To use a preamp with my Line Magnetic 805 integrated amp, or not?

I've only tried one preamp with my LM805ia and that's the VAC Renaissance MKV.  Pretty substantial improvement over running the LM as an integrated.  I really was hoping that I didn't hear a huge difference because I could have sold my VAC and been many dollars ahead, but alas the VAC just adds so much to the clarity, size, and depth of soundstage - it can't be ignored and I'm "stuck" with it.

I’ve tried a few different preamps with my LM-508ia, including LTA mircrozotl preamplifier. The preamp that made the biggest difference was when I inserted the Coda 07x linestage in my system. Amazing combo. 

If the pre-in input does not bypass the LM's preamp circuitry, I doubt any external preamp will improve the sound through that input.  Does the LM have a tape input?  That bypasses the line circuitry in a number of preamps I'm aware of.  If it does, try that input.

Just a quick update here. I did work with Don to get the preamp fixed and this was sent back to me to try with my Line Magnetic. After about a week of extensive listening, I struggled to hear a big difference between using the preamp on the pre-in vs just having the source go directly into the LM. It didn't make it sound any worse but it wasn't the large improvement I had hoped for. I can only think that the reason for this is due to the Line Magnetic's configuration where the preamp is not bypassed even when using the pre-in input. That is likely the limiting factor. 

Will it be any different if I used another preamp? Not sure. But I know that the Don Sach's didn't have the effect that I wanted to hear unfortunately. Don is a great guy to work with though! Maybe in the future I will go for his pre and amp combo but for now, I'll be returning his preamp. 

I had decided on a Don Sach's Model 2 preamp to try. Unfortunately, due to some damage during shipping, I won't be able to give this experiment a try. Haven't even tried plugging it in due to fear of damaging it more. 

@rcprince I am looking at trying :) I think this will be an experiment of sorts. I’m unsure of what difference adding an external preamp will make but it seems that the success rate of adding a pre to an integrated is very dependent on the system. Won’t know until I try it out.

@wig I actually really, really enjoy my LM but perhaps it is the case of not knowing what I don’t know. I have compared the LM to Naim, McIntosh, Primaluna, Hegel, Modwright, etc and liked the LM by far more than the rest. Great to hear that you like Don's stuff so much though! I might bite and get his preamp to try. 

I would try before I made any change.  You're adding additional circuitry and connections (generally not advisable) to what seems to be a pretty decent preamp in the LM, plus you will have the added expense of (and angst in choosing the right) interconnects for the combination.  You might have trouble keeping the synergy already built into the LM. 

@wig Ah! Did you end up ever trying the Don Sach's DS2 preamp with your LM at all? It is rare to find someone that has tried an external preamp with the 508/805. 

Congrats on your combo btw. I bet it sounds delicious. 

I was going to run Don Sach's DS2 Tube Pre-Amp with my LM805 but decided to go all in for Don's Combo, Kootenay 120 KT88 Amp along with his Pre-Amp is Outstanding!

Wig

After some research and some good bed time reading, I think I've narrowed the field down to these preamps that may be worth trying with my integrated LM. 

• Don Sach's Model 2
• deHavilland Ultraverve 3
• Linear Tube microZOTL MZ3 or Preamplifier

All three/four have gotten some rave reviews and supporters. Range of price between $2.5 - $4.4k. 

Thanks @jperry Sounds like Shindo's are a very popular option. I have considered a few based on some good bedtime reading on the forums including: 

• PS Audio BHK Preamp
• Audio Research LS27 Preamp
• Don Sachs Model 2 Preamp
• Melody PB101 Preamp
• Modwright LS100 Preamp
• Luxman C700 or C900 Preamp
• Linear Tube MZ2

Does anyone have any experience pairing these preamps up with their tube amps? Would love to hear your thoughts.

I have heard that amp with a Shindo Aurieges preamp. I thought it was a great sounding combination