[sup27606]

I bought the LF 339 from another Head-fi member and the tubes came with it. Here is a picture of the tube that I was referring to.

 

[wwmhf]

Thanks for sharing this info. Now, I know that this 339 amp can use another type of driver tubes.

 

[tintinsnowydog]

I bought the LF 339 from another Head-fi member and the tubes came with it. Here is a picture of the tube that I was referring to.

looks very similar in construction to the tung-sol mesh 6SJ7GT which is incredibly difficult to find for a reasonable price. I'd describe the 6SJ7GT tone slightly smoother,darker and less analytical than the RCA 5693 reds which seems to contradict your impressions of the 6SD7GT. Any chance someone can compare the two? I will be on the lookout for pairs of 6SD7GT now but cant see any with affordable shipping as of yet.

 

[tintinsnowydog]

As has been mentioned on the 6as7 tube rolling thread, 2x CV4079/A2293 can be rolled into the power tube slot with adapters (available on ebay). I had some initial connection issues since i couldn't get the tubes to sit properly/deep enough but with some considerable force they are now in nice and snug. They sound great, somewhere in between the GEC 6080 and GEC 6AS7G; slightly more musical and less analytical than the 6AS7G, with deeper/punchier bass, and almost as good separation/imaging/soundstage for which the GEC 6AS7G is the best I've heard (TS5998 a close 2nd but not as musical imo). They work great with mullard/telefunken EF86 for incredibly musical clarity on HD800 or with 6SJ7GT a smooth, relaxing but still textured sound. A viable substitute for the insanely expensive GEC 6AS7G as these are only around 10-20$ for NOS. Gain is very very high on these tubes, have the knobs at this position and -25dB through DAC, still moderately loud. Anyone else tried these tubes on LF339?

Added a picture, will add a lights off shot when it's night time over here. Looks a bit wacky but pretty cool at the same time

 

[sup27606]

looks very similar in construction to the tung-sol mesh 6SJ7GT which is incredibly difficult to find for a reasonable price. I'd describe the 6SJ7GT tone slightly smoother,darker and less analytical than the RCA 5693 reds which seems to contradict your impressions of the 6SD7GT. Any chance someone can compare the two? I will be on the lookout for pairs of 6SD7GT now but cant see any with affordable shipping as of yet.

If you search on eBay, currently a lot of 6SD7GT are for sale, and cheap! $12-$15 for a pair. One issue with these tubes is microphonics, but shouldn’t be a problem if there are no vibrations directly on the amp.

BTW, I found the RCA reds to be smoother with rolled off highs compared to the 6SD7GT, when combined with TS 5998. They have more bass, but loose, with less definition. I don’t know how much the sound quality differs from batch to batch, but I have two pairs of RCA reds, and they both sound like this.

 

[sup27606]

As has been mentioned on the 6as7 tube rolling thread, 2x CV4079/A2293 can be rolled into the power tube slot with adapters (available on ebay). I had some initial connection issues since i couldn't get the tubes to sit properly/deep enough but with some considerable force they are now in nice and snug. They sound great, somewhere in between the GEC 6080 and GEC 6AS7G; slightly more musical and less analytical than the 6AS7G, with deeper/punchier bass, and almost as good separation/imaging/soundstage for which the GEC 6AS7G is the best I've heard (TS5998 a close 2nd but not as musical imo). They work great with mullard/telefunken EF86 for incredibly musical clarity on HD800 or with 6SJ7GT a smooth, relaxing but still textured sound. A viable substitute for the insanely expensive GEC 6AS7G as these are only around 10-20$ for NOS. Gain is very very high on these tubes, have the knobs at this position and -25dB through DAC, still moderately loud. Anyone else tried these tubes on LF339?


Added a picture, will add a lights off shot when it's night time over here. Looks a bit wacky but pretty cool at the same time

Thats a very very interesting configuration. I can understand, this would be a viable alternative to the 5998 or the GEC 6AS7G, both of which can be insanely expensive.

 

[xtr4]

Dear all, I have a quick question. My previous config for tubes were CV1067 (drivers) and 5998 (power). My volume pot need only move to the 8 o'clock position to get nice and loud listening volume.
Now I've just bought EF86 and adapters. After replacing the CV1067, I need to now adjust the volume pot to the 12 o'clock position to get it loud enough but not even as loud as previous setup.
Could this be caused by the adapter + EF86. Also, there's static/hiss every time I'm adjusting the volume which wasn't present previously.

Forgot to add; 6XX are the cans used.

Thank you in advance.

 

[sup27606]

.

 

[sup27606]

Dear all, I have a quick question. My previous config for tubes were CV1067 (drivers) and 5998 (power). My volume pot need only move to the 8 o'clock position to get nice and loud listening volume.
Now I've just bought EF86 and adapters. After replacing the CV1067, I need to now adjust the volume pot to the 12 o'clock position to get it loud enough but not even as loud as previous setup.
Could this be caused by the adapter + EF86. Also, there's static/hiss every time I'm adjusting the volume which wasn't present previously.

Forgot to add; 6XX are the cans used.

Thank you in advance.

12 o’clock with 5998 and 6XX should be blistering loud! Also, I have never seen changing the drivers to change loudness, it’s usually the power tubes, and not to this extent. My first suspect would be the tubes, since the adapters are freshly made and new. The tube terminals could be dirty and oxidized, introducing additional resistance. Also, if you check web resources, there is mention of radio static and interference caused by dirty tube terminals, which could be the reason behind the hiss/static. May be, you can try clean the terminals with isopropyl alcohol.

 

[wwmhf]

There seems to be two issues here:

1. The noise when adjusting the volume: This might be a problem of the volume pot itself or the tubes that are too sensitive to vibrations. If you do not have this problem with you CV1067 tubes, then the noise is not caused by the pot.
2. The loudness: This issue might be caused by the EF86+adapter. The tubes might be too weak/old, the connection to the adapter is bad ... Changing driver tubes will vary the loudness a little, but not much.

 

[Jacobal]

Hey guys, if anyone wants to sell their 339 plus upgrade tubes setup, I’m listening.

 

[xtr4]

12 o’clock with 5998 and 6XX should be blistering loud! Also, I have never seen changing the drivers to change loudness, it’s usually the power tubes, and not to this extent. My first suspect would be the tubes, since the adapters are freshly made and new. The tube terminals could be dirty and oxidized, introducing additional resistance. Also, if you check web resources, there is mention of radio static and interference caused by dirty tube terminals, which could be the reason behind the hiss/static. May be, you can try clean the terminals with isopropyl alcohol.

There seems to be two issues here:

1. The noise when adjusting the volume: This might be a problem of the volume pot itself or the tubes that are too sensitive to vibrations. If you do not have this problem with you CV1067 tubes, then the noise is not caused by the pot.
2. The loudness: This issue might be caused by the EF86+adapter. The tubes might be too weak/old, the connection to the adapter is bad ... Changing driver tubes will vary the loudness a little, but not much.

Thank you for the replies. I have cleaned the terminals prior to inserting into the adapter. Maybe I have weak EF86

 

[MJS242]

You can do a 6336 as well

 

[wwmhf]

These 6336 might make the hot 339 amp even hotter???!!!

 

[sup27606]

Just rolled in the mullard EF86. Along with TS 5998, this combination gives phenomenal bass response, definitely adequate for the HD800. Needless to say, the TS 5998 also gives excellent 3D soundstage and imaging. So far, this combination is working out the best for the HD800, surpassing the other options I have tried.