Recapping an ARC LS-5 mkiii


So I have done an exhaustive Internet search on this, and have some answers (but not all).

Every piece of audio gear I have from the 80's and 90's has had some sort of issue and needed mods and/or repairs. Some of this wasn't audible, but showed up when the equipment was put on a test bench.

Every piece of classic/vintage equipment I have (Aragon, Sonic Frontiers, Audio Research) has been updated except for my LS-5 mkiii preamp. With ARC gear, I know lots of people tend to think of them like classic cars and look down anything ARC didn't do originally.

At the same time, I know ARC offers a Stealth Cap upgrade (roughly $800 IIRC) and I also know Steven Huntley at GNSC used to modify ARC gear (including the LS-5), but I can't really find anything out there on what that process involved.

I am interested in getting the Stealth Caps done, however, outside of that, I don't want to change the sound signature too dramatically (like shoehorning an LS V8 motor into a Mazda RX-7). I'm sure there are some gains to be made (Rel Caps to Infinicaps?), but want to make sure I do things the right way.

BTW, the preamp sounds good (to me), but as I've learned, that doesn't always mean it would test completely within spec.

Thanks in advance.

atlvalet

@atlvalet the fellow that I purchased my LS5 MKIII from lived close to ARC, and also knew someone there. I had him deliver the Unit to ARC so they could check it out at my Cost and then ARC would Ship it to me.

I spoke to the Tech for the Condition of the Unit, and he told me the following.

1) Power Supply Caps will need to be Changed in 5 Years.

2) Rack Mount Faceplate (2 Holes per Side) was Extremely Rare since they did not produce many.

3) Stellar Condition.

The choice is yours if you wish to have this work performed. Your Unit is " Due " on the Power Supply Caps.

If you decide to have the work done, you might also want to look at obtaining some Amperex Holland Tubes. I tried the Russian Tubes initially, and when I tried the Amperex the LS5 really sang.

Scott Frankland is getting Older, so it is up to you whom you wish to perform the Service. After Scott’s work the Sonic Level of my Stereo was ramped up One or Two Notches. The $1K was mice nuts for the Sonic Improvement. Even the Better Half noticed.

@tecknik you are Absolutely Correct that the LS5 MKIII is Very Rare on the Open Market, and it took me 5 Years to find one.

@jafox I am not getting this in my System; " too unnaturally forward sounding and lacks the energy in the low end ". You are Correct that there is Always Better but at what Cost? I actually tried a Highly Regarded Pre since I was not sure if I wanted to Rebuild the LS5 MKIII. Once the decision was made and I received the LS5 back, within a short time the Highly Regarded Pre was Sold. I was that smitten with the Change of the LS5.

I am also getting Older, and I do love to read about Gear while Subscribing to 3 Mags. At my Age I do not wish to get on the Gear Merry Go Around. Trying the New Gear and if Disappointed, the Time and Monies lost pays for the Rebuild of the LS5 MKIII.

Case in point, I have been researching replacing my Classic 60 Amp which I have owned since New. After Months of Research, I do not have a Clue with what to replace it with. Have you seen the Price of the KT150 Tubes lately. I have decided recently that I should just stick with the Lowly 6550 Tube in the Classic 60.

The LS5 MKIII will very likely be my End Game Pre along with the Classic 60 if they do not Fail.

OP:

Honestly don't know the improvement possible there, you'd have to ask some one who has gone through it.  I was speaking from a generalized perspective focused on reliability.

Film caps have a much longer lifespan, and while they _may_ last indefinitely they do sometimes get leaky.  It's the power supply caps I worry about from a reliability perspective. 

If you think the sound quality improvements in the coupling caps worth it that's up to you, but I am afraid I can't offer you guidance. :)


Best,

 

Erik

@djohn It's interesting to hear of Scott Franklin's recommendation here.  I had the ARC SP-10 for 8 years before I switched to the LS5 II, and then the III some years later.

My final showdown with the SP-10 was the MFA Luminescence at a dealer in the mid 1980s.  I remember that session vividly.  The Lummi provided bass extension and authority but lacked much needed extension on the top.  The SP-10 did not at all have the bass authority or portrayed power in the lower mid, but the SP-10's dynamic contrasts were incredible.  The Lummi's strengths were the lower octaves, the SP-10's were in the upper octaves, but both lacked detail in the very top.  The Lummi was more laid back at the speakers with the SP-10 out into the room. I ultimately bought the SP-10, but the Lummi was special.

And then in the mid 90s, the final showdown for an update from the SP-10 was the LS5 II vs. the Sonic Frontiers SFL-2.  The differences were very much the same, and no surprise.....it was the same designers head to head again.  The LS5 did the 3D magic with greater ambiance, but it lacked the authoritative power of the SF.  Notice that I do not use the word, "better".  Both models improved from their older models in the previous shootout, but compromise was still high.  

All these years later, I felt that the forward presentation of the SP-10 and LS5 was not natural.  The ARC's forward presentation can be appealing and addicting, but after 15 years with the ARC products, once I heard a system with the sound back at the speakers and behind, and extended into the top octaves, there was no going back.  The 1980s Counterpoint SA-5 auditioned 10 years ago confirmed this.

Almost 30 years after the LS5's creation, so much refinement has come along where the compromises I have described above no longer need to be made.  If someone is willing to pay $2500ish for an LS5, and put another $1k into an update, there are just too many models available on the used market today at this price that offer a multitude of refinements.

Oh, and I used a Classic 60 loaned by a colleague for almost a year until I dropped in an ARC VT130 amp in the late 90s.  Wow, wow, wow, lovely.  Ahh, the good ol' days.

John

@jafox okay, now this is funny...because I have two differentially balanced preamps.

One is an LS-5 mkiii. The other is...wait for it...an SFL-2 that's been updated by Parts Connexion and had the coupling caps replaced by the previous owner with VCap ODAMs bypassed by CuTF VCaps.

Now, I did a very brief listening test in a terrible room, and I couldn't hear any immediate differences...the LS-5 has EH gold pin 6922 tubes from Upscale Audio and the SFL-2 has some so-so regular EH tubes of unknown provenance with two Reflektors.

Anywho, if you were going to recommend a preamp in the $3500, what would it be? I ask because I am seriously considering sending the LS-5 to Scott F. I've read some reviews that state the mkii had "unatural" mid range bloom that was "fixed" by the mkiii version...but, you know...don't believe anything that you read on the Internet.

I'm also considering replacing the Solen caps in the power supply of the SFL-2 because I'm a tweaker and I can't leave well enough alone LOL

@atlvalet - It’s a small world indeed.

If you are using EH, Soviet, JJ, etc., tubes in your LS5, you have yet to hear its true potential. Do an internet search for the Tube dealer, Brent Jesse. He has given me sound advice on suggestions for several of my tube components over the years.

When I ran with the Aesthetix Callisto & Io models 15 years ago, a mix of Mullard, Telefunken, Amperex and RCA tubes made their way through these as I tried different pairs at each gain stage. Gutting out those horrid Sovtek’s was a major refinement.

I too am a tweaker.  I am a diehard tube roller as my many threads over the years can confirm.  And I recently fully rebuilt the massive crossover boards in a pair of Duntech Sovereigns.  That capacitor review page and other A'gon threads on Resistors steered me into the right directions.

John