Hi there..
whew! It took about two days but I finally read the whole thread.
Just installed an STX into my music server. Setup is 2-ch STX going into a
Dared SL-2000A preamp (2005 Auricap version) feeding a "
Bob Latino" Dynaco VTA ST-70 (both with choice NOS tubes) powering a pair of
Tekton Designs OB4.5 with the tweeter upgrade. The second line out of the preamp feeding a pair of Polk DSWmicroPRO2000 subs. I love many aspects of this setup. I chose the OB4.5's for their promise of a large SS and high level of detail and coherence esp. at lower volumes. They combine the desirable aspects of a single driver speaker and an open baffle design. The subs are dialed in just right to round out the bottom. The tube gear was purchased after much research into finding "affordable gems" and the subsequent tube-rolling roller coaster was an adventure that got rather expensive by the end! I've got a pile of all the usual "12AT7" suspects to prove it too.
Up till now I've been just using a spare USB sound card (Audiotrak MAYA44 USB) I had left over from previous DJ rigs. Knowing this was the weak link, I've had my eye on an STX for awhile now. It wasn't until after I purchased it that I started looking into the whole opamp thing, which brought me to the thread.
Of course my first impressions of the card with the stock opamps are very positive. A marked improvement over the USB card! However, my experience with tube rolling begs the questions of "what will make it even better?"
In the process of reading this thread I managed to take a couple stabs @ getting some different chips making their way to me.
I've got a couple LME4927NA's, 2x AD8620AR on adapters, and an LT1057CN8. I think the AD8620's were a misguided choice from some random post I found elsewhere. I think the 4927NA's will be right in the I/V position, but I'm still trying to determine what's going to be a best-guess for the buffer. (I use the line out only, no headphones)
What am I after?
I love the warm tube sound. But I know even within that there are many varying degrees. Overall I am after a more balanced, detailed (but not harsh/bright) sound with extension in all directions.
I listen to electronic dance music almost exclusively. A clarity and control in the bass is crucial. Many people think that for rap/techno/etc you just want big bass, but I disagree. The fact that the music focuses so much on bass demands that area be under control and clean.
Between the tubes and the Tekton's I've got plenty of oomph in the midrange, this area receives a lot of attention by their very nature. Because the midrange is accentuated, the clarity and detail that is fed to it is crucial as well. They are very revealing!
Part of my grueling 12AT7-rolling was some attempts to tune the mids right, but also get the highs defined, clear, extended, but not harsh. With 3 different places to put the 12AT7 family in my setup you can only imagine the number of combinations and configurations I had to go through to get it "just right".
My concern is only the the 4970NA's are going to throw too much out there on the highs and maybe make the mids a little too hard(?). I'm not too concerned with the bass being lower in apparent volume as long as it pulls it in nice and tight. The Polk subs have some more to offer in volume so I can easily dial them up a bit to compensate volume.
I'm imagining I want a buffer that maybe "warms" the NA's, smooths out the highs and (if it's not too much to ask) pulls the bass back up without squashing the definition too.
I'd thought maybe the LT1057CN8 was a good choice for the buffer, but further reading shows I should have maybe got the LT1057ACN8 (or was it CA), and that they it might not even be ideal in the buffer.
Any other candidates?
I can't see myself doing any soldering so sticking with DIP8 for now is necessary. I'm fine if this leaves out some of the better choices for now. I'm thinking just a little better sound out of the STX will be "enough" at this point. Just knowing I did *something* and got a sound I like better than stock should be enough for my ego ATM
I don't know if it means anything to most of you, the 12AT7 tubes I'm running are Telefunken ECC801S's in the preamp, a 1962 RCA 12AT7W in the middle voltage amp position of the ST70 and Siemens ECC801S Triple Mica's on the 2 phase splitter/inverters of the ST70. The ST70 is running Gold Lion KT-66's.
Maybe if you know the general characteristics of their sound you can divine where my ears like to be....
I am here for biased opinions and their justifying arguments
Thank you.
