TAD 6L6GC-STR and Mesa STR-440-Same Tube?

[cscotto]

Hi,

I am about to buy a quartet of TAD 6L6GC-STRs for my Roadster. Visually comparing a picture of a TAD 6L6 to a Mesa STR-440 leads me to believe they are the same tube, and both of them seem to be from Ruby Tubes. I cannot see any difference. Also, there is no difference in price (41.95 from the Tubestore and 42.00 from Mesa), so price is not a factor. My question is if they are the same tube, why is the TAD better than the Mesa? Does TAD test them differently? Do they supply tubes where the current draw brings up the bias? Simply put, what makes them different? I am just curious.

All the best.

 

[bradg]

Yes, I believe they are the same tube.

 

[cscotto]

Thanks for the reply. Does anybody know what differentiates TADs from Mesas?

 

[R_ADKINS80]

TADs are black plate tubes modeled after rca's.......mine bare ZERO resemblence to my 440's what so ever.

 

[Jacko123]

I received some TADs this week and I'm replacing the stock Mesas ... I take some side by side pics to show.

 

[cscotto]

I received some TADs this week and I'm replacing the stock Mesas ... I take some side by side pics to show.

Hi,

That sounds great. I was comparing the picture of the TADs on the tubestore's website with the STR-440s I have. I like the STR-440s in the Roadster, so if the TADs are high performance version of the Mesa tubes, I will probably like them even more.

 

[bradg]

According to this site, they are the exact same thing.

http://www.watfordvalves.com/product_detail.asp?id=1811

 

[R_ADKINS80]

regardless of what that site says, I have both and I can tell you they are worlds apart in terms of tone.

 

[cscotto]

According to this site, they are the exact same thing.

http://www.watfordvalves.com/product_detail.asp?id=1811

Hey,
Thanks for finding that information. I forgot to check Watford valves. They have a lot of good information on their site. If the valves are different, perhaps it is in the grading.

 

[R_ADKINS80]

Just for some extra clarification in this matter I just did a close side by side inspection of these two tubes. NOT EVEN CLOSE to being the same. The STR440 has grey plates that have 2 holes on either sides where you can see the internals. The TADs have shiny black plates with no holes. Also the 440 has a single halo ghetter that is parallel to the top mica spacer.....the TAD is a double halo ghetter and they are at 45deg angles forming a kind of "roof" shape as they are very close together. In terms of tone I find the 440's to be very peaky in the mids, shallow bass and rather harsh on top. The TADs are very deep in the bass (more so than any other 6L6 I have ever used in anything) have a very smooth mid range when bias up around the mA's in the mid-high 30's where a 6L6 should be. The top end is very smooth and creamy. I can take the trebel knobs as high as 2:30-3:00 without getting ice picky. I hope this helps anyone who is considering either one of these tubes and hope it lays to rest the idea that they are the same tube. The only similarities these two have is that they are both STR (Special Tube Request) tubes from the chinese factory. The 440s were ordered to a set of specifications and the TADs were obviously ordered to a completely different spec as well.

 

[cscotto]

Just for some extra clarification in this matter I just did a close side by side inspection of these two tubes. NOT EVEN CLOSE to being the same. The STR440 has grey plates that have 2 holes on either sides where you can see the internals. The TADs have shiny black plates with no holes. Also the 440 has a single halo ghetter that is parallel to the top mica spacer.....the TAD is a double halo ghetter and they are at 45deg angles forming a kind of "roof" shape as they are very close together. In terms of tone I find the 440's to be very peaky in the mids, shallow bass and rather harsh on top. The TADs are very deep in the bass (more so than any other 6L6 I have ever used in anything) have a very smooth mid range when bias up around the mA's in the mid-high 30's where a 6L6 should be. The top end is very smooth and creamy. I can take the trebel knobs as high as 2:30-3:00 without getting ice picky. I hope this helps anyone who is considering either one of these tubes and hope it lays to rest the idea that they are the same tube. The only similarities these two have is that they are both STR (Special Tube Request) tubes from the chinese factory. The 440s were ordered to a set of specifications and the TADs were obviously ordered to a completely different spec as well.

Thanks for the info. Although I have a bunch of Mesa STR-440s, I don't have any TAD 6L6s yet. My comparison was based solely on the available pictures of TADs. Before I shelled out another $100.00 on tubes, I just want to make sure I am not spending money on something I already have. You description of the TADs is exactly what I am looking to get out of the tube in my Roadster. I like the Mesa STR-440s, but from your description of the TADs, they will take the tone to the area I want.

 

[R_ADKINS80]

No problem dude. I love these tubes and they are money well spent. As long as you get them in Mesa specs I recommend you run them in the EL34 bias setting using the tube rectifiers. Total God tone right there.

 

[Jacko123]

Hey guys, I took some pictures of both tubes this morning and posted them side by side. I'm a tube newb so I didn't know what angle to shoot but you'll see some big differences jump out:

They look alike from far away but you can they're two different tubes when you look closely. Dunno if it's relevant but my Dual Recto's previous owner told me it was built in 2002 and this is an original power tube.

I'll see if I can record clips tonight with both tubes.

 

[cscotto]

Ok, those are obviously different tubes, at least different variations of the same tube type: double versus single getter, black plate versus gray, etc. Here is a link to the first picture of a TAD I used for comparison from the tubestore:

http://us.st12.yimg.com/us.st.yimg.com/I/thetubestore_2043_11041035

Here is a link to supposedly the same tube from the TAD site (click on the picture of the tube to enlarge it):

http://www.tubeampdoctor.com/product_info.php?products_id=813

The tubestore's TAD looks more like the Mesa, but the picture from the TAD site looks like the ones in your photos.

 

[fishyfishfish]

Might be some type of picture error on the site? The TAD 6L6GC's that I am using now have black plates and aside from NOS, are the best 6L6 I have ever used.

 

[cscotto]

Might be some type of picture error on the site? The TAD 6L6GC's that I am using now have black plates and aside from NOS, are the best 6L6 I have ever used.

Definitely an old picture. Maybe that is what TADs looked like a few years ago. It is still curious that Watford valves (they know their stuff) would say they are the same. Maybe it is the same thing; no one knows the website is out of date.

Well, at least I can drop another $100.00 on tubes without feeling like I am wasting money (I just spent about $300.00 on tubes :evil: ). Thanks for all the help.

 

[Koreth]

I recall reading somewhere that TAD designed their 6L6GCs themselves, basing it upon NOS GE and RCA 6L6GCs, and then commissioned a Chinese factory to manufacture them. But for the life of me, I cannot find where this was said or who it was said by. While I might want to believe something like that is true, without a source, I can't count it as anything beyond hearsay or Internet rumor. (which I'm now helping to spread without meaning to by even mentioning it. ). Has anyone else head/read something similar? Where from?

Being based on NOS designs is what is supposedly the case with the New Sensor re-issues of Mullard and Tung-Sol tubes out of the Reflektor plant in Russia, but reviews I've read of those tubes by those who've heard the originals state that the re-issues don't sound anything like the originals. Maybe someone hear has heard both TAD 6L6GCs and NOS RCA or GE 6L6GCs? How do the two compare?

 

[cscotto]

I recall reading somewhere that TAD designed their 6L6GCs themselves, basing it upon NOS GE and 6L6GCs, and then commissioned a Chinese factory to manufacture them. But for the life of me, I cannot find where this was said or who it was said by. While I might want to believe something like that is true, without a source, I can't count it as anything beyond hearsay or Internet rumor. (which I'm now helping to spread without meaning to by even mentioning it. ). Has anyone else head/read something similar? Where from?

Being based on NOS designs is what is supposedly the case with the New Sensor re-issues of Mullard and Tung-Sol tubes out of the Reflektor plant in Russia, but reviews I've read of those tubes by those who've heard the originals state that the re-issues don't sound anything like the originals. Maybe someone hear has heard both TAD 6L6GCs and NOS RCA or GE 6L6GCs? How do the two compare?

Ok, so I bought an octet of TAD 6L6GC-STRs from the Tubestore. My original question was prompted by the picture they have on their website. I searched around and actually found a description of the TAD that matches what other people have written. The tubes arrived today, so I compared them with the Mesa STR-440s. I think you are correct Koreth that they are probably manufactured by the same Chinese factory that makes the Mesa tubes. They have similar glass bottles and bases and some other parts are similar like the mica spacers. However, that is where the similarity ends. The rest of the tube is very different, and the pictures in the other post highlights the difference.

The biggest difference is in the sound. Damn! TAD 6L6GC-STRs are the best 6L6s I have heard outside of NOS tubes. They have a lot of power. I put them in my 2:100 with the Recto Pre feeding the power amp. I had JJs in the 2:100, which had a lot of power (more than Mesa STR-430s), but these tubes took it up a notch. The bass is amazing, articulate, clear, and chugs with ease. I even had to turn it down because I thought I would blow a speaker. Great compression and grind. These tubes were made for Rectos. Solos sustained and sang. This tube is not lacking in any part of the frequency spectrum. For the first I get what the Mesa manual has been saying about the presence control. I can now jack the mids and presence and get grind not fizz. I am going to put a set in my Roadster as well. In fact, I like these so much, I may stockpile them. The Tubestore sent them with a rating of 21 (I told them it was for a 2:100), which seems perfect for power amp. If you have a Recto, I recommend trying the TADs. They are worth every penny.

Edit: by the way. I had a bunch of the old GE tubes. These sound just as good.

 

[R_ADKINS80]

You ought to hear them in a recto with the bias switch set to EL34. it actually gets the bias up to the high 30's low 40's depending on tube/diode bold/spongy settings and they really come to life.

 

[cscotto]

You ought to hear them in a recto with the bias switch set to EL34. it actually gets the bias up to the high 30's low 40's depending on tube/diode bold/spongy settings and they really come to life.

I have heard about running 6L6s with the bias switch set to EL34 to bring up the bias. You have not had any problems, no glowing tubes? The TADs can run up to 70% of rated plate dissipation, so the low 40s should not be a problem. I am just nervous about wrecking something.