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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 OP
46 posts
 

@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

jafox
1,447 posts
 

@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

jafox
1,447 posts
 

Oh, I forgot to answer your question.  My consideration/audition list would include:

  1. BAT VK51SE
  2. BAT VK52SE
  3. Cary SLP-05
  4. Vac Renaissance Signature
  5. CAT SL-1 (Many variations)
  6. CJ Premier 16

 

djohn
64 posts
 

@jafox - Absolutely Loved your writings and Thank You! for showing up to the Party.

I was also dead chuffed that you put up with the Classic 60 for a Year. My Classic 60 is very unique since Scott Frankland installed 2 Test Ports on Each Side, and 2 Bias Pots on each side of the Back Deck. I can Bias the Amp myself now with a Voltmeter since I was so sick and tired of lugging the Amp down to Scott's Shop.

I will certainly look at your consideration/audition List for the Pre's in the next little while. I did look at the ARC VT130 Amp that you mentioned and it will not work for me. I am also facing constraints with my Rack which I will not get rid of. When I look at potential replacements I also need to look at the visual & operational aspects, Width, Depth, and Height.

For my Amp replacement in the ARC Line, I love the Looks of the REF75SE but the constraint there is the Tubes. It is a Bigger Unit but it would work especially with the aspect of Biasing it from the Front which is a huge plus.

@atlvalet - I would suggest that if you are considering sending your LS5 to Scott Frankland that you ask Scott his Schedule to do the work. I had to reserve a spot and wait 3 Months. Just saying.

jafox " Nailed It " on the Tubes and also the Vendor to approach. When I switched from the Russian Tubes in the LS5 to these which were sourced from Brent Jessee if was like the LS5 " Woke Up ".

LS5 loves these;

6DJ8 Philips or Amperex, "A" frame top getter. Made in Holland.MATCHED PAIRS

New Old Stock original box. This "A" frame getter version is becoming increasingly scarce. These are all Heerlen Holland Amperex made, and labels are good to excellent. These are said to have lower microphonics, thanks to the heavy, rigid construction of the "A" frame getter support above the plates. These pairs are carefully matched for Gm and plate current within 1-2 percent. These have Amperex, Philips, Miniwatt, and other labels, all Amperex made. Grab a pair now! SINGLE TUBES ARE $40.00 EACH.

$85.00 per pair

In Stock

 

atlvalet OP
46 posts
 

Thanks @djohn. I'll make sure I do that re: Scott.

Also, I went with the gold pin EH tubes because that's what Upscale has as their recommendation for the 6922 tubes on their site re: ARC equipment.

I will contact Brent Jesse about tube recs for the LS-5 and the SFL-2. I know that Chris Johnson recommends the Reflecktor tubes for the SF gear...but I'm interested to know what Brent says.

Appreciate the preamp reccos @jafox.

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