Is there any way to "pass through" the lexicon and use a tube preamp when I want to listed to the tubes?Yes. Interestingly enough it's called HT pass through, although you pass the HT signal through the stereo pre and on to your Lexicon. There are plenty of balanced (or at least w XLR outputs), tube pre-amps; lots depends on budget. BAT is one obvious choice w a broad range of models at various price points. VAC has pre-amps w XLR out but I am not sure if they are a true balanced differential circuit. Atma-sphere would be a great choice if you want the true balanced circuit. Give us a price range and any other wants/needs and we can make more concrete suggestions.
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Thank you very much for your response. Interestingly enough I saw the lexicon has the ability for "analog pass through" for certain inputs. When I read that last night I was wondering if it would be possible to connect my universal player to a tube preamp, then to the tube preamp to my lexicon (let's say on AUX with analog pass through" set to on, which then connects to my main amps.
If this would work the tube pre would only be used for the universal player which is fine by me. From reading your post it seems like this would not work as the same basic idea is mentioned only opposite: going through the tube first using a HT pass through.
Basically I only want the tubes for 2 ch through my universal player (possible a turntable in the future) and I would prefer the traditional warmer sound of tubes I've heard a few years ago (I've heard some rogue audio tubes recently and it didn't have that vintage tube sound I've heard on on some Cary's about 5 years ago).
My budget would be in the 2k range but I rarely stay in budget and I love the used market where many deals can be found.
I have never used a Lexicon but I am "thinking" that the analog pass-thru feature MAY indicate that those inputs do not route the signal to the digital signal processing section or DACs in the Lexicon. But I "think" it might route the signal thru the volume attenuator so you would have two attenuators in the circuit, generally not considered a good idea. But I'd read your manual on the Lexicon carefully and perhaps even talk to customer service to make sure.
I don't know if Cary has balanced outputs but you already know you like the sound so that is logical. The other plus about Cary is that most of their preamps use 6SN7 tubes extensively. These tubes are readily available as Old Stock even true NOS. You can roll the tubes until you get the sound you want.
I don't know if Conrad Johnson preamps have balanced circuits but many of their older preamps have that warm sound you seem to be hankering for.
Great info guys. I've read up a bit on all of your suggestions and this seems like a very good way to go and best of both worlds as i can use my existing amps/speakers with my current preamp.
some current audiogon tube preamps in the my general price range are:
BAT vk5i (all balanced)
modwright ls100 (nice to have unbalanced and balanced inputs and outputs)
doge audio 8 (has a balanced out, all inputs are unbalanced which is fine)
I've also looked up cary and it seems the slp-03 has the options i need
after careful consideration to all of the great input i received (i can't thank you all enough) the necessary points of emphasis are a tube preamp with balanced outs (having one set of balanced inputs and outputs, the rest can be unbalanced), a HT passthrough (id prefer if this feature can be used while unit is off), which will mate nicely with spectron musician ii monos and anthony gallo ref 3.1 speakers.
Mechans: i did love the Cary products (as well as mccormack and conrad johnson) when i heard them a while back but i haven't heard any of the newer models. I have recently heard a few newer model (rogue, prima luna integrated) and i did not hear that tube sound i remembered from listening to the older model cary, CJ,etc). i thought they sounded wonderful but if i closed my eyes i would have not been able to tell they were tubes. i am not sure if this was because those models sounded bright or simply this is how newer tube models sound. What i loved on my listening session a few years back was the fact that at low volume i could almost feel the breath of Gilmore and the sound of his fingers sliding up and down on the frets on the "wish you were here" track. It sounded like i was sitting front row at a very small venue rather than hearing the sounds from large speakers at a stadium.
Well the difference is that the BAT is a fully differential design, whereas the Cary only has balanced inputs and outputs. What this means is that Cary is not a truly balanced design, you could use any single ended preamp design with RCA to XLR adapters and have the same results.
Now this has nothing to do with sonics at all. I have owned a few BAT preamps, and I am currently using a Cary SLP-98P preamp. Yes the balanced BAT preamps were a bit quieter, but I prefer the musicality of the 6SN7 tubes in the Cary over the BAT 6H30 tubes. You pays yer money, you makes yer choices.
Thanks for the input Jmcgrogan2 , I appreciate it.
Right now I run full balanced from my av pre to my mono amps and I love it. If I were to add a tube pre with a ht bypass that was non balanced would this now make my system unbalanced since it's connected in line? I might be overthinking this a bit but your point makes me wonder. I absolutely love the sound of Conrad Johnson but all of their models are single ended.
Duckman- Not to complicate matters but according to this poston AVS Forum, the MC-12B is not "a 'truely' balanced circuit as Lexicon feels that is the wrong way to build a product. The DACs (on both the MC-12 and MC-12B) are run in dual differential mode, then their outputs are summed right at the output of the DACs. This gives you the maximum S/N increase from running dual differntial DACs. From there the signal is sent out the single ended outputs and to the balanced line drivers." so you may be making an issue out of something that is not really there. There are lots of products w XLR connectors that do not have dual differential circuitry, so you would not need to change all of your ICs but you could widen the field of possibilities.
Yes, a break in the chain in any spot is still a break in the chain. To run a fully differential system the signal must remain fully differential throughout, from beginning to end (source, preamp, amp). Some feel that this is a big deal, but not me. Some of the best systems I've ever heard are single-ended. Whatever floats your boat though.
The Doge 8 (1st version) had noise issues with the phono section. The more current 'Clarity' version is absolutely dead quite - line stage and phono section (even when using Moving Coil carts). My friend has the preamp running a Bel Canto amp and Maggies. I've heard the preamp many times through different amps. No noise issues assuming you have decent tubes.
Demo'd a whole assortment of preamps the past two weeks. i must say most (not all) were very nice, each having their own set of characteristics. i have heard, prima luna , rogue, audio research, cary, aesthetix, ayre and a few others. Of those mentioned i liked the aesthetix calypso and ayre (kx5 i believe) to be the best. i still have not been able to demo any BAT products which i really wanted to. i haven't heard that perfect symmetry with my clad D spectrons but I'm on my way *im trying thats for sure)
Do you have access to a McIntosh dealer? Like you I am considering a tube preamp upgrade (from my Mac C220) and intend to demo the C2500 at some point. That's their top-of-the-line pre insofar as single box units go.
The inclusion of a killer DAC in that preamp may not be something you would use (hence needlessly driving the price up) but it is a large part of the appeal for me as my digital front end (Marantz SA7S1) is 2007 technology.
i believe there is one not too far, ill defiantly inquire. The arc 17se really makes my amp/speakers sound better (best I've heard thus far) but I'm really missing the mid bass i heard with the Ayre. if these were my only two options id keep the arc ,even without the med bass, the highs really sing. I've never heard the Gallos sound this nice at such a low volume.
i am still eager to demo some aesthetic products and i would love to try (no dealer anywhere near me) a modwright.
:) you missed one, in a way the granddaddy of them all.
The Atma-Sphere MP-1 was/is the world's first balanced line preamp, having been introduced in 1989. It is unusual in that it is also all-tube, but has a direct-coupled output, something unusual in any tube preamp. This allows it to be more transparent.
Balanced line operation has certain advantages. If you really want to experience them, whatever preamp you get should have these two characteristics:
1) the output should appear between pins 2 and 3 of the XLR connection, ground being ignored and only used for shielding. This helps reduce the effect of the interconnect cable.
2) the preamp should be comfortable driving low impedance loads. If not, its output impedance can interact with the cable, allowing the cable to color the sound. IOW again we want this to insure cable control and immunity. By 'low impedance loads' I mean 5Kohms or less.
If lacking these characteristics, the preamp will not be able to take advantage of everything the balanced line system has to offer.
For example, the balanced system was created to eliminate cable colorations. Audiophiles have long thrown money at that problem, hoping for a cure, but it was actually solved back in the early 1950s or so (the balanced line system). This allows for long cable lengths (although it still an advantage even if the cable is only 6") and the assurance that as long as the cable is properly built, it will not add or detract from the sound.
This BTW is why audio engineers often scoff at audiophiles that spend several house payments on cables. They know that cables don't make a difference! But they live in a world of balanced lines....
Want proof that this is so? Look to Mercury records or RCA Living Stereo LPs. Quite often the microphone cables were over 100 feet to get to the input of the tape recorder, but the recording is pristine. It is because this problem was solved by balanced lines.