What tubes for ARC LS 5 preamp - 6922/6DJ8


I'm a neophyte as far as tube rolling goes
I have an ARC LS 5 preamp which has 10 6922/6DJ8 tubes

I currently have the Soltek 6922 Russian tubes that Arc stocks in their units

can anyone recommend a tube or combinations of tubes to achieve warmth, transparency, tonal balance, richness etc.
(less transistor like - more musicality)

probably not looking at the ultra expensive, but the best bang for the buck a step or two above the stock solteks

also can anyone recommend an online vendor or audiogon member who sells quality tubes at reasonable rates

thanks a lot

Unfortunately this is a very difficult tube to get as NOS and the ones that sound good are continuing to increase in price. There are no good new 6DJ8 / 6922 / 7308 tubes being manufactured (in my opinion).

The Amperex 7308 may be best for your needs. This was a military tube, stunningly clean, very fast and very low distortion. When I owned ARC it was my overall favorite. The only other choice might be the Siemens E288CC. I have a bunch of these and run them in certain audio gear, not sure if the ARC will "digest" them though.

For the Amperex (USA) 7308, contact Bruce Wenger at BWS Tube. 703-536-3910. He has a large supply of the Amperex and E288CC Siemens as well. He may know if the ARC circuit supports the Siemens. His web link below:

I'd second the nomination of Amperex, but everything they make is great, 6DJ8, 6922 and 7308. 6DJ8's are nice, their earliest type (Bugle boy, etc.) is not crazy money. Let me know if you need some, I have at least 10 I can part with. Check my feedback if you need confirmation.

That is a good suggestion and offer for you Audiotomb. The tube Ed is suggesting absolutely will work in that circuit and is a bit warmer than the Military 7308.

Either will murder the Sovtek you have been listening to.
Be careful with the 7308s in the LS5mkI/II. I tried the
Amperex 7308 gold pins in my LS5mkII and they rang like a
bell. And these were brand new NOS hand-selected low
noise/microphonic from Kevin Deal. Nothing at all wrong
with the tubes. There's some sort of plate current
incompatibilty going on there. I would stick with 6922s
for your LS5mkI/II to be safe.

But don't be so quick to dismiss the Sovtek 6922. I've used
a lot of different 6922s in my LS5mkII. The Sovteks are
quite good. Another decent less-expensive NOS 6922 is the
JAN Philips.
Good to see you here again Tom.

When I got my first LS5, the MK II, I put in RAM Labs 6DJ8 that I had purchased years ago for my SP10. The RAM tubes added a little more warmth and smoothness to the stock LS5 tubes at the time....I am not sure if they were sovteks then....this was early 1995. You might want to contact RAM to see if they still have such tubes. http://www.ramlabs-musicreference.com/index.htm

A few years later I tried the Amperex and these worked well but I do not recall much of an improvement here. I bought these from a private party so perhaps they were beyond their prime. And so when a couple of these died, I ended up buying the Sovteks and the LS5's character was pretty much the same.

Just last year, I was able to audition the MK III against my MK II in my home as a local audiophile was looking to sell his MK III. And we compared to his LS22 also in my system. It was quite interesting to jump between the 3 preamps, all warmed up a couple hours before listening.

As Albert refers to the other tubes murdering the Sovtek, both LS5s did this to the 22, and then I would say the MK III severely wounded the II. The III amazingly enough had all of the II's midrange magic in tact and yet the III had far more resolution in the lower mids, but more importantly, the III had a natural top end. Unfortunately the II has an exaggerated top end with too much sibilance. After listening to the III for awhile, it was truly difficult to return to the II.....and I had owned a II for 5+ years. The II however did seem to have more extension in the bass .... perhaps this too was exaggerated.

So my point to all this is, before you go out and spend a fortune on tubes, you might want to keep your eyes out for a III. I might even go out on a limb and predict the III with the Sovteks would beat the II in any tube configuration. Albert may rightfully so correct me on this, but the sound of both units with Sovteks was similar and yet the III was clearly in a whole new league. I can only imagine what the III might sound like if Albert and Ed are correct about the other tubes. I just might give Ed a ring too!

Happy to see you finally said adios to the LS2. Right on!

Hello John
and thanks ALbert and Ed

John, good seeing you here again and thanks for all the preamp advice.

I bought the LS5 mk II a year ago and love it
actually I am looking at Steve Huntley of Great Northern Sound to upgrade my mkII. http://www.greatnorthernsound.com/home.htm

Steve does significant upgrades to the ARC products. Steve used to work for Audio Research in the design phase and does significant upgrades to ARC, Wadia and other high end pieces. His philosophy is that ARC made some cost saving corner cutting and newer technology exists to make these pieces sound significantly better. Steve is from your neck of the woods in Minnesota and is very helpful. Send him an email and find out about his mod program. I have a friend who Steve did a mod on for his LS22, it was much more open and musical than the stock unit. He also is a big fan of the LS 5 in the chain of ARC products.


amperex golden globe jan 7308s made such a difference in my ls 5 mk 2 that i retubed my vt130 w/ 7308s as well. my only comparisons are sovtek 6922 but the difference was huge so i'm shopping for more 7308s.
JJ makes a 6922 that is warmer than the Sovteks and is very reasonably priced.
WOW this thread is right up my alley.
I have owned an LS5 MK II for the last few years.
I recently had it at Great Northern Sounds for the Reference upgrade package. I also run it with Amperex white label 7308's. WOW WOW WOW
All the beautiful liquid accuaracy but no grain. Not a hint. The bass is meaningful and fast. Soundstage is accurate and detailed. WOW WOW WOW

Steve Huntley is a very nice man to boot. He has a great ear and listens to good music. I saw his shop first hand and would recommend him most highly. The LS 5MK II deserves to have this upgrade done to it. It is already a classic and this modification lowers the noise floor and tweaks an already advanced platform. It is world class all over again. No fatique but not mushy. The 7308's are a must for this pre. It sucks to have to come up with 10 NOS tubes at retube time but the sound is worth the insanity.
The telefunkens sound quite good too. Happy hunting.

thanks for the post

how much of the sound improvement do you attribute to the Great Northern Sound upgrade and how much to the tube replacement???

would be interested to hear more on Steve's upgrade