CJ ART sa / 8 or 4 ohm

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rsm
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CJ ART sa / 8 or 4 ohm

Post by rsm »

Hi

I will be getting an ART sa amp soon. I have an ET5 and HD3 dac fed from laptop running j river 18. The ART sa will be driving Avalon Transcedents. My friend and CJ dealer of many years is adamant that I should order the ART in 8 ohm configuration and not 4 ohms, despite the Transcendents being nominally 4 ohms. A while ago I read a review of the Prem 140s where there were some comments from CJ themselves explaining why the 4 ohm version was better than the 8 ohm......something to do with maximum utilisation of the output transformer windings? Can anyone out there give me solid advice as to which output version to order? Much appreciated, RSM
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Re: CJ ART sa / 8 or 4 ohm

Post by eagle6014 »

Well I just read the specs of your speakers on the Avalon Acoustics web site and from what I see, I would stick with the 4 ohm. I honestly don't know if going w/ an 8 ohm ARTsa would make any difference since it's so powerful. But internally there has to be a way to change the output taps by the consumer so you can do a/b comparisons. It does say on the web site your speakers are 4 ohm nominal & not 4 ohm minimum so I guess the amp would do just as well in 8 ohm. I'm super jealous your getting an ARTsa b/c that's what I want. I'm not far from getting an ET5. Hopefully at the end of the yr. How's that c-j HD3? I've been eye ballin' that as well. Any trouble in getting your computer set up w/ that? And are you using the Windows media player? Pat
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Re: CJ ART sa / 8 or 4 ohm

Post by rsm »

Hi Pat
Thanks for your input. The HD3 appears to be very good. However, I have not had a chance to compare it to anything else, as I changed my entire system a year ago. What I can tell you, is that it takes weeks, if not months, of trial and error to get the dac working without glitches with j river 17 or 18 using windows 7 ie. bypassing windows media player entirely. . Apparently windows 8 is slightly less bright with j river.I am now at the stage where I get no errors at all, using an i5 2450 processor. Rob
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Re: CJ ART sa / 8 or 4 ohm

Post by admin »

Interesting, I thought that the actual computer used should have no effect on the audio output from the HD3 as the audio is bitsreamed to the HD3 and then converted to analog after that. Also, the usb interface should eliminate all jitter from the signal as well. Is this not correct?
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Re: CJ ART sa / 8 or 4 ohm

Post by rsm »

Hi,
As with all digital audio, things are not simple........you would think that one laptop/processor/OS would sound like another! My older i3 with windows 7 home edition using the exact same settings in J River sounds completely different to the i5 with windows 7 pro! In actual fact, the older, slower i3 was way less bright and marginally less detailed. I also discovered that the i5 sounds way better with the battery removed and just powered by the laptop PS. Go figure!? Then there is the age-old question of cabling........USB cabling................It's a mine-field out there! I wonder if you couldn't have a look at my query re Art Sa amp/ impedance. I need to make a decision re 4 or 8 ohm configuration. Perhaps you know way more than I do about it? Thx, Rob
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Re: CJ ART sa / 8 or 4 ohm

Post by Ray »

rsm wrote:Hi,
As with all digital audio, things are not simple........you would think that one laptop/processor/OS would sound like another! My older i3 with windows 7 home edition using the exact same settings in J River sounds completely different to the i5 with windows 7 pro! In actual fact, the older, slower i3 was way less bright and marginally less detailed. I also discovered that the i5 sounds way better with the battery removed and just powered by the laptop PS. Go figure!? Then there is the age-old question of cabling........USB cabling................It's a mine-field out there! I wonder if you couldn't have a look at my query re Art Sa amp/ impedance. I need to make a decision re 4 or 8 ohm configuration. Perhaps you know way more than I do about it? Thx, Rob
Interesting comments! thanks! I must say that in my experience, I've not been able to detect any differences. My experience with JRiver began with Version 16 of MC and originally on Intel Atom based motherboards...a few years and many builds later, I'm now using a few different Asus motherboards and a host of CPUs from i3 2130 up to a i73770s, my desktop install of JRiver is a i73960X (although the DAC hookup/speakers on the desktop is not the same as what I use in the dedicated listening system)

Try as I might, I've been hard pressed to determine any "listenable" differences. (I don't use ANY DSP in JRiver, no resampling, and I'm exclusively Async USB to the DACs.) :geek:
I know this is often a hotly discussed issue in audiophile circles..and no doubt will continue.

More recently I've re-visited the WAV vs FLAC vs ALAC issue. All "bit-perfect", but apparently sounding different. I've done quite a bit of comparison on many occasions...I've got a few dozen lingering duplicated FLAC/WAV tracks to prove it :D In all my UN-scientific testing, I've never been able to conclude any difference.

I recently sold my old friend and first "major" DAC, the W4S DAC-2, replaced it with an Esoteric D-07X. (same hookup, Async USB to JRiver) I was actually quite amazed at the difference in sound character between these two DACs. I should also qualify this a bit as, a casual listener would be extremely hard pressed to identify one over the other, however, in the wacky world of high-end audio, where miniscule differences are described as earth shattering, in this case the differences are at least near earth shattering. :D ..but I very much liked the W4S and still do, and I very much like the D-07X also. :D
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Re: CJ ART sa / 8 or 4 ohm

Post by admin »

I myself have never been able to tell the difference between different lossless encodes of the same audio track. The DAC obviously will have a significant effect, but as for the identical source material in different formats has not made any observable difference in my system. Most of these comparisons have been from playing the original CD directly in the computer, encodes to FLAC, and encodes to WAV.
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Re: CJ ART sa / 8 or 4 ohm

Post by rthomeint »

I use a Mac Mini on my HD3 with pure music I tried jriver on my Viao Laptop I like the sound from my mac better. I also use an Audioquest carbon usb cable and a forrest firewire cable they make a difference. I recently add ici usb power supply, it's a nice sonic upgrade.

As far a 8 ohms or 4. I would go with 8 I have alway like the sound from the high ohm setting. My Premier 11 is at 16 ohms and the MV-50 and 52 I had both ran at 16 ohms. My dealer believes in this and I tried it and like the sound better than the 8 or 4 ohm taps. Granted it is a lot easier to experiment on the older amps.
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Re: CJ ART sa / 8 or 4 ohm

Post by joeinid »

Hi RSM,

I find myself in a similar situation. Did you ever get the amp wired for 16, 8 or 4 ohms. I am thinking about the ART monos and seeing this thread makes me wonder what to do. Any help will be much appreciated.
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Re: CJ ART sa / 8 or 4 ohm

Post by rsm »

Hi Joeinid, Sorry for late reply. My 8 ohm ARTsa has packed up after 5 months and 900 hours. Awaiting help! Did you buy the monos?
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Re: CJ ART sa / 8 or 4 ohm

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rsm wrote:Hi Joeinid, Sorry for late reply. My 8 ohm ARTsa has packed up after 5 months and 900 hours. Awaiting help! Did you buy the monos?
I did indeed.

viewtopic.php?f=6&t=357

They are amazing. Rayoo bought a pair after he found out how much I love mine.

Mine are wired for 4 ohms.

I am not sure I understand, do you still have the ARTsa or is it in storage.
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Re: CJ ART sa / 8 or 4 ohm

Post by rsm »

Hi. No no........ British English.......packed up equates to broken down! Loud crack followed by thump several minutes later. Smell of burning. Low distorted sound, replaced driver tubes but no difference. Tubes ok. No blown plate fuses. Waiting impatiently for response from CJ as to what to do. I am very disappointed. Was starting to sound good after 900 hours........
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Re: CJ ART sa / 8 or 4 ohm

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rsm wrote:Hi. No no........ British English.......packed up equates to broken down! Loud crack followed by thump several minutes later. Smell of burning. Low distorted sound, replaced driver tubes but no difference. Tubes ok. No blown plate fuses. Waiting impatiently for response from CJ as to what to do. I am very disappointed. Was starting to sound good after 900 hours........
Ah crap, sorry to hear this, hopefully not too awfully serious...although it's hard to imagine a scenario where a burning smell is NOT a serious issue.

A couple of Murphy's laws: a component always "burns open" to protect the fuse.. If the failure of any several components will protect the fuse, the component that costs most will be the one that fails.

Nice to have at least some absolutes in life. Or is that It's nice to have some Absolut in life? :)
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Re: CJ ART sa / 8 or 4 ohm

Post by Ray »

This is karma at it's finest, I make a comment about Murphy's law yesterday...and today, while listening in "Stereo" the system went to Mono.

Glancing down at the left channel ART..one of the output tubes was glowing nearly cherry red.
Replaced with spare, checked fuse, same issue.
Replaced with 2nd spare, same issue. fuse still OK,
..and of course the only recourse is the return the unit to CJ for repair. ....it's all coming back to me now, the reason I avoided tube power amps for all these years.
The ARTs sound absolutely stunning... I sure hope this doesn't become a regular need, $200 shipping to VA via Fedx Ground. yeehaa. 'not sure what I'd do if I lived in CA or Europe.

I promise to never quote Murphy's laws again.
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Re: CJ ART sa / 8 or 4 ohm

Post by camusmuse »

Ray wrote:This is karma at it's finest, I make a comment about Murphy's law yesterday...and today, while listening in "Stereo" the system went to Mono.

Glancing down at the left channel ART..one of the output tubes was glowing nearly cherry red.
Replaced with spare, checked fuse, same issue.
Replaced with 2nd spare, same issue. fuse still OK,
..and of course the only recourse is the return the unit to CJ for repair. ....it's all coming back to me now, the reason I avoided tube power amps for all these years.
The ARTs sound absolutely stunning... I sure hope this doesn't become a regular need, $200 shipping to VA via Fedx Ground. yeehaa. 'not sure what I'd do if I lived in CA or Europe.

I promise to never quote Murphy's laws again.
Murphy's Law and electronics.....never a good combination. Yes tubes can be high maintenance, especially when that much shipping is involved. And that doesnt even include the repair. I can only imagine the frustration. Of course me being the frugalphile...I barely paid more for my MV-50 that you did for shipping, honestly not trying to dig, but play big pay big. I'm sure your system would of floored my best(current is still in production), so you certainly have my respect there. But back to the original post, Ive ALWAYS gone by with the more impedance the better. Planar speakers and the like the exception. JMO though. Good luck to you all with your repairs, I am still working on my mv50....slowly.....very slowly....lol. Have to take workshop down to make room for new home office. (and hopfully new job!!!).
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Re: CJ ART sa / 8 or 4 ohm

Post by rsm »

HI Ray
Yes, a stiff drink could help! I hope this is not an indication of things (smelly and burning) to come. Only trouble is I am in South Africa. No agent here, so I am liable for shipping back to US if CJ and a local tech cannot diagnose the problem, To courier to US from here about $2000 with insurance! I have owned several CJ valve products in the past, one failed and had to be returned to the US for replacement. I have the ET5 now which has been fault-free but very noisy (quiescent) compared to the Prem 16 I had previously. CJ claims the ET5 has more inherent noise! Sounds good though.......We are hoping that CJ comes up with a quick solution to the failed ARTsa and that a schematic exists. Good luck to you too. Pls let me know what the verdict is on yours........ All the best
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Re: CJ ART sa / 8 or 4 ohm

Post by camusmuse »

rsm wrote:HI Ray
Yes, a stiff drink could help! I hope this is not an indication of things (smelly and burning) to come. Only trouble is I am in South Africa. No agent here, so I am liable for shipping back to US if CJ and a local tech cannot diagnose the problem, To courier to US from here about $2000 with insurance! I have owned several CJ valve products in the past, one failed and had to be returned to the US for replacement. I have the ET5 now which has been fault-free but very noisy (quiescent) compared to the Prem 16 I had previously. CJ claims the ET5 has more inherent noise! Sounds good though.......We are hoping that CJ comes up with a quick solution to the failed ARTsa and that a schematic exists. Good luck to you too. Pls let me know what the verdict is on yours........ All the best
Sorry Im not Ray....but holy yeah a stiff drink..... I dont know if you have the ability, but I have found a trick for international shipping. And yes its a little....well.... If there are any American Soldiers there(arent they EVERYWHERE???), they can ship much, much cheaper. I received a set of wheels from Japan and shipping was less than $200. I know this option is not for everyone, or everything....but 2 grand for shipping? I would buy a new unit and sell the old on ebay. Talking to CJ....they are very good domestically, but I have no idea from S. Africa. Please if what I suggested is illegal, do not pursue it, but.....if you are willing to take the chance....TRIPLE box it.
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Re: CJ ART sa / 8 or 4 ohm

Post by camusmuse »

I wont edit the last, but it may be worth contacting Zed Audio. He is originally from S. Africa, and is the KING of high end CAR audio, but he knows more than most, and can repair anything. He made the OEM amps for SEVERAL US companies before they all went to the far east for "disposable" gear. Mr. Mantz, the owner is very accommodating.....never know, hate to slam CJ but the 2k for shipping, he might have a solution for.....just an idea.....
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Re: CJ ART sa / 8 or 4 ohm

Post by Ray »

The returned ART should arrive at CJ today (Friday) and of course CJ is closed on Fridays I believe.
I truly admire the company overall, managing to stay in business all these years is a clear indication of their business sense...on the other hand I still find myself not being all that warm and fuzzy with the long term prospects going forward of these AMPS and CJ overall.

With the initial broken tube out-of-the-box, and now this failure.... It hit me that the "cherry red tube" was the very tube socket that the broken tube belonged in. again, a hmmmmm. Was the amp tested with a "broken tube" that somehow damaged that specific tube location? or did the replacement tube somehow damage things? ..and now I've got 3 tubes that had the "cherry red" test. Are these tubes safe to use again? Are they damaged? Will they Damage the Amp if I try then. So far, all the answers to these questions start with: "probably", "Should be", "yea, most likely" which again doesn't give me a warm fuzzy feeling. Hopefully in a few months these episodes will be long forgotten. I also know that if something pops up again I'm going to seriously consider going back to SS power amps. :( :( Oh well, these are all "first world problems" for sure.
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Re: CJ ART sa / 8 or 4 ohm

Post by camusmuse »

Might wanna see if you can pickup a tube tester. With the amount spent on the gear, a tester is relatively inexpensive and will generally let you know exactly what condition your tubes are in...including remaining life span. Not to mention it can let you "match" your own sets if need be.
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