Difference between mesh vs. solid plate 300B?


I am looking to replace my 300B tubes and I am considering the Emission Labs 300B. This comes in a mesh and a solid plate model. There are other valve manufacturers who make solid plate vs. mesh 300B's, e.g. TJ Full Music.

My question: Can one make a general statement that mesh sounds different to solid plate? If so, what are the differences?

(Second question: the EML 300B mesh has a clear warning not to run the tube at high bias. I am wondering if there are any Cary 211AE owners who are running this tube).
amfibius
I've never compared apples to apples - mesh plate 300B from TJ to their solid plate.

But, for what it's worth, I have compared the TJ mesh plate against Shuguang solid plate 300B, and the TJ were superior in every way. To me, they were most definitely worth the upcharge.
The meshplates are not standard Western Electric spec. 300B's - their plate voltage is down about 10%. They therefore can't be run in amps like the VAC Renaissance series that run 300B's near their maximum plate voltage.
After a few months, I finally found the answer to my own question on someone's blog. Link here: http://robertmusic.blogspot.com/2010/06/emission-labs-eml-5z3-revelation.html

"Now, first a word about mesh plates. There are some very shady marketers calling any plate with a hole in it a 'mesh' plate - such as the Sophia, Full Music, and TJ brands. This is complete bullshit. NONE of these are mesh plates. They are solid plate tubes with a bunch of holes punched in them. That is just plain false - mesh plate tubes have exactly that - a true wire mesh woven as the plates. Nobody but Emission Labs has done that incredibly difficult manufacturing process since the mid 1930's.

A real mesh is glorious to look at, but more importantly, the sole benefit of the mesh cannot be realized with a punched hole plate. That benefit is purely sonic. Mesh tubes have a wonderfully organic, euphonic, relaxed sound that is not veiled in any way - open, transparent, yet at the same time possessing a warm inner glow and sense of organic integration that solid plate tubes simply don't have to the same degree. There's something that just sounds very right, integrated and whole about mesh tubes.

That's been my experience with mesh power tubes - and yes, I do have NOS Perryman mesh 45 tubes from the 1930's, dead mint, to compare."

The guy is talking about a 5Z3 tube, but elsewhere on the site he makes a similar comment about 300B tubes. The ONLY true mesh 300B on the market is the EML 300B - all the others are "punched hole tubes" (as he puts it).

Looks like I will have to source a couple of pairs to try.
The best Mesh ever were AVVT's and the only that made today are EML's, heard that they are great to.

They should forbid to call tubes Mesh while they arent Mesh really

Most 300B amps cant use Mesh's

I’m sitting here and realize my current factory 300B’s are mesh plates lol. Full Music 300 B/n mesh plates. Sooo. The EML meshes may still be different? Or should I assume that this would mean that I can certainly run them if I desired? I only see the mesh plate disclosure about compatibility with amps, with the EML’s. No other mesh brand tubes. Maybe partly bc only EML make real mesh tubes anymore? Insight is welcome! I’m considering possibly getting a pair as well and comparing them to the KR's.
I'd like to revive this thread. I'm just starting out on the 300b journey, having recently picked up an old, orphaned Audio Electronic Supply SE-1 power amp. It comes stock with the lowly JJ 300b tubes and a pair of nice 5692 drivers, driven in turn by 12AU7s. Despite it's lowly pedigree I love the sound of this thing!

I also read the statement on the Emission Labs website about the "phony" mesh plates that are really simply solid plates with a bunch of holes punched in them. I get it.

However, I'm interested in the sound. And the journey for me is about comparative value and performance. It's one thing to claim that an EML mesh plate 300b sounds good - it should - because these things are really expensive. However, I've also read of those who prefer the sound of other, less expensive contemporary 300b tubes. And the TJ Full Music mesh plate tube has consistently gotten pretty good press for a couple of decades.

So, where does that leave us? I'd love to hear from those who've made the significant investment in the EML mesh plates and hear your thoughts on how they compare to other tubes. 
Not sure, but I think @charles1dad might have compared some within brand solid vs mesh 300bs... perhaps he'll notice the thread.
In my opinion Emission Lab mesh plates are worth the money. BUT, while they rarely have problems, they aren't good about honoring warranty on those rare occasions.
That may be who you are dealing with.  I have been an EML dealer for a couple of years and have found Jac to be extremely helpful in terms of warranty issues.  The only time it is a problem is if someone just ignores his advice and mis-uses a tube.  For instance, the EML Mesh tubes have a max plate dissipation of 28w vs. the standard 40w.  If you put them in the wrong amp and/or don't adjust the bias down and they burn up, he isn't going to honor the warranty.  Otherwise, the couple of failures I have dealt with were addressed immediately.  Jac even facetimed with a customer to help him modify the bias on an amp when he had an issue.  
I’ve listened to both the original EML solid plate 300Bs and EML mesh plate 300Bs for several years each without any problems. The solid plates are very good, while the mesh plates present a richer, more musical sound. Worth the money? Yes!

The only only ones that rate higher on my list are the Takatsuki and current production Western Electric, but only by a small margin. I’d put the Elrog at about the same level as the EML mesh, but the Elrog has reliability issues. If the current WE = 100, then the Takatsuki is a 99, the EML Mesh is a 97, and the EML solid plate is a 95. Having used two pairs of the original (1940s and 1960s) WE 300B for years prior to the EML’s, I would put the latter at 94 -- they have a great midrange, but fall short in the bass compared to the modern ones.

As usual, other listeners may differ in their pecking order or preference, so don’t take my word as an absolute. Your driver and input tubes, plus the overall build quality of your amps, have a great deal of influence, too.

Be careful to observe the caveats about the meshies -- 22W dissipation is recommended, with 28 watts the maximum. Most commercially built amps run much higher -- 38 watts isn’t unusual -- so you can’t just plug them into any ol’ 300B amp without doing the math.

For the 300B mesh plates, I run my 300B amps with about 350V on the plates, -73V on the grids, and with an 1100K ohm, 22W cathode bypass resistor. The cathode bypass cap is normally 20uF, 200V. That’s just a guide -- your amp may require different values to achieve 22 watts. The Emission Labs data sheet is helpful in that regard.

BTW, the choice of rectifier is critical to the sound of any 300B (or other power tube). For the vintage WE 300B, I preferred the vintage metal banded Amperex (Holland) 5AR4/GZ34. For the EML solid plate 300B, the best sound was with the Sylvania/Philips USA "Big Boy" 5AR4/GZ34, and for the EML 300B mesh, I prefer the 1950s/60s RCA 5U4GB. As usual, your listening pleasure may vary, but it pays to experiment with different numbers and different brands within each number until you reach the magic spot.

http://www.emissionlabs.com/datasheets/EML300B-mesh2.html

Cheers,
Joseph