Audio Research LS25MKII Preamplifier Preamplifiers

4.8/5 (5 Reviews) MSRP : $5495.00


Product Description

Having held a firm position in our product lineup for two-and-a-half years, the LS25 has proved highly popular for both its musicality and its many features and system flexibility. With recent engineering breakthroughs at Audio Research, however -- especially stemming from the development of the VTM200 input stage technology -- it became increasingly clear that the venerable LS25 was the perfect preamplifier candidate for these latest performance enhancements. Because it already has so many useful control functions, the LS25MKII remains almost entirely unchanged in its exterior configuration -- meaning original units can be updated at the factory to the MKII spec. Inside, however, you will find a new motherboard architecture that incorporates a JFET input stage similar to that used in the VTM200, followed by a cathode-follower / output driver stage using two 6H30 twin triodes.


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Reviews 1 - 5 (5 Reviews Total)

User Reviews

Overall Rating:5
Value Rating:4
Submitted by highend75 a AudioPhile

Date Reviewed: January 3, 2007

Bottom Line:   
The LS25 MkII very high quality, places stiff challenges to all of the known competition.
Sound stage is huge and 3-dimensional with lots of detail, stereo imaging is excellent, one can actually hear the positioning of the instruments and voices as they were recorded. The music has weight and dimension. The bass is deep and well defined, bass lines can be followed naturally (it’s right in front of you) without being mushy and rounded. Mid’s are incredibly realistic and non aggressive, gives the real sensation of the musicians and instruments being there. The treble is smooth but very detailed.
Overall the sound is smooth without loosing detail and being fatiguing. I found myself listening for hours and hours.
And, what’s most important of all, the timbre of the instruments and voices are faithfully reproduced.
This pre-amp has the best of both worlds solid state (FET stage) and tube (output stage).
Like all tube pre-amps the sound can be easily transformed with a different set of tubes and since there are only 2, experimenting will not ruin your bank account.
Controls: this pre-amp has a control for everything - sensitivity of each input, balanced or single ended, etc., it’s a luxury that once you get used to, you can’t live without. It’s something highly appreciated.
It is built to very high standards, solidly and with the highest quality parts.
Customer Service at ARC is very helpful. Leonard is always ready to help when there is any question or issue. They also sell direct the original tube sets (always good to buy direct and avoid distributor fees) and take credit cards for payment.
On the con side: the unit is very sensitive to mains fluctuation. It can mute outputs and go completely unresponsive with a variation of voltage above 10%.
The remote is not to the same standard of quality of the unit itself. It’s mostly plastic and tends to go out of order with use. ARC should offer a better remote (or at least an optional remote for a price).

Expand full review >>

Used product for:   1 to 3 months

Duration Product Used:   AudioPhile

Product model year:   2001

Price Paid:    $3000.00

Purchased At:   Pre-owned



Overall Rating:4
Value Rating:5
Submitted by Highend75 a AudioPhile

Date Reviewed: December 31, 2006

Bottom Line:   
The LS25 MkII very high quality, places stiff challenges to all of the known competition.
Sound stage is huge and 3-dimensional with lots of detail, stereo imaging is excellent, one can actually hear the positioning of the instruments and voices as they were recorded. The music has weight and dimension. The bass is deep and well defined, bass lines can be followed naturally (it’s right in front of you) without being mushy and rounded. Mid’s are incredibly realistic and non aggressive, gives the real sensation of the musicians and instruments being there. The treble is smooth but very detailed.
Overall the sound is smooth without loosing detail and being fatiguing. I found myself listening for hours and hours.
And, what’s most important of all, the timbre of the instruments and voices are faithfully reproduced.
This pre-amp has the best of both worlds solid state (FET stage) and tube (output stage).
Like all tube pre-amps the sound can be easily transformed with a different set of tubes and since there are only 2, experimenting will not ruin your bank account.
Controls: this pre-amp has a control for everything - sensitivity of each input, balanced or single ended, etc., it’s a luxury that once you get used to, you can’t live without. It’s something highly appreciated.
It is built to very high standards, solidly and with the highest quality parts.
Customer Service at ARC is very helpful. Leonard is always ready to help when there is any question or issue. They also sell direct the original tube sets (always good to buy direct and avoid distributor fees) and take credit cards for payment.
On the con side: the unit is very sensitive to mains fluctuation. It can mute outputs and go completely unresponsive with a variation of voltage above 10%.
The remote is not to the same standard of quality of the unit itself. It’s mostly plastic and tends to go out of order with use. ARC should offer a better remote (or at least an optional remote for a price).

Expand full review >>

Used product for:   1 to 3 months

Duration Product Used:   AudioPhile

Product model year:   2001

Price Paid:    $3000.00

Purchased At:   Pre-owned



Overall Rating:5
Value Rating:5
Submitted by tubes2you a Audio Enthusiast

Date Reviewed: October 2, 2006

Bottom Line:   
When I read a review I sometimes wish I knew a little more about the reviewer and their experience with different types or brands of equipment. Part of owning an expensive piece of equipment is the "pride" associated with owning it. I know I have had this feeling from time to time. When I buy somethiing that I have streached the bank to buy I want to feel good about the purchace, instead of getting it home and finding out I really don't like it and wish should had bought something else. When someone streches their bank it is probably the best peice of equipment they have ever owned, and they naturally give the equipment a shinning review, yet someone else who has more expericne, differnet tastes or has spent a lot more money (some how we relate expense to sound quality, so far I have found this to be true, but it's not always the case) may have better equipment and may find the rating only satisfactory at best.

So with that in mind, I have lived with mid-fi most of my life. I don't have a lot of experience with many different high end preamps. I didn't streach the bank to buy the LS25 MKII, but it is the most I have spent on a preamp. It is by far the best preamp I have ever owned and it made the biggest single improvemnt to my system. Source material has a lot to do with it but...finially the speakers disappear, creating a wall of sound. There is significantly more detail, front to back imaging, increased dynamics, wow! A wide sound stage, crisp attack and speed. It's smooth, it's really smooth and totally engaging! I love it. Now... I have never had an ARC REF 3 preamp in my system, and Yes, I would probably like it better, but until I try it, I will probably be very happy. My preamp was the weakest link in my system and I am sure the LS25 MKII only complements the rest of my system. You may not have the same reaction using different equipment. I like most types of music, I preferJazz for the most part, I don't care for poor quality recordings or RAP, NO RAP!

My system as is: Linn LP12/Ittock LVII/Denon DL-103D/Creek OBH
Marantz SA8260 SACD
ARC LS25 MKII
ARC VT200
ARC D400 MKII
Magnepan 3.6/sound anchor stands
2- DIY Madisound/NHT 1259 woofers
Dahlquist DQLP-1{low pass only)
Richard Gray PRO400
Analysis Plus Oval 9
Kimber Hero's.

I will upgrade to balanced cables when I find what I want.

Expand full review >>

Used product for:   1 to 3 months

Duration Product Used:   Audio Enthusiast

Product model year:   2005

Price Paid:    $2800.00

Purchased At:   audiogon



Overall Rating:5
Value Rating:2
Submitted by Art S a AudioPhile

Date Reviewed: June 18, 2004

Bottom Line:   
Very excellent preamp. Flexible and useful feature set, has plenty of inputs/outputs. Well-built as usual from ARC, and drop-dead looks.

There may be some miniscule improvements with ARC's Reference models, but I'm not sure in what areas of the presentation and at what price.

Does anybody really need a $10,000 audio preamplifier??? Or a $5000. one for that matter?

Expand full review >>

Used product for:   1 to 3 months

Duration Product Used:   AudioPhile

Product model year:   2001

Price Paid:    $4000.00

Purchased At:   pre-owned



Overall Rating:5
Value Rating:5
Submitted by EdMa a AudioPhile

Date Reviewed: May 28, 2003

Bottom Line:   
after having had a lot of very expensive and not satisfying preamps. i stumbled on the ls 25mk2 i heard a friends ref 1. i cannot say that this is the best preamp but i will think twice no maybe three times to even listen to a transister preamp again. this preamp is really very very very good. it will deliver you what it is all about and that is MUSIC. no artificial hifisound. what i find that all transisterpreamps i have heard sound sharp in the upper range and they sound as if you are behind the musicians and not in front off them. Super natural sound.

Expand full review >>

Used product for:   Less than 1 month

Duration Product Used:   AudioPhile

Product model year:   2003

Price Paid:    $7000.00

Purchased At:   holland ( price in e




Reviews 1 - 5 (5 Reviews Total)

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