Tube Phono with Tube Integrated Amp?


what are the drawbacks (if any) of this setup?  

i recently acquired a VPI Prime (amazing) with a Soundsmith Zephyr MKIII.   using a ProJect Tube Box S (which was a phenomenal upgrade for my previous ProJect Carbon table).  right now, running this through a vintage Kenwood KA-9100, powering Elac UniFi's bookshelf speakers. 

i'm looking to build a 2 channel system that i can grow with, so please disregard the amp/speakers for now.  I've read great things about the Manley Chinook and the Allnic H1201.   in the event that i upgrade to a tube integrated amp in the future, is there any downside?
i've read on this forum that a tube phono is better paired with a solid state amp.  



mjb87062017

Showing 5 responses by lewm

If you expand your horizons to consider used equipment, you'd be amazed at what you can acquire for $3K.  Just take a look at the Audiogon listings. I do understand that many are not comfortable with purchasing expensive second hand merchandise.
It wasn't you who attached a negative connotation to the use of FETs. 
As to tubes vs transistors, that's one of the oldest arguments in audio.  But I don't think one should mix technologies with the expectation that out of that mixture one will get the best of both worlds.  There's no guarantee of that.
Jolly, Where do you read that it’s a "thing" to pair a tube preamplifier with a solid state amplifier? I’m just curious, because, as I pointed out, unless you know what you’re doing, it can actually be a bad "thing". If one wants to do it, one needs to know the input impedance of the ss amplifier and the output impedance of the tube preamp. It is not unusual for a solid state amplifier to have an input Z of 10K ohms. If that’s the case, make sure that the tube unit provides an output Z of less than 1000 ohms, the lower below that, the better.  If the SS amplifier has an input Z of 25K ohms or higher, you're usually on safe ground to use a tube preamp.

Lots of "tube" phono stages use an FET or a bipolar transistor at the phono input to boost gain for an LOMC cartridge. So what? This makes it unnecessary to use a SUT with such cartridges. I don’t take this practice as an a priori indictment of the phono stage.
EDIT: In my post of 10:16 AM today, I wrote the following confusing sentence: "Ideally, the ratio between the output impedance of the driving stage should be around 10-fold lower than the input impedance of the amplifier." Obviously, the sentence does not make sense, would better have written, "the output impedance of the driving stage should be around 10-fold lower than the input impedance of the amplifier". Thus the ratio between them would be 1:10.
"i've read on this forum that a tube phono is better paired with a solid state amp."  I don't know where you read that, but on a technical level, the opposite is usually true; if you want both tubes and ss in the signal path, then you are better off using an ss preamplifier to drive a tube amplifier.  This is because the output impedance of tube preamplifiers is generally much higher than that of ss preamplifiers; conversely, the input impedance of a typical SS amplifier is much lower (as much as 10X lower) than that of a typical tube amplifier.  Ideally, the ratio between the output impedance of the driving stage should be around 10-fold lower than the input impedance of the amplifier.  As you can guess, this will not always be the case if you mate a tube phono to a SS amplifier.  The result of such an impedance mismatch is potentially a loss of gain or roll-off in the treble range.  But there is no imperative to mix the two technologies, anyway.  They both play well together, tubes with tubes; SS with SS.

Manley vs Allnic.  Two excellent choices.  You won't go wrong with either, and I think both of them offer limited functionality as line stages. So you would not need to buy a separate line stage, if you only use one other source besides phono.  (Check me out on the specs for the Chinook and the H1201 to be sure in fact that both do offer at least one high level input.  I use a Manley Steelhead, which does have that feature.)  Also, check out the new Atma-sphere phono, with pricing in the same range as the Chinook and H1201.