Price Paid:  $3000.00 from Used: 2 years old

Summary:
The LS-25 is a mk.1 with the 6922 tubes. Very good match together with ARC VT-100 mk.2. Wide soundstage, warm midrange. Good dynamics and resolution, but not as good as CJ Premier 16LS and BAT VK-50SE. The soundstage also lacks a little depth compared with the two other.
Rest of my system:
Avalon Avatar loudspeakers, Audio Aero Prima CD, Audio Research VT-100 mk.2, Transparent Audio cables.

Strengths:
Warm midrange, relaxed sound with good dynamics and resolution, not as revealing as BAT.

Weaknesses:
Little soft in the bass, and the soundstage lacks a little depth compared with the two more expensier preamps.

Similar Products Used:
BAT VK-50SE, Conrad Johnson Premier 16LS

Summary:
This amp produce very wide soundstage, excellent resolution,
depth, transparency from top to bottom.
I have never experienced any pre-amp with such good balance and high frequency response. You can't find these in above listed pre-amp.

This gem not only sounds big and wide "horizontally", but also "vertically", with incredible depth.

What surprised me even more when I partnered it with Dynaudio, I though I was playing ribbon speakers! yet full of body.

Strongly recommended!!!!!

Strengths:
Enchanting Midband, Amazing Highs(Very detailed highs with astonished layering!!!), User friendly(Remote and gain control)

Weaknesses:
Lows not as tight as others, but transparent(yes! listen it for yourselves)

Similar Products Used:
VTL Ultimate, S.F. Line 3, Mcintosh C22, Ayre K-1 MK 2, Klyn SK-6

Price Paid:  $5000.00 from Lyric HiFi

Summary:
This pre-amp is the updated LS-25 Mk 2. Having gone thru every type of nos tube substitute for the 6922 I decided to upgrade to the 6H30 tube. The Ls-25 mk 2 preserves all the goodness of NOS Amperex and Siemens tubes in a more consistent product. The biggest improvement with the mk 2 is in the rich harmonics and clearly defined bass lines. The highs are also clear smooth and liquid. The midrange is still the main emphasis of this product but is deeper than the original. I don't use the factory supplied tube damping rings but use another brand that allows more air to enter the sounstage. Best performance will not be achieved until you find the "right" power cord and speaker placement. This is mainly due to the units generous bass potential and rich harmonics. I highly recommend the upgraded version and the upgrade is well worth the price to original LS-25 owners-even if you have found magic with NOS tubes. This pre-amp is a winner.

Strengths:
Rich harmonics, full rythmic bass, extended smooth highs, open deep soundstage, natural palpable midrange and strong dynamics.

Weaknesses:
Extremely revealing of source component colorations and performance varies drastically with aftermarket powercords.

Similar Products Used:
Audible Illusions, ARC LS-15, Original ARC LS-25

Price Paid:  $4600.00 from Cherry Creek Audio

Summary:
Detailed, slightly dry midrange with a wide 3D soundstage, excellent transients, spectacular top end that's not rolled off with a quick tight bass response. Typical Audio research look and feel, attention to detail, built like a tank, will probably live forever. Midrange tones such as vocals are top dead center accurate. Bass is tight and well extended, but a touch dry or lean at the higher bass frequencies. The most transparent, silky smooth top end I've ever heard. The detail is above approach, if there's a weak link in your system or in the source material the LS25 MII is ruthless in revealing these shortcomings. I recommend a slightly warm and rich sounding speakers such as Vandersteens. Stay away from dry detailed speakers such as Thiels.
My equipment consists of; Counterpoint SA-20 Amp, AR LS25 MII preamp, AR PH3 Phono stage, Nakamichi OMS 7II CD player, Vandersteen 3A Signatures w/2WQ Sub. Denon 62L T/T with Denon 103MC and Wire World interconnects.

Strengths:
Midrange Detail, silky smooth top end, quiet, remote

Weaknesses:
I'm still looking

Similar Products Used:
LS17, Hovland

Price Paid:  $5000.00 from audio systems

Summary:
I had the LS25II home for an audition along with the Audible Illusion. The ARC simply sounded bigger with a much more extended top end and extended bass. The real difference though was the midrange. The ARC just sounds beautiful no trace of hardness or glare. The audible Illusion was quite noisy/ARC dead quiet. I also had the ARC LS16 for a while along with a VTL pre again ARC sounded much better to my ears. LS 16 was wonderful but lacked the majic of the 25II. Only wishes volume control takes some getting used to, If only it had a great phono pre onboard (keep dreaming). If you want a really nice tube pre this may be your answer.
System:
ARC LS25II
Sonic Frontiers PowerII
Theta Miles bal.
Martin Logan Prodigy
VPI HW19Jr.
Acurus phono pre
Nordost cables

Strengths:
extreemly quiet, great soundstaging, tonally accurate, smooth, smooth, smooth.

Weaknesses:
none

Similar Products Used:
ARC-LS16, Audible Illusions, VTL, Acurus