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beardog03
12-24-2006, 02:09 PM
I`m off work for the next 11 day`s WWaaaahhooooooooo !

every week-end I leave the Cary on and the longer it`s on, the better it sounds..

My question is..

How many hours in a week, and how long do tubes last ?

I know it`s a stupid question , but hey....

Consider the source...!!

:D

BlueMDPicker
12-24-2006, 02:34 PM
Merry Christmas, Robert!

It depends on the tube, but on average somewhere between 3,500 and 10,000 hours for small signal tubes and half that for power tubes.

beardog03
12-24-2006, 02:36 PM
Thanks Blue !

Merry Christmas to you also..!!

So Basically after about a year or so, they may start to get a little weak ?

dkg999
12-24-2006, 02:36 PM
Beardog - not a stupid question, at least I'm voting that way because I would like to know the answer also! I run my Rogue pre and Jolida CDP about 10 to 20 hours in a normal week, and sometimes just have them on for a CD or two. How long does the normal 12ax7 or 12au7 tube last? Is there a point in which they still work but should be replaced?

beardog03
12-24-2006, 02:43 PM
would it be worth getting a tube checker ?
In my infinate wisdom I know there must be such a thing !?!?!

BlueMDPicker
12-24-2006, 02:52 PM
Many tube data sheets, especially for JAN spec tubes, rate their design life. IMHO, your ears are the best tube checker unless you're dealing with tons of tubes.

reeltrouble1
12-24-2006, 04:41 PM
Bear,

After some experimentation with the sound of the rigs I have taken to turning them off during the week to save some tube life on my pre's. In my case I have found that after about 30 minutes of warm up the sonic's I want are there.

I have experienced a noticble difference in the sound of a piece when the tube is used up its usefull life.

+1 with Mikey, unless you sell tubes, or just have to know I would use the old ears.

RT1

amulford
12-24-2006, 05:08 PM
You don't need no checker, Dog...

candyliquor35m
12-24-2006, 05:20 PM
Dear Mr. Tubes Rule,

Okay then let's get down to brass tacks then. I have 1.2 TLs and have been advised to go with no less than 200 wpc. I went with 300 wpc. with the adcom 565s. Now "Mr. Tubes Rule" :D (and you are not the first I've asked this question) how does a 60 wpc tube amp match up to a 300wpc solid state amp. I know the technical differences between tubes and SS i.e. high voltage trigger valve vs. high current continuous but again I don't see how 200wpc and above will make the SRSs sing but 60 to 80 wpc is really all one can get out of a tube amp atleast without mortgaging their home.

Your opinion please. Or would you rather me start a new thread :eek: LOL :D

Someone recommended starting a new thread on this so maybe this is a more appropriate one.

I know nothing about audio except what my ears tell me so this is my observation. My 100 wpc Golden Tube SE-100 appears to have as much power as my Carver 375 wpc TFM-45. I didn't A/B them so just my observation. I even bi-amped my SRS's using another TFM-42 (sonically identical to the 45 but with led's instead of meters) and didn't seem to gain anything or sound any better. Don't get me wrong, the carver(s) made the srs's sing just as loud and impressive as the tube amp but now it's up to the individual whether they prefer the sound of tubes or ss.

I've only had to replace one tube and I couldn't hear anything wrong with it but when I was biasing, I couldn't get a reading on that tube so I switch places with it and another tube and the biasing problem followed the tube so I replaced it.

ND13
12-24-2006, 06:12 PM
Someone recommended starting a new thread on this so maybe this is a more appropriate one.

I know nothing about audio except what my ears tell me so this is my observation. My 100 wpc Golden Tube SE-100 appears to have as much power as my Carver 375 wpc TFM-45. I didn't A/B them so just my observation. I even bi-amped my SRS's using another TFM-42 (sonically identical to the 45 but with led's instead of meters) and didn't seem to gain anything or sound any better. Don't get me wrong, the carver(s) made the srs's sing just as loud and impressive as the tube amp but now it's up to the individual whether they prefer the sound of tubes or ss.

I've only had to replace one tube and I couldn't hear anything wrong with it but when I was biasing, I couldn't get a reading on that tube so I switch places with it and another tube and the biasing problem followed the tube so I replaced it.


I run my SRS 2s on a Jolida SJ-302A, which is rated at 50 wpc. I doubt that they ever receive more than 20 of those watts and they're louder than hell.

I run my LSI 9s on an Anthem AMP-1 that's only rated at 40 wpc. Again, they are very dynamic and probably have never received more than 25 of those watts.

There is a major difference between a tube watt and a sand watt, imho. I have two pretty decent SS amps(Parasound and AMC) to use as backups.

beardog03
12-24-2006, 06:34 PM
Thanks for all the responses fellas...

I have a long way to go , as my unit / tubes are still fairly new (between 150 -250 hrs), just thought I`d ask for future reference.

SCompRacer
12-25-2006, 02:29 AM
A tube tester would be nice if you had the extra dough for a good one and a place to store it. While there was a time I did, I don't buy occasional or seldom used tools anymore.

While it wasn't asked, I figured mentioning something about Cryo'd tubes (Cryogenic, the deep freeze) might be useful. Normanality and I have experienced early failures with Cryo'd Tung Sol 5687's in our pre amps. I spoke to the manufacturer of my pre amp and it sounds like we are not the only ones to experience these failures. Mine would cause a popping or snapping noise from the speaker at timed intervals. So unless someone can counter with positive experiences, I won't be buying any Cryo'd tubes in the future. It sounded like the manufacturer wouldn’t be offering Cryo’d tubes either.




I know nothing about audio except what my ears tell me so this is my observation. My 100 wpc Golden Tube SE-100 appears to have as much power as my Carver 375 wpc TFM-45.


I'll be the +3 here. I have no idea how to ideally compare high voltage tube watts with high current SS watts. My first tube amp was a 75 WPC McAlister that used horizontal output tubes. It sent a Rotel RB1090 and a Carver TFM-45 packing for bass output and sonics. It could play to insane ear bleeding SPL's. I had SRS2’s with modded crossovers at the time. As cl35m pointed out, tubes or SS is subjective to the listener.

To the tube amp guys, only way to know if you are clipping, provided that you are not experiencing obvious roll offs or drop outs with familiar material, is to check with an oscilloscope. Connect it to the speakers + and - and set it to a medium slow sweep. On a 60 WPC tube amp you would be looking at a peak power of 22VRMS. Play something demanding and adjust the gain to keep the image on the screen. Increase volume to see if or at what SPL clipping occurs.

One other thing is not all SS amps are high amperage. Sanders Sound Systems SS ESL amps (600WPC@ 4 Ohms) are high voltage instead of high amperage and it is an excellent sounding amp. Normanality uses one on his ESL speakers. It barely gets lukewarm playing all day, a big plus in a small room or an enclosed space. While I am extremely pleased with the performance and sonics my two TAD-60 tube amps provide, I can see a Sanders ESL amp in my future. The ESL Amp White Paper (http://www.sanderssoundsystems.com/ESL%20Amp%20White%20Paper.htm) if anyone is interested in reading about it.