[BigTony]

Quote:

Originally Posted by ogygia /img/forum/go_quote.gif anyone conduct my test?

The hum is very quiet, and as soon as the power is turned off the hum dissappears, and as soon as the power is turned on the hum returns.

 

[ogygia]

Quote:

Originally Posted by BigTony /img/forum/go_quote.gif The hum is very quiet, and as soon as the power is turned off the hum dissappears, and as soon as the power is turned on the hum returns.

Sorry for that....My guess may right, so no matter how you all burn in your amp...hum will be still there. The only way is to recable the signal transfer cable inside the amp.

My guess about the designer of darkvoice gone might be right as well....

 

[ogygia]

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339...........

 

[gbacic]

They don't use top quality tube sockets or caps in their amps. So if you upgrade those (as I intend to eventually) the hum should disappear or lessen.

 

[ogygia]

Quote:

Originally Posted by gbacic /img/forum/go_quote.gif They don't use top quality tube sockets or caps in their amps. So if you upgrade those (as I intend to eventually) the hum should disappear or lessen.

So...from what you say, many tube amp should have hum....right? they are not using M-cap or Jensen caps and telfon golden plated ofc copper socket......

 

[Mullet]

To wait or not to wait... that is the question...

I have a box of tubes that I've acquired for my 332c -- RCA JA6AK5W, CV4010, Tung Sol 5654W, Ericsson 403B, WE403B... and both Svet and Uly power tubes.

I've got maybe ~50 hours burned in on this amp. Should I just say F it and just pop in some of the *better* tubes and call it a day? What would you do? Resist the urge and wait til 100 hrs? or just DO it!

 

[gbacic]

Quote:

Originally Posted by ogygia /img/forum/go_quote.gif So...from what you say, many tube amp should have hum....right? they are not using M-cap or Jensen caps and telfon golden plated ofc copper socket......

Well, I meant that they aren't even using very good ones, just decent. I don't expect them to be using the super audiophile sockets/caps. I just mean that if you replaced the sockets with some Woo Audio ones it would probably reduce the hum.

@mullet:
I would just put some of the better tubes on, the other components will still burn in on the amp, and you'll get to burn in your better tubes earlier rather than later.

 

[Mullet]

OK... couldn't resist. That didn't take much prodding.

I'm using the Ulys with some Tung Sol 5654s. The highs seem a little more prominent and brighter than the stock tubes. Hrmmm. Sounds good. The mids are nice and forward. The lows... well... seem a little less prominent. This is with Andrew Birds latest album -- Noble Beast. Will try something more bass heavy in a bit.

One more thing to note... as soon as I popped my HD650s on with the new tubes... BAM! Hum in the right channel with some microphonics as well. Put on the black tube protecter thingies and the microphonics disappeared. Hums still there. With the stock tubes -- I had barely noticeable hum unless I was using IEMs. I'm going to swap the tubes and see if this is a tube burn in thing or a right channel thing.

 

[Mambosenior]

What a shame to hear of all the hum issues. My DV 3322 never developed a hum, no matter which tubes I used. Hope the LaFigaro folks design a fix for this issue soon.

 

[BigTony]

Well after 2 weeks and lots of burn in a few lasting thoughts:

On the downside:

Way too much gain, even with -10db attenuators its LOUD ... Going to borrow/buy a sound meter to record the levels, but in comparison with my other amps, min. on the 332S is about 75% max. on my Jade.

Hum ... this started out quite noisey, and has dropped off quite alot, but its ever present, and if you turn off the power the hum dissapears before the music does - so its looking like is a circuit design and not a tube/burn in issue. The hum isn't noticable when music is playing, and to give a fair comparison - listening to an orchestra you can often hear (with cans) various rustling, coughing, scraping of chairs etc - well the hum level is at that level, you can hear it, but its not in your face. Can I live with it ... well....

And the upside:

Sound :- well it just sound gorgeous, really full rich tone with the HD-650's. You can hear that wonderful full base, tight, resonant, full of life; and the mids and highs are clear and crisp. All the microdetails are present, lots of hidden sounds etc just pop out unexpected at you; the soundstage is just that little bit fuller than the Jade for example, there is more room around instruments, everything is just that little bit more in focus. You can follow an instrument easily, it never gets congested. I've switched back and forth with the 332S and the Jade and it just has that little something extra.

In balance - do the pros outweigh the cons?

Very tricky .. The black background of the Jade is great, it allows you to forget about the amp/headphones and just enjoy the music, that little hum on the 332S just stops you short of forgetting the gear.. maybe its because my mind is trying to trick me; is the hum gone? ah no.. there it is!

 

[xmdkq]

Quote:

Originally Posted by BigTony /img/forum/go_quote.gif Well after 2 weeks and lots of burn in a few lasting thoughts: On the downside: Way too much gain, even with -10db attenuators its LOUD ... Going to borrow/buy a sound meter to record the levels, but in comparison with my other amps, min. on the 332S is about 75% max. on my Jade. Hum ... this started out quite noisey, and has dropped off quite alot, but its ever present, and if you turn off the power the hum dissapears before the music does - so its looking like is a circuit design and not a tube/burn in issue. The hum isn't noticable when music is playing, and to give a fair comparison - listening to an orchestra you can often hear (with cans) various rustling, coughing, scraping of chairs etc - well the hum level is at that level, you can hear it, but its not in your face. Can I live with it ... well.... And the upside: Sound :- well it just sound gorgeous, really full rich tone with the HD-650's. You can hear that wonderful full base, tight, resonant, full of life; and the mids and highs are clear and crisp. All the microdetails are present, lots of hidden sounds etc just pop out unexpected at you; the soundstage is just that little bit fuller than the Jade for example, there is more room around instruments, everything is just that little bit more in focus. You can follow an instrument easily, it never gets congested. I've switched back and forth with the 332S and the Jade and it just has that little something extra. In balance - do the pros outweigh the cons? Very tricky .. The black background of the Jade is great, it allows you to forget about the amp/headphones and just enjoy the music, that little hum on the 332S just stops you short of forgetting the gear.. maybe its because my mind is trying to trick me; is the hum gone? ah no.. there it is!

6J1 - ³É¶¼Ô£ÇÚÒôÊÓƵ¹¤×÷ÊÒ - Õý¹æ³§¼Ò½»Ò×Çø - µ¨ÒÕÐùÒôÏì²ÄÁÏÍø ÒôÏì|½»Ò×|µç×Ó¹Ü|µ¨»ú|µ¨»úÍøÕ¾|µ¨»úÂÛ̳|µ¨»ú²ÄÁÏ|Ê ä³öÅ£|±äѹÆ÷|µçÔ´Å£|µç×è|µçÈÝ - Powered by Discuz!

Use This Tubes hum is very quiet。

 

[gbacic]

The hum in my old DV332 has almost disappeared. It was pretty noticeable at first and now it is almost not there.

 

[BigTony]

The hum isn't from the tubes, all the tubes i've used in the (which include the ones in your post) hum; the hum is predominatly in the left-handside, no amount of switching tubes around chamged the hum. Some tubes added there own noises, but none removed the hum.

 

[BigTony]

Just a quick point. I used a sound meter to test the levels out of my HD 650's and DT 770's - both came to within 2db. Max was 72db, at my normal listening level with the 332S - which i guess is fairly quiet.

 

[gbacic]

That is reasonably quiet. Where was the knob when you measured 72dB on the 332s?