Looking to upgrade my preamp - suggestions?


My system has been coming along pretty nicely since I started putting it together 2 years ago and I am now thinking about upgrading to a better preamp. I'm looking for opinions about which preamp would go well with my Manley 300b neoclassic amps. The Manleys only have RCA inputs (no balanced inputs).

Here are the amp specs:
http://www.manleylabs.com/containerpages/seppneo.html#specs

I am currently using the Manley Shrimp, which I still think is a good unit for the $$$. I'd like to upgrade however because I think a better preamp would improve the bass, give me a bigger soundstange and also improve my ability to hear further into the music. My system now is a bit laid back - many recordings sound like they are coming from a few feet behind the speakers. I would like a bit more forward presentation. The sound is rather neutral which I like. Not looking for an artificially warm tube sound.

I would like to buy in the used market and I'm fairly flexible on price range - $2000-$3000 or so. I would love to own a Conrad Johnson CT5 (or Ref 3) but at $4500 or so (used) its a rather outsized investment relative to other components in my system. I really built my system around the 300b amps :) In my opinion, past $3k on a preamp I would be better served upgrading my speakers?
latinsamba1
Latinsamba1...i mentioned the impedance matching. You want to make sure that the input imedance of your power amp (300B Neo) which is 100Kohms is at least 10X of the output imedance of the preamp you are going to use. That is a min. Many people prefer >=20X. So in the case of the LS-26 it's output impedance is 700 ohms when used through balanced connections and 350 ohms through single ended connections, so no impedance mismatch there. I hope that makes sense. Here is a link to a post that I placed asking about this a while back and the responses I received so hopefully that will help in making it clearer: http://forum.audiogon.com/cgi-bin/fr.pl?aamps&1253079731&&&/Question-re-matching-pre-and-power-amp-i
Thanks Cmalak. I would be using the single ended connections because the amps only have RCA inputs, but that sounds like the LS-26 would work fine.

Question on the gain of the preamp. My Shrimp has 12db of gain which corresponds to turning the volume knob to roughly 9 oclock for my regular listening level. With the gain adjustments on the LS-26 (6,12 and 18db) is there any advantage to running a different gain level in terms of lowering the noise floor?
Yes...with the gain setting on low (6dB), when you move through the volume setting, you get finer gradations in the level than you would at medium gain (12dB) and at high level (18dB). So it just gives you the ability to fine tune levels to where you want them. Also depending on the gain of the amp you are using it with, if the power amp has a high gain setting, you can put the LS-26 on the low gain setting and again that allows you to get finer gradations in level when you move up or down the volume setting. The Ref 3 has single gain setting and when used with a high gain power amp for example, even at the volume level set at 1 notch above mute, you may get too loud a level for late night listening for example. So it just gives you flexibility. Hope that helps.

Is there anyway for you to audition the LS-26 vs the CJ pre in your system before deciding? Even if you just audition at a dealer with a system that is close to yours, it may be instructive to get an idea of the sound. ARC's latest offerings (like the LS-26) are very neutral as compared to other tube offerings and you heard some comments above that referred to ARC gear as lean. So it may be that you may not like or be used to this sonic signature (although I don't think it is lean but I have an all ARC system and so the synergy between the pre and power amp is there). I would at least give it a listen (preferably in your system but if not at a dealer) before deciding to pull the trigger. I personally love the ARC house sound but that is my opinion and listening preference. Others have different opinions. Good luck and let us know how you make out. Take care.
Another very strong vote for the Shindo Aurieges. A 2nd choice would be the line-level Leben. Both should be available used within your price range. Either one could easily be the last preamp you will ever buy. Yes, they are that good!