Question for ARC line stage owners

I am trying to determine when ARC started to install IEC connectors on their LS models. As close as I can determine it started around 1997 or 1998. Here is what I have been able to put together so far. It seems that some latter LS15's have it and the early ones don't. Some LS 8's have it and some don't. LS8 mkII's do have it. All the LS7's I have seen don't have. The REF 1's don't. Current LS units like the 16 and 25, and REF 2 I already know have the IEC from the factory. Please tell me if I have this wrong.

I also would like some feedback on when ARC started to install the InfiniCaps in the LS series from the factory?

I am thinking of trading my SP for an LS. I have been toying with the idea of going all digital and won't need the phono section. It may also be an opportunity to go balanced throughout my system. Again, LS 7,8 are single ended. LS 15's are both. and I assume that all of the current stuff is both SE & balanced.

Any thoughts on what other ARC owners felt about the advantages of going balanced in terms of sound are also welcomed. If I decide I don't need to go balanced I can always install an IEC and some InfiniCaps, or the new DynamiCaps in an LS7 and have a nice sounding line stage for a modest price.

If I could I would just buy a REF or a 25 kII but I don't think that is going to happen any time soon. Give me your thoughts.

best bang for your buck
completely balanced setup, very engaging and musical piece
Many feel it's only beaten by the Reference 2.
One can be had for $1800-2300 when someone is willing to part with one. All the ARC magic at a modest price.
Audiotomb, I assume that the LS5 uses 6922's. How many of them? My guess is that the 5 also uses the MIT multicaps. I am curious about the circuit board layout. Is there some space between the MIT caps, or is it very tight like a few other units I have seen. I also would like to know about the back panel. Is the power cord placement such that an IEC could be installed where the original power cord exits and not conflict with the fuse holder and perhaps the transformer inside the unit?

Not an audio engineer
The LS5 takes 10 6922's

I couldn't tell you on the caps, I believe it has them.
I know others who have had their power cord upgraded, yes I believe there is space there.

Steve Huntley of Great Northern Sounds does mods on the LS5, maybe he could help you on that end.

Thanks for the info. I think I would rather stay away from ARC units with 10 tubes or even 8 like the LS 22. I would consider it if the warm up time was not longer than it takes for my ARC VT 50. I have to leave my SP 9 on ALL the time or it sounds dreadful. I think most people that bitch about the sound of the 9(or the LS 1 for that matter, which is the same thing without the phono stage) don't understand this aspect of the unit. If infact I didn't need to leave it on all the time the tube cost wouldn't be so bad. If I do need to leave it on to get the best sound the tube cost will just be too high. What do you do with yours as far as leaving it on and why?
Infinite cap on my LS-15 makes the mid more open and liquid. Using Siemens tube also makes the high smoother and deeper bass. Balance in/out in LS-15 sounds better than SE.

tube warmup isn't too bad on the LS-5
The sound is pretty good right off and really settles quickly.
After an hour you get about 95% of the way there.
I generally come home, turn on the amp and play music then or withing the hour. No long leaving things on unless it's the weekend and I'm home.
I bought a "trade in" ls-15 from my local ARC dealer. It was made late in 1996. It has the IEC cord, InfiCaps and had the black rubber tube dampers. The balanced direct input is the best sounding. I will add that 60's Amperex Holland Bugle Boys in positions V1 and V2, followed by 60's Amperex 6922 PQ's in V3 and V4, sounds pretty damn good!
I would go balanced as it is a better connection as well as quieter. I had Infinicaps installed in 1997 as an upgrade to the VT130. With the mods you suggest, you may be very happy as spending a lot of money for a certain nuance in sound doesn't make sense. For example, the Russian 6H23 is an incredible improvement over the stock 6922s for little money. With experimentation, you can taylor most ARC gear to your liking. As far as IECs, call Leonard at ARC. He can answer any questions you ask.
Hi, Catpenny -

I will second your observation on the substitution of 6H23s for 6922s - they make a substantial difference for the approx $200 cost (vendor: Upscale Audio). For my LS22r, this meant improved transparency, smoother top end and more liquid midrange. Bass seemd mre defined as well. Having said that, I still get the best results when I bypass the preamp altogether, running an Accuphase DP-75 directly into a Pass X350 via balanced lines. The improvement in tonal texture, sound stage and definition is nothing short of astonishing.
The Dynamicaps were used to replace all the MIT Multicaps ( coupling caps) in both the line and phono stage of my ARC SP9-MKIII. The stock power cord ( 18 ga) was replaced with a PS Audio mini lab 10 ga triple shielded cord. A Furutech gold plated IEC was installed and it was wired to the main circuit board with high grade oxygen free copper wire. The mode, balance control and tape switches were all bypassed with litz wire. I never used these switches/controls so it was worth bypassing these for the much improved preformance. The chassis and circuit boards were damped. The power transformer was also damped. Tubes were upgraded to NOS Seimens 6922 in both line and phono stages and new ARC tube dampeners were installed. OEM rubber feet were replaced with superior compounded rubber feet ( slightling smaller in circumferance) for better isolation. These feet also have less surface contact than the stock feet. Unit was put on pneumatic isolation device being a Seismic Sink. Air pressure was adjusted for maximum vertical isolation ( original Seismic Sink 1D circa 1997 model) Power supply capacitors ( stock SP9MKIII) were hotglued together for a much improved dampening effect. Other mods were done but these were the vast majority of the upgrades performed by a couple friends of mine who are in the audio business and have worked with and for major audiophile OEM's for many years. For the first time the recording XRCD Jazz At The Pawnshop sounds awesome. It really sounds like you are there for the first time. Before the mods it sounded very harsh. Noticed improvements in presence, soundstage depth and width, instrument focus, a full 2 octaves of lower bass. Piano notes sound like the real thing. Very close to the Steinway studio my wife plays. Noticed better low end bass detail and previous hardness on the upper end is now a thing of the past. Dynamicap .01 bypasses are highly recomended for this application and provide crystal clear and extremely quick upper end detail. Musical passages are substantially quicker as compared to the stock ARC SP9MKIII. I would highly recomend doing this mod. Why spend 8 grand when you can have something close for just $1,600.00.I bought my SP9MKIII used and the mods ran around $800.00 or so. The cost value relationship was worth it to me.