Audio Research REF 3

Dear all ARC REF 3 owners,
I just bought an REF 3 preamp which has replaced my LS25MKII preamp. To be honest i'm little disappointed by the result so far, but i guess tubes have to be replaced. My concern is especially on the sound image which is not precise as my LS25MKII image was.
The number of hours of used displayed by the my REF 3 is 1670 but i realized that hours counter increased only for full hours of used, so i can estimate the number of hours of the tubes inside my REF 3 to be the double i guess.
My question is the following
What do you recommend for tubes replacement and source for the replacement of REF 3 tubes.
I used sovtek, EH gold, and 6H30-DR on my LS25MKII and i was pleased with all those tubes even if i didn't find the DR much better than the 2 other brands.
Thanks in advance
How did you come to your conclusion on how the clock works? I would have thought that while the time is only displayed to the nearest hour, the timer starts up exactly where it left off.
I also moved up from the LS25MKII to the REF 3 and the difference was astounding. Thus, I have not had any motivation to experiment with other tubes. I'll be interested in what you learn.
The tubes should be fine for at least 4000 hours.Did you buy used,previous owner may have reset the counter to "0"Check with Audio Research technical support.
It's probably your power tube. The stock 6550 power tube is run fairly hot and runs out of steam at about 1100 hours--clarity and dynamics diminish. You need a matched replacement 6550 tube from Audio Research. They will want the number written on your 6550 power tube and the cost is about $85. Your small signal tubes have a longer life span, so I doubt that the problem lies with them. I owned a Ref3 for about 8 months and replaced the 6550 tube twice, before selling the unit. It should sound much better than the LS25MKII. The problem of "running out of steam" isn't something that is well known, but if you do an Audiogon search, you'll see it talked about. Good luck. Best regards, Stan
I agree with Talon, my dad owns the Ref3 and while there has been alot said about it your experience isnt the norm, Seeing how you bought it used the only hour count you can trust is your own, invest in new tubes and reset number, maybe note the old count for a total hours of use record.
My sather had some noise on his and as he bought a dealer demo (saved over 3K) AR sent new tubes for free.
I have owned a Ref 3 for a couple of years. The lifespan estimates made by ARC for all tubes as applied in this device are extremely optimistic. The 6550C shows some sag at 900 hrs and usually needs to be replaced by 1100. In my unit the driver tubes had lost their bounce by 1700 hrs. I have tried a couple of different tube variants, but prefer the transparency/clarity/linearity/detail of 6550C and 6H30s supplied by ARC. You will find a good discussion on 6550C alternatives here:

Before any serious evaluation of your Ref 3, give it fresh tubes and break them in for 100 hrs or so.

I've owned the LS16, LS25, ref 2 and Ref 3...the LS 25 was more musical than any of the other offerings. The 6H50 tube was the last nail in the coffin for ARC...might as well be solid state (not very good SS either). That said, the Ref3 can sound amazing with fresh tubes, a great power cord and musical ancillary equipment.
Yeah, something must be wrong. I moved to the Ref3 from the Ref2 mk2 and the difference was astounding. As Guidocorona said above, get some new tubes before you rush to judgement.

The Ref3 is a monster.

Be sure and report back to us your findings after re-tubing and burn-in.
Mitch what is the difference in sound between the Mark 2 and the Ref 3. If the sound becomes leaner, more dynamic and quieter, I am not interested. The mark 2 is lean enough.
Yes, Ref 3 is much more dynamic and quieter than LS25 Mk2. The old ARC silver-gray sheen is gone completely. The sound is very focused, has loads more authority, and harmonic complexity than LS25 Mk.2. . . . but it is not at all leaner. On the other hand, Ref 3 is in general not an idiosyncratically 'tuby' sounding linestage. . . it is rather linear instead, at least for a tubed device. If anyone were interested in giving their Ref 3 a golden glow, try to put a new production Tungsol 6550 in the power supply. I personally prefer the linearity of the factory supplied SED Winged 6550C. G.
Dear all,
Many thanks for your answers
I bought My REF 3 used, and it runs 6L6GC tube in power supply (my REF 3 is from 2005). I will order a new full set of tubes and try new tubes, i will also do the upgrade with 6550c tube and the 4 bypass caps asap. I've opened my REF 3 yesterday and tubes look original ones (the 6L6GC is on bad condition and it's difficult to read what is written on the tube), i guess my REF 3 tubes has more hours than what the counter is saying. I saw also that resetting the hours counter is very easy, so it has been maybe done by a previous owner. For the counter hours, i did some short listening sessions (less than 1 hour each) and i have been surprised to see the counter staying at the same number of hours and only increased for full hours listening (i need to say that my system is physically unplugged from power voltage when it is not used)
Best Regards
PS : Is TheTubeStore a good source for REF 3 tubes, as long as ARC doesn't want to ship item in France, and i will not travel to the US before Sep08 the sooner
Jwm,.......the Ref3 is not leaner. Guidocorona's explanation says it all.

The Ref2 Mk2 is a great preamp by any standard, and the Ref3 totally eclipsed it.
Hello ARCL60 , I 'm also a proud owner of the REF3 , I left the 6550C original supplied , but replaced the normal tubes by the DR version . I liked this roll out . The tubes were bought at the Tubestore , fast delivery , had no problem .Do you do the upgrade of the 4 bypasscaps your self ? In the Netherlands the importer refuses to do the upgrade for me , so I like to do it myself , but dont know
the value of the caps , and the place in the machine .Perhaps you have the schematics ?
Greetings Hans
Hi Hans,
Guido told me that the 4 bypass caps parts is around $80 at Audio Research. I will order the kit from Audio Research and ask for the schematic also. I know a technician who is able to do it in France, i will not do myself. Do you know why the Netherlands importer doesn't want to do it ? That's strange the France importer should be able to do it i guess, but i prefer to work with my Audio Research Authorized technician who is closer to me. I ordered a set of tubes from TheTubeStore, and i will order the kit of bypass caps when i will travel to the US, so i will have the caps installed with 6550c tube a little bit later.
I will let you know for the bypass upgrade
Hans, the bypass caps installation is apparently a simple matter that can be done by any technician. ARC supplies instructions/schematics with the caps. Best to contact ARC directly and speak to Leonard. Guido
Mithc Guidocorona compared the Ref 3 to the Ls25mark 2, not the Ref 2 Mark 2. The Ref 2 mark 2 is a much better sounding preamp than the LS 22.
Hello arc160 , the Dutch importer told me only that the 4 bypass caps will not make my REF 3 better .So I 'am very interested what will be the result in your amp.Please keep me updated when you have let them installed.
Regards Hans
The Netherlands
Arcl60 - you should go an extra mile and get NOS TungSol Black Plate 6550 tube. The improvement is not trivial, and much, much greater than what can be acheived by putting DR tubes (I have both DRs and NOS 6550 in my Ref 3).

We discussed it over here:

ARC Ref 3: Tung-Sol 6550 in power supply?
Hi Reference 3 Owners,
I replaced the tubes from my reference 3 with Sovtek 6H30 (matched tubes) and 6L6GC from SED.
The overall performance improved, but i was not fully satisfied, then i re checked my full system in term of cabling and speaker connection, then i discovered that my pair of JBL 2405 tweeters were not connected properly (they were not on phase : the + plug was on - cable and the - plug on + cable). I guess i did some tests in the past when my LS25MKII get sold and i think i tried several things to improve the performance of my spare preamp an Audia flight Pre to improve it at LS25MKII level without success !!!, it was just a bad thing !
So now the image is much much better, i'm satisfied with the overall result and i found the Reference 3 totally different in term of 3D image than the LS25MKII. The LS25MKII is providing a flat image in comparison with the Reference 3 with really gives a 3D image with a lot of space all around the instruments and voice. In comparison with LS25MKII the voices seem a little bit behind, so i need to be familiar with that new sound image. It maybe required more time on the tubes to get the voice as they were with the LS25MKII.
I checked inside my Reference 3 and the bypass capacitor are in place if i well understood where they are located (just behind the 4 golden capacitors), so i don't need to get some from Audio Research.
For the 6550 tube in place of 6L6GC can i just remove the 6L6GC and put a 6550 tube on the power supply stage ?
If yes, i will do the try with a new Sveltana 6550c i have in spare, and i will order a Tung-Sol 6550 Black plate as suggested by Elberoth2
So if you can confirm me for the 6550 tube it will be nice
While I am looking for a new pre amp...and have considered the ARC Ref 3...I have heard that there have been a number of revisions to the unit...changes...given ARC's history that should be expected...has anyone document any changes.??? if they actually exist

As I understand there are at least 2 iterations of the original REF 3.If you are considering purchasing used that would be a fair question to ask.
According to ARCDB.WS, only 1 revision was ever made to Ref 3, and this was about 6 months after release. . . the 6G6 in the power supply was replaced by the SED 6550C, and 4 bypass caps were added. . . the bypass caps were apparently planned since day 1, but were not available from the supplier at first customer ship date. See:
Could someone please confirm that the 6L6GC can be changed by a 6550c with no risk. I guess i should the 4 by pass capacitor on directly on the back of the board where the 4 golden caps are located (0.024 µF cap i guess)
Thanks in advance
PS : i'm starting to be extremely happy since news tubes are into my Ref3 !
Hi Audiogon's Members,
I changed the tubes on Ref3 and it really starting to be much better in term of definition. My tubes should have around 20 Hours, so i guess it will improve again.
I'm very impressed by the 3D image of the preamp which for example place the voice at the right depth vs my old LS25MKII which provided a less deeper image.
What will be the benefit to put a 6550C in place of 6L6GC ?
Is the difference very import in term of image and definition ?
Best Regards
Laurent, I do not have direct experience with 6L6GC. . . however, according to ARC, the SED 6550C is supposed to yield greater extension, linearity, and authority than 6L6GC. G.
Hello Arc160 , yes you can change the 6L6 by the 6550C.The 4 bypasscaps are on the back of the board where the 4 golden caps are located.The bypasscaps ( 0,0024 mF ) are C111-114 , don 't mount them on the board , but leave some distance ( about 5 mm ) to the board.
Greatings from the Netherlands Hans
Hi Hans,
Many thanks for the confirmation, i will do the test.
For the ByPass capacitors, i checked my Ref3, and they are there
Best Regards
Hello ACR REF 3 owners , I replaced the original 6550 tube
by an NOS Tung-Sol 6L6 WGB , I will tell you after some 100 hours what will be the differance .( together with the 6H30P-DR tubes some 200 hours ago )
Greetings from the Netherlands Hans
Hi All,
I had the chance to re listen the LS25MKII on my system directly front to front with my Ref3. So i confirm that Ref3 is on another league than the LS25MKII. The Ref3 sound more natural, with more details and it's 3D image is amazing.
New tubes, power cable and patience improved a lot the performance of the Ref3. I noticed also that removing the silicon rings on the 6H30 has improved the quality as well
Thanks again to all Audiogon members for their answers
I'm an happy Ref3 user now
I have found that it is best to follow what Audio Research says when it comes to the right tubes . Call them and ask to talk to a technician. They will recommend the right tubes from audio research.
Dear Brothers,

I am Michael from Hong Kong. I bought my Audio Research Reference 3 Preamp from the previous authorized Hong Kong dealer in 2008. Now I intended to upgrade the said 4 pcs 0.0024 coupling caps inside the Ref3 but the present authorized Hong Kong dealer refused to help me to make such order.

Would you guys offer me assistance to that? Of course, I must pay you back the charges in advance, if any.

Thanks for your help.

Michael Cheung
from Hong Kong
Michl, you need to contact Audio Research directly. Here is the ARC page on Audiogon:
Dear Guidocorona,

I contacted them already by overseas phone call but they asked me to contact the local dealer direct and they do not deal with end consumer!!

Oh my god!! What can I do? Would anyone offer me any help?
Thousand thanks.