Deleted
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Post by Deleted on May 13, 2015 15:53:43 GMT
Is there a rule of thumb as to whether valves burn-in? NOS in particular but new ones too.
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z3d
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Post by z3d on May 13, 2015 16:56:04 GMT
Hello, I'm burning mine for around 25hours just to have them settled; I think it's a correct number of hours but let's wait for some more expert thoughs  |
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Post by Deleted on May 13, 2015 17:25:02 GMT
Hello, I'm burning mine for around 25hours just to have them settled; I think it's a correct number of hours but let's wait for some more expert thoughs Yeah, I think there's almost certainly going to be an element of burn-in involved since it is actually burning, in a way. The problem is that differences between valves can be so subtle that brain burn-in is going to be an issue too. |
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Post by Deleted on May 13, 2015 19:27:21 GMT
Thanks for the input Mick. Like I said, it's quite possibly in my head. Its actually that valve you gave me. I liked it. Then I didn't. Now it's been in there for a week So much of music appreciation is down to your state of mind and yet people rarely talk about it. Gordon. |
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Crispy
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Madrigal music is playing - Voices can faintly be heard, "Please leave this patient undisturbed."
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Post by Crispy on May 13, 2015 21:30:40 GMT
I have been saying for years.. that how your feeling at a specific time of day has a direct influence on percieved SQ. I can switch on in the afternoon....listen to the same album as i did last evening...using exactly the same setup...and think...that`s not sounding as good as last night. In reality it must be sounding exactly the same on both occasions, but my perseption of it is not. Strange but true. Mick. Mick I have observed the same situation myself and not only think its the perceived sound but something to do also with the electricity companies turning the juice down when the demand is not so high? Frans may be able to throw some light on this? But I think when they turn the power down it affects your amps and they do not sound so good? Chris |
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Post by Deleted on May 13, 2015 21:51:01 GMT
I have been saying for years.. that how your feeling at a specific time of day has a direct influence on percieved SQ. I can switch on in the afternoon....listen to the same album as i did last evening...using exactly the same setup...and think...that`s not sounding as good as last night. In reality it must be sounding exactly the same on both occasions, but my perseption of it is not. Strange but true. Mick. Mick I have observed the same situation myself and not only think its the perceived sound but something to do also with the electricity companies turning the juice down when the demand is not so high? Frans may be able to throw some light on this? But I think when they turn the power down it affects your amps and they do not sound so good? Chris If you're trying to say don't put the kettle on then you're out of luck. I live on Earl Grey.  |
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Crispy
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Madrigal music is playing - Voices can faintly be heard, "Please leave this patient undisturbed."
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Post by Crispy on May 14, 2015 12:37:32 GMT
Chris If you're trying to say don't put the kettle on then you're out of luck. I live on Earl Grey. Gordon yeh tea affects your listening pleasure, better off drinking beer  I did a little research and came up with this interesting bit of info. Power demand in the electricity supply reduces the mains frequency as well as its voltage. As new customers are added the system gets overloaded and the voltage & frequency drops, especially at time of high demand like TV programme breaks and the effect of 20 million kettles being switched on at the same time has a big effect on the supply of electricity. The legal requirement is that mains frequency must be maintained at 50Hz over a 24 hour period. Suppliers are then able to increase the frequency at certain times to compensate for drops at other times. The frequency is commonly increased late at night. These fluctuations in mains frequency have an effect on a Hi-Fi system. Most turntables use A/C synchronous motors whose speed of rotation is locked to the mains frequency. A turntable with a synchronous motor plays slightly slow when the frequency drops at times of high demand and slightly fast when the frequency is higher at times of low demand (eg. late at night). When it plays slow, the music is slightly down in pitch and dull; when it plays fast the music is pitched higher and sounds fast and exciting. Lets see what Frans has to say - it may be very interesting?  |
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solderdude
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Post by solderdude on May 14, 2015 13:52:38 GMT
Chris is perfectly correct about the mains varying.
Logging it during the day shows frequency and voltage vary as well as waveform.
The sinewave is 'flattened' and thus has a higher amount (but still quite low) of harmonics when more current is drawn.
Turntables with synchonous motors (AC motors that use the mains frequency) are quite rare these days but still exist.
There are only a few of those around.
Most are quartz locked, have DC motors or motors that are have a feeback loop.
These all are independent of mains frequencies.
How many people have ever noticed their turntables to run slightly faster or slower (this is gradual)
Did you know that the average frequency of the mains is regulated so that when measured in 24 hours the frequency is exactly 50 (or 60) Hz.
They do this by purposely raising or lowering the frequency somewhat now and then.
The reason for that is that many mains fed mechanical alarmclocks (pre-X'tal age ?) will thus run accurately over a very long period.
All electronics that have CE markings on it must be able to handle voltage variations.
For the UK its 230 +10%/−6% (so 216V to 253V)
For Europe its 230 +/−10% (so 207V to 253V)
Nowadays most electronics have (wide range) SMPS which allows voltages from 100V to 250V while keeping the output voltage constant.
Equipment with mains transformers usually can dip below 207V without too much problems as regulators also have some 'headroom'.
Personally I have never seen equipment perform less with lower voltages (within and just below the specified values).
The fact that music sounds better late at night is because our ears have become more sensitive (a muscle in the ear relaxes)
I too have experienced the same music on the exact same setup sounding remarkably different during the day or in the evening.
The fact that I mostly listen to a battery fed X3 and battery fed Kameleon+ HD650 tells me the problem is my ears/brain as my gear is completely separated from mains.
Of course, there is also lots of equipment connected to mains and mains fed systems that can show 'problematic' behaviour when mains is 'dirty'
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Post by ronzo56 on May 14, 2015 14:01:17 GMT
Perfectly reasonable explanation Chris, but i still think the reason is more focused towards body clock and mind games!!. Mick. I know for me mood is a big factor. Sounds best on the weekends. If I have had a rough day at work sometimes I can't find anything that sounds good. I try changing headphones, and occasionally amps or tubes. Doesn't help. At that point I just switch off and try the TV or reading. Or lI'l go and complain about my day to my wife, have a beer and then try listening again latter. My enjoyment is really diminished If I am very tired as well. Should be sounding particularly good tomorrow night!! |
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Deleted
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Post by Deleted on May 14, 2015 18:40:36 GMT
I've used 'mood enhancers' for my entire adult life, until recently. Unemployment's a bitch!
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Post by musicman1806 on Jun 16, 2015 2:46:22 GMT
I have a questions about power tubes and driver tubes. Can a driver tube such as the 6SN7 replace a power like the 6AS7 ? I see that they have the same pin layout and the other specs seem pretty close as far as I can tell, but Im not an electrical engineer lol
Id love to be able to figure out how different tube specs work in a particular circuit but Im not at that level ... yet.
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Post by ronzo56 on Jun 16, 2015 15:53:56 GMT
Not an EE either, but I have heard an amp that was made by Eddie Current that used all 6SN7's. So they can be, it depends on the design of the circuit. I'm sure Frans can fill in the details.
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Post by bbball on Jun 24, 2015 17:58:18 GMT
I have a questions about power tubes and driver tubes. Can a driver tube such as the 6SN7 replace a power like the 6AS7 ? I see that they have the same pin layout and the other specs seem pretty close as far as I can tell, but Im not an electrical engineer lol Id love to be able to figure out how different tube specs work in a particular circuit but Im not at that level ... yet. New noobie here. Yeah, also want to know that. |
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Deleted
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Post by Deleted on Aug 4, 2015 21:33:55 GMT
If you guys had to pick one octal tube for the Ember what would it be?
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Post by Deleted on Aug 8, 2015 12:55:36 GMT
If you guys had to pick one octal tube for the Ember what would it be? *bump* Here's an interesting video showing the art of valve manufacturing.. |
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