[mraudio]

Hey guys!  How many hours are recommended for break-in/burn-in for a LS100?  Maybe split out the actual unit time and tube time, if possible.   

Thanks so much!!!

[Toon]

Dan quotes around 400 hours for the MWI caps he uses to come good. Using the supplied tubes, I found that pretty significant changes to the LS100's tonality were still occurring out at 300 hours, but only subtle differences after that.

[mraudio]

Toon,

Thanks!  I thought it was around 200 hours, so I have a ways to go.  I am using the Shuguang Black Treasure tubes and have read they take about 200 hours also.  So, at the 400 hour mark, I should be good to go on all counts.   

[dminches]

Not to dig into your wallet but you should try other tubes too. I have found many of the NOS 6SN7s sound better than the BTs. When rectifier are you using?

[mraudio]

dminches, thanks for your reply.  After very extensive research, I found the Black Treasures to be "THE" tube to use according to 99% of what I read.  I do have several others that I bought before the BT's, so I might try them.

I am using the Mullard 5AR4 (GZ34).  That's what Dan had recommended to me and what I've read also was the one to use.

[modwright]

Another GREAT 6SN7 replacement is the Sophia Electric 6SN7.  It has the same form-factor as the Black Treasure, except with clear glass and brass clad base.  I know that Galen Carol Audio - www.gcaudio.com is a distributor for Sophia Electric tubes.  They are BEAUTIFULLY made and sound JUST as goo as the Black Treasures in my opinion.

The GZ34 by Mullard or Amperex or Philips are also my top choice for rectifier.  For a slightly warmer and more laid back presentation, the 5U4GB is another option.  The 5V4G and 5V4GB are also valid rectifier options.

Thanks,

Dan

[mraudio]

Dan, thanks so much for the reply!  The Sophia was the other tube you had mentioned to me to try.  I did buy a pair along with the BTs.  I will try them next.

[dminches]

dminches, thanks for your reply.  After very extensive research, I found the Black Treasures to be "THE" tube to use according to 99% of what I read. 

IMHO, THE tube is the tube that produces a sound that you like the best.  I don't feel that there is an absolute best tube.  It really depends on your taste in sound.  You should view tubes the same way you view any other piece of equipment.  They all have their own sound signature and you have to see how you like it.

Having said that, I have tried the BTs in both the Modwright Transporter and the LS-100 and I prefer the TungSol Black Glass Round Plate hands down.  But YMMV.

Enjoy your tube rolling.  I highly recommend doing this to find the combination that suits your taste the best.

[modwright]

I couldn't agree with you more!  That is why tube-rolling is a great way to 'tune' your system to your own personal tastes.

Take care,

Dan

[nnck]

Is there a good source(s) to go to to find the Mullard/Amperex/Phillips GZ34 rectifiers that Dan mentions? I take it these are NOS?

And to dminches - how about the TungSol Black Glass Round Plates? Where can those be found?

[mraudio]

nnck, I found my Mullard and Amperex GZ34s (5AR4s) on Audiogon.  They seem to be on there pretty often, but sell very quickly.  I bought enough to last a few lifetimes.

I looked for the TungSol Black Glass Round Plates that dminches recommends on a Google search, but make sure you're sitting down when you see the prices I saw.

[dminches]

Here some sources for tubes: https://www.tubeworld.com/index_high.htm, http://www.audiotubes.com/.  You can also use ebay but you need to know the sellers to be comfortable.

GZ34s are not that expensive.  TS BGRPs will cost $500 per pair, or more.   

[vintagebob]

So I got a pair of the Sophia Electrics and a Mullard rectifier.  My balance is now skewed over to the left channel.  The right channel works but at a reduced output.  Can I just re-adjust the balance or should I be worried about something else?

[dminches]

I would switch the tubes and see if the issue goes to the other channel. If it does, you have a bad tube. Do you have another pair of 6SN7s to try in place of the Sophias?

[vintagebob]

Hey, thanks for the help.

I already swapped the tubes back and that wasn't it.  I've also swapped out my amplifier which didn't help.  My spare preamp and DAC are loaned out at the moment so I can't swap them out right now.

I'll figure it out eventually.  I'm a tube newbie so I just assumed the tubes were the problem, especially since I had just swapped them out.  Hopefully I didn't do anything to the preamp.  Dan would kill me after he went the extra 200% to get my LS100 to be PERFECT.