. They make a little heat but its not significant- if that is really a problem you have much bigger fish to fry! Reliability is another thing, but IME you can leave a tube preamp on for some pretty long times (days) and not have any issues. They are not the same as tube power amps in this regard. Our preamps are warmed up very nicely with only an hour of operation so I see no need to leave them on all the time. OTOH many solid state preamps need to be left on continuously as many of them take about a week to warm up.


The problem IMO is there simply aren't any solid state preamps that have the relaxed quality of a good tube preamp. Every one I've heard errs a bit on the sterile side. But if you want some tips, I would be looking for one of two kinds of solid state preamps.


The first is one based entirely on high performance opamps. The reason for this is something called 'Gain Bandwidth Product'. High performance opamps can have a high enough value of that so that the feedback they run is actually capable of also suppressing the distortion caused by the application of their feedback (I know that sounds a bit recursive but that's the way it is). Its a simple fact that in most solid state designs the application of feedback (usually a requirement for them to be linear) causes them to be brighter and harsher than real life because the feedback used is an insufficient qauntity- and therefore unable to correct the distortion it introduces by its application!  If the circuit runs enough feedback it can then be neutral and musical-  without added brightness and harshness (and so sounding like tubes).

The other kind of preamp I would look at would be one that is entirely single-ended, so it can make a 2nd harmonic, and then be otherwise a very simple zero feedback design (probably meaning its MOSFET based) with perhaps only a single transistor and not much else in the line section. This will be a bit less neutral but still have some tube-like qualities owing to the 2nd harmonic and no feedback.

After recently auditioning the well regarded Schiit Audio Aegir amp (driven by curiosity clearly influenced by the extremely positive Stereophile review) in my home rig (meaning I bought the amp and returned it), I’ve moved even more toward the Tubes Just Sound Better camp. I get that SS amp designers like the brilliant Nelson Pass make beautiful sounding gear, with "tube-like" tone and otherwise world class design, I just prefer whatever actual tubes do over what transistors TRY to do. I respect Schiit’s design efforts and use a Freya tube preamp among other items, along with a Dennis Had "Inspire" single ended tube power amp (albeit tied to efficient speakers), and I’m astonished at the results. Pass has described what he thinks is the reason that a tube’s harmonic content and specific distortion profile is what makes things "musical" (or at least maybe more realistic), and I like his philosophy...the way I prefer to apply that philosophy? Tubes. SS has its place with the super clean pro power amps I own, along with a Class D Ampeg bass amp the size of a cereal box (although I’d prefer a tubed SVT but don’t play bass often enough to bother with one), and my great sounding REL subs, but to get the mojo into my earballs I seem to need whatever tubes do...my mind remains open to listen to other stuff here and there, but for my main hifi needs and guitar pickin’ it’s really hard to beat good ol’ tubes.