How do you know when it is time for new tubes?

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Bill Stevenson
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How do you know when it is time for new tubes?

Post by Bill Stevenson »

My cj equipment still sounds good, but the hours are now over 2000. Should I just wait, or what? ET5, ARTsa, TEA2MAX.
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Re: How do you know when it is time for new tubes?

Post by Big Dog RJ »

G'day Bill,

new tubes are in order generally based on the following:
1. Preamps: you will notice a dull sound, very low level rumble, extended noise floor and no life or kick in the level control (very noticeable). Generally with preamps since they are smaller tubes, can be replaced after around 4-5 years of usage. 3 years would be ideal but they can last much longer.

2. Power Amps: the smaller input and driver tubes would also last for around 4-5 years, sometimes longer, depending on actual usage. Again, replacing every 3 years would be ideal. The main thing with power amps are the output tubes. Since these are power bean pentodes, they will deteriorate within a specified period, sometimes 3-4 years, sometimes sooner. Ideal replacement would be around the three year mark just to keep everything in top condition. I generally change all tubes every 3 years, and use some good ones as spares just in case. Once the new tubes arrive, I would send off the older ones to people who collect these, there are a few chaps who look for older used tubes since they have more life in them.

3. With the Tea2max: again these are smaller input tubes, would definitely last well over 4-5 years. You could so a change around the 3-4 year mark, that's upto you and your expenses.

In summary: the general rule for larger output tubes is to replace them every 3-4 years of "normal usage." That means the amplifiers are always switched off when not in use and powered up for a short while (2-3 mins more than adequate) before listening. It is not necessary to warm up tubes for hours or extended times- this is a myth in the past... Tubes take only 3-4 mins to go well, and after listening is done, shutting down immediately will obviously extend tube life.
Smaller tubes can go on forever, sometimes way past 5-6 years, again depending on usage and how the preamps and other gear interacts with the tube.
I have had chaps tell me that their ET5 and GAT goes through tubes too quickly, this is because of not proper matching initially. Just because the amp is brand new doesn't mean that the tubes are good to go for another 3-4 years.Tubes can go off even during transit and especially travel, they don't like to travel and can fall "sick" in the interim. All depends how carefully they have been handled. The general norm is to have a few spares on hand just in case. Keep an eye on the output tubes, they are the main ones to look out for.
hope this helps, cheers,
RJ
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Re: How do you know when it is time for new tubes?

Post by plurn »

Hi RJ,

Can you clarify what you mean by "this is because of not proper matching initially"?

Thanks,
Anthony
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Re: How do you know when it is time for new tubes?

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Hey Anthony, yes thought I might get asked that question.
When I was using several cj preamps over the years, pv8, pv10, pv12, premier 16LS, premier 17LS, classicSE and now the Act2 series2, I noticed that tube hiss and life of tube varied so drastically. Unlike output tubes, cj goes through a burn in process and then matches output tubes in batches closely related to their output voltage, cj did not do this stringent control on smaller tubes. The output tubes were an important part of the power amp, therefore cj took extra care in "matching" such tubes. A very similar process was followed by VTL, Manley and ARC. Not so sure about McIntosh. The process involved takes a considerable amount of time, at the end it is also reliability that counts.

No two output tubes are the same. Each output tube burns in differently and deteriorates at their own accord. However, to sound right initially, they can be matched to close parameters within a batch or set of matched pairs, giving you a slightly better reliable factor.

Getting back to the smaller input and driver tubes mostly triodes, these are not initially matched therefore will have differences across their lifespan. Excessive tube rush mostly on one channel, tube degradation faster than usual, and noisy tubes. You actually can find matched pairs of these small tubes, and when fitted you will notice that they are quieter. They also cost more than most "standard" replacement sets.

Cj, VTL, ARC and similar companies tend to focus more on their output tubes because they know when the 2000 hr mark is up, "most" people will order a full replacement set for their amps. This covers all previous tube problems such as hiss and noise and the customer thinks replacing all tubes was a brilliant idea! Not necessary...

This is also why other names such Ayon, CAT and Lamm are very expensive because they follow a very stringent quality process on all their tubes; from input to output they make sure they are providing the best sound as consistently as possible, hence they come at a price.

If cj and the others were to follow this quality control on small tubes, you will find the price tag of an Art amp to start at around 50 grand upwards, forget anything below 20 grand. ., at the end that's what you pay for.
I have used Cj, ARC and VTL in my systems and all of them have pretty much the same philosophy, and that is to source reliable tube brands, which helps in their sales.

Lamm, Ayon and CAT take this obsession to another level, which is not something I can afford but I can tell you that their amps are extremely reliable, it is like owning a fine piece of jewelry. They leave absolutely no margin for error and when you listen to a Lamm you will know exactly what I mean. It better be at 130 grand for a pair of monoblocks!
Have a good one, RJ
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Re: How do you know when it is time for new tubes?

Post by plurn »

Hi RJ,

Thanks for the clarification. I guess I would consider this as "tube testing" rather than "matching" but they are both similar I guess. In the ET5 there is just one tube so matching would be for the two triodes in the tube, unless you mean the tube needs to be matched to the ET5.

I have heard and proposed other reasons for the GAT and ET5 being hard on tubes, but I am getting too off topic. There is a whole thread on this hard on tubes topic on another site so no point getting into it further here. Also for balance, there are a number of people who say these devices are not hard on tubes.

Getting back on topic, there is this from Conrad Johnson:
Q. How long do tubes last?
A. That varies depending on the type of tube, the number of hours of use and the type of use they have had. Typically tubes should last, on average, about 1500 hours before gradual degradation of performance becomes noticeable. This translates into two to three years if the unit is turned off when not in use. Usually tubes will continue to be functional for a long while after this, but sound quality will be reduced and noise levels will increase. In power amplifiers, the input tubes are most critical for sonic performance. If output tubes are not causing problems, they can be replaced every other time.
http://www.conradjohnson.com/It_just_so ... cjfaq.html

Also I have read that it can be a good idea to keep a spare set of tubes around, so that if you suspect that your tubes are getting tired, you can swap in your spare set and compare. If they sound the same then your old tubes are still good and you can swap back.

You would want to limit how often you do this, and be careful with the tubes to avoid damaging them by rough handling.

Anthony
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Re: How do you know when it is time for new tubes?

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Hey mate, yes spot on that. In fact that is what cj and a host of others say. Keeping spares and replacing every 3-4 years will keep everything in top condition. At the end, it also depends on the person's finances, if you can continously afford to change might as, plus the more tubes in the system the cost goes up. This is the one biggest reason I decided to end up the simpler route. With just the one power amp and preamp, total number of tubes required replacements would be 11 and this can be done in stages.

Yes, agreed with the Gat and ET5, they do burn tubes rather quicker compared to most competitors. This is mainly because their parameters are set quite high: high current, high voltage, high levels of capacitance and so on, therefore the tubes are operating at their "optimal" best. That's why they sound so good.

The ET5 has only one tube so does the ET3SE. I would think that since it's just the one tube, matching and testing would be easy. However, you do get the odd one now and then. A fellow mate has the ET5 and there is significant tube hiss on the left channel. He has the same Quad stat that I have and is using the ARTsa. He ordered a spare from cj and it was quiet for a short while until the hiss came on again after a few hours. He then ordered the tubes from psvane at nearly double the cost but with no hiss/noise or any issues whatsoever. Been working fine since last Aug 2015.

I order most of my tubes from cj directly with a special note to the service dept stating "gold pins please!" I was told by Lew that these gold pins are hand selected and tested for anomalies before shipping, hence carry a small surcharge. Whether it's worth the extra spend or not, I can't really tell but one thing I can confirm is they are a bit more reliable.

Does cj do a series2 on the ET5? They now offer a S2 on the Gat, I have listened to it but I'm still not sure if the extra spend of 4 grand is justified.
Cheers, RJ
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Re: How do you know when it is time for new tubes?

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Thank you for taking so much time to answer my seemingly simple question. I typically turn my system on in the morning and it goes all day, every day. 12 hours or so total every day. It all sounds just fine, no noise, no deterioration that I can detect. I do have a spare set of tubes and never thought of plugging them in just to verify that all is well. Maybe I'll give that a go this weekend. Two additional factors may affect tube life: 1. how hard the amp is working, and 2. the use of cooling such as central air and/or small fans for electronics.
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Re: How do you know when it is time for new tubes?

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Ok Bill, no wonder you've reached the 2000hr mark!

Just a quick question, why is the system powered up for that long? Are you actually listening for all those hours? If so, that's great! Looks like you've got ample time to listen which is a luxury for my life.

If not; then this is a complete waste of tube life.

Powering up the system only half hr before is ample time to warm up everything nicely. Overall, the system will only sound better when music is actually played, not whiles ideling. Lew himself confirmed this many decades ago. Trust your system is not ideling. ..
Have a good one, RJ
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Re: How do you know when it is time for new tubes?

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Hi RJ,

Using mostly a Sony HAP-Z1ES as a source, my system is on and playing music all day. When not traveling, I work out of my home office, so while I am not listening critically all day, the music is in the background. When I hear something I like, my whole attention transfers to the music. At lunch I listen with full attention. At the end of the work day the system is switched off for an hour so I can watch the news on the telly. Then after dinner the system goes back on for serious listening, most often using vinyl as a source, for perhaps 2 or 3 hours more. Altogether about 12 hours a day with the system on.

Regards,

Bill
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Re: How do you know when it is time for new tubes?

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Now I understand, fair enough.
Looks like the system is receiving a superb overall warm up before you indulge in some awesome vinyl. Excellent!

Was just wondering, what TT do you have? Cartridge etc.
What are the sonic attribures of your cj phono stage?
How did you decide upon the Tea2max? After comparing with other phono stages.

At one point I was thinking about this very same phono stage but thought I'd wait out a bit and check out a few other names just to add to the mix. Extremely difficult for me to decide on phono stages, all sound really good to me. For now I'm using a very simple Rega with the upgraded Rega power supply. I did try out a few phonostages well over the price of the Rega, and many of them fell short. The only ones that really made a difference that were quite remarkable were the cj & Arc phonostages. The others were either too expensive for my budget, couldn't justify the cost.

Interesting stuff indeed.
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Re: How do you know when it is time for new tubes?

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Turntables. I should back up and explain that I own 5, use 2 regularly. Let me comment on the two in regular use. They are a VPI Prime that is all optioned to the hilt. It has an HRX pulley with double belts because of the added mass of the platter due to the use of the VPI periphery ring. It also is powered via Phoenix Engineering's Roadrunner tachometer and Eagle PSU with the tach providing feedback to the PSU to ensure accurate and consistent speed. The cartridge is an Ortofon Cadenza Black most of the time, which is a LOMC. I own two alternative cartridges, an Ortofon 2M Black and an Audio Technica AT150ANV, both MM. I could be happy with any of these, but the Cadenza Black is the best of this group. This turntable represents a very high grade sound source. Very near to as good as any. It is kind of a clunky thing, though, and requires a great deal of patience in setup and operation. The other turntable is a Technics SL1200MK2 with full KAB mods. It is my mono turntable most of the time and has an Audio Technica AT33Mono Anniversary. In terms of performance it easily matches the VPI in speed accuracy and consistency (wow&flutter), but comes up a bit short mostly because of the arm I believe. An SME tonearm would do nicely and bring it right up to snuff no doubt. I am hesitating because there is a new replacement audiophile turntable from Technics due out this summer and I want to see about it first. Also, the ergonomics of the SL1200 are peerless, it is a dream to set up and to change cartridges and that is an important factor for me. An SME tonearm might sound better, but be less satisfactory for ergonomic reasons. Mind you the difference in sound between these two turntables is best described as only a wee bit.

In terms of phonostages, trying to make heads or tails out of this subject for the average audiophile is about as difficult as choosing mono phono cartridges. Good luck finding any to listen to at a store. And these days good luck finding an audio store that really knows the ins and outs of playing vinyl. I also have a couple of other phono stages, the best other being a Creek, which is quite fiddly what with dip switches and whatnot, but it does sound good. Manley makes nice phonostages, too. If you can find one, their Steelhead is quite worthy. But I agree with you that cj and ARC are both really the best I have experienced. What I like about the TEA2MAX most of all is that I can plug in a 5.0 mV MM cartridge or a 0.3 mV LOMC and it can handle such a wide signal range without needing to adjust anything. Wonderful. I might be listening to a modern recording by Wynton Marsailis and want to compare it to the same tune recorded in 1935 by Louis Armstrong and now you know why I use two turntables. Anyway, the TEA2MAX requires no changes, no dip switches, nothing. Just plug and play. Oh it has a sound that is absolutely magic too, and it is quiet, no noise whatsoever. Clearly it is not cheap, but there are many that cost a lot more with no clear advantages over it. Tubes flatter vinyl in my opinion and I would choose one with good write-ups sold by a vendor you trust. It seems you have a full understanding of what is out there. Frankly when I buy these things (i.e. both cartridges and phono-preamps) doing so requires a full leap of faith.
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Re: How do you know when it is time for new tubes?

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G'day Bill, a lot to learn from that post, excellent insight, thanks mate.
No, I am no expert at all nor do I know it all. It's just that I've been through a very interesting journey, having lived in various countries across different regions and have experienced so many systems, that I can claim are either "true value" or rightoff rip offs... cj is definitely in the category of superb value regardless of price.

Yes, whenever I do get the chance to listen to the Tea2max, there is definitely some magic going on through vinyl no matter what TT. The beauty of analog, unlike digital, you can improve on just by the stylus or cartridge, and the whole rig gets even better. Digital, wel it's digital. Not too sure where it would go from there. ..

Enjoy and have a good one! Cheers, RJ
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Re: How do you know when it is time for new tubes?

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Big Dog RJ wrote:<SNIP>The beauty of analog, unlike digital, you can improve on just by the stylus or cartridge, and the whole rig gets even better. Digital, wel it's digital. Not too sure where it would go from there. ..
Hi RJ,

I respectfully disagree. Digital components, just like any other types, are responsive to interconnects, power cords, etc. and the user may tailor the unit's sound accordingly. Just my 2¢ naturally.

Regards,
Joe
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Re: How do you know when it is time for new tubes?

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I listen to both digital and analog, including a McIntosh Tuner and think you both make valid points. Digital at it's best is sonically superior and a whole lot less fussy to dial in. On the other hand, downloading a HiRez file just lacks the tactile experience that vinyl provides. And of course vinyl requires effort in selection, adjustment and getting up to flip records, cleaning and so on. God help me I love it all.
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Re: How do you know when it is time for new tubes?

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G'day Joe, good to hear from you mate.
How's that ca200 coming along? Trust you're getting some musical tunes!

Yes mate, totally agree on the digital, infact I still find it more accurate or focused so to speak. Gave up LP's back in 98, headed back to homeland from Chicago. Good old days experimenting with top dacs from meridian, aragon and meitner at the time. Had various systems, on the speaker front it was ribbons to large dynamic drivers etc. Fast fwd to 2016 and now living in a different country, I had to give up my previous systems and start from scratch.
Used digital from 2005 to 2015, until venturing back to lp's slowly, starting with a Rega RP3 & 2m black. The thing is after acquiring the Quad 2905's partnered with the Act2 and classic60se, I just find vinyl to be even more relaxing, although the pops & clicks arw really annoying. There is something more of that extra expansive soundstage that I find with my current c-j amplification through stats listening to lp's. I don't know what it is, perhaps extra surface noise distortion whatever. The other thing is the digital sacd source that I'm using is nearly 3 times more the price of the simple Rega. Perhaps my sacd rig is not that great, although I absolutely love it. For that real laid back expansive soundstage, I find the Rega and its matching phono stage to be a treat to listen to. I was thinking of upgrading one of these down the line to perhaps a michell gyrodec or a top line dac and separate transport but why bother.
Since, I am enjoying both formats, and have grown a fondness towards one type of source more over the other, at this stage I am going to just sit back and enjoy the music!

I am quite keen though to see where digital would go from here, although it's a fact that vinyl sales is on the rise and the newer generation is actually starting to like it. Maybe the newer generation is not aware of top quality digital playback systems, and they do cost a fair lot more compared to a simple analog rig.
I am venturing into my favorite analog dealership this weekend to take a spin on a top line gyrodec through some top line ARC gear through SF Strads, just for fun. I want to discover and learn something new, we're later going to use the top of the line digital playback from ARC, I believe the cd Ref9, interesting to hear the sonic attributes. Till then enjoy the music and have a good one. Cheers, RJ
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Re: How do you know when it is time for new tubes?

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Hi RJ,

The CA200 is doing fine except for a nasty habit of blowing the mains fuse at a cold start-up or sometimes going from standby to active. The only solution I've found is to leave it powered-up all the time. Could be the after market fuses I use don't have the upside tolerance that the stock fuse has but the difference in sound with the aftermarket fuses make it worthwhile.

I had a Clearaudio Concept turntable with a 2M Black myself for a while. It hadn't been set-up properly by the dealer and no matter what I tried, couldn't get it to work properly on a consistent basis. But when the sun, moon and stars did align properly I know what you mean about the soundstage. Sold it to someone who knew what he was doing and since I never heard back from him (other than his saying that the set-up wasn't right), I assume he's happy with it.

Regards,
Joe
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