[FullRangeMan]

That I didn't know Fullrangeman! I thought 300b was most linear tube for audio but limited in power like 2A3 !

The original 300B was released 1938 for mid-range only (voice) in cinema and telephone where it work best, but currently manufactures may have changed it, EML have various versions.

[Jaytor]

Those mono blocks look nice!

Thanks. I think in the right system, 300B SET amps can be an excellent match. With my current (GR Research Line Force) speakers, the high frequencies sound extended with plenty of sparkle but very smooth and non-fatiguing. But I do agree with others that the midrange is where the 300B really excels. In my system, vocals are glorious. Bass performance seems pretty good, but I haven't done extended listening without my separately powered subs. Certainly with the subs, the bass is deep and tight.

Here's a few more pictures of my build.

[Kw6]

Thanks. I think in the right system, 300B SET amps can be an excellent match. With my current (GR Research Line Force) speakers, the high frequencies sound extended with plenty of sparkle but very smooth and non-fatiguing. But I do agree with others that the midrange is where the 300B really excels. In my system, vocals are glorious. Bass performance seems pretty good, but I haven't done extended listening without my separately powered subs. Certainly with the subs, the bass is deep and tight.

Here's a few more pictures of my build.

If you sold it how much would it go for?

[Kw6]

The original 300B was released 1938 for mid-range only (voice) in cinema and telephone where it work best, but currently manufactures may have changed it, EML have various versions.

Yes, 300b is good for mids. Missing some treble information like for trumpet. Is 845 & 6c33c tube better?

[mresseguie]

Thanks. I think in the right system, 300B SET amps can be an excellent match. With my current (GR Research Line Force) speakers, the high frequencies sound extended with plenty of sparkle but very smooth and non-fatiguing. But I do agree with others that the midrange is where the 300B really excels. In my system, vocals are glorious. Bass performance seems pretty good, but I haven't done extended listening without my separately powered subs. Certainly with the subs, the bass is deep and tight.

Here's a few more pictures of my build.

Stunning eye candy. I'd love to hear it someday. I may have my own 300b amp next year. 

[FullRangeMan]

Yes, 300b is good for mids. Missing some treble information like for trumpet. Is 845 & 6c33c tube better?

The opt are important but I think its better they have bass IMO, 6C33 are linear under 30W dissipation.

[Jaytor]

If you sold it how much would it go for?

I started with the ANK C-Core Interstage PSET Monoblock kit since this was my first tube build. Before ordering the kit, I had decided that I wanted to build my own chassis to move all the connections to the rear and provide enough room for some enhancements. ANK gave me a modest discount on the kit because I didn't need the chassis, but I ended up using relatively few parts in the kit (transformers, chokes and a few caps), so I ended up paying probably double what it would have cost to source similar parts elsewhere.

I used Audio Note silver tantalum resistors everywhere, high quality connectors, silver PTFE wiring, etc., and added a lot of other upgrades (TentLabs current regulated DHT filament supplies, DC regulated heater supply for the driver tube, balanced input transformer, soft-start, Maida regulator for the driver stage, speaker output relay with delayed start, etc.

With the WE 300B tubes, I have close to $15K invested for the pair. The custom chassis for the two amps was the most expensive part - more than then 300B tubes. But I don't do DIY to save money. I enjoy the process of designing and building the projects, and in this case, I'm thrilled with the results.

Stunning eye candy. I'd love to hear it someday. I may have my own 300b amp next year. 

Thanks. I see from your profile that you live in Oregon (at least part time). If you are in the Portland area, I'd be happy to demo them for you.

[FullRangeMan]

Congratulations Jaytor, I would like to be your neighbor.
Do these AN resistors are Carbon or Metalfilm ?

[mresseguie]

Thanks. I see from your profile that you live in Oregon (at least part time). If you are in the Portland area, I'd be happy to demo them for you.

Sending you a PM.

[Jaytor]

Congratulations Jaytor, I would like to be your neighbor.
Do these AN resistors are Carbon or Metalfilm ?

The Audio Note resistors use Tantalum film with non-magnetic silver leads. I didn't experiment with other resistor types in this amp, but have experimented with swapping resistors in the preamps I've built. I've compared these with inexpensive metal films, Takman metal and carbon film, and Vishay Z-foils. The Z-foils are the most transparent, but the AN silver tantalums are a close second and sound a touch richer. They are also available in a wider range of values and power handling, so are generally more useful in tube circuits.

They are pretty pricey though, particularly in the 2W size. But I didn't that many resistors in this amp. 

[FullRangeMan]

Great info Jaytor, Thanks a lot for your detail ed post, I posted this question on other fórum and have no useful results.

[Kw6]

Hey Fullrangeman,

Are the mids juicy in the 6c33c tube? Also are the mids holographic like El34s.

[FullRangeMan]

Hey Fullrangeman,

Are the mids juicy in the 6c33c tube? Also are the mids holographic like El34s.

It will depend on the OPT quality and type, not sure how many harmonics you wish, for the old-fashioned musical tube sound use a EI transformer, C core transformer will delivery a more neutral sound, other parts as resistors and rectification also will play a rule on the final sound character.

[Kw6]

Thanks again Fullrangeman! I could kick myself when Almarro set 6c33c were around and passed on it!🙁

[FullRangeMan]

On the original question the 6c33 have a warm and musical tone, the traditional sound of tubes.

[Kw6]

On the original question the 6c33 have a warm and musical tone, the traditional sound of tubes.

Nice! That's what I figured! No doubt the Lamm 2.1 SETs monos were legendary!

[Docere]

300B is not even linear, hype.

The thing about linearity is that it depends on the operating points and load. Have you compared the curves and run the calc? I have, and the 300B is rather competent. Not my personal favourite, but saying it is not linear (at least within its reasonable operating parameters) shows up the limits of your understanding. Sure some tubes are better in one or two areas, but the 300B is a solid all-rounder. If treated well, 10,000 or perhaps even 40,000 hr lifetimes are possible… and although that goes for most quality DHTs, the 300B can achieve that at useable power levels. I would not want to use them in parallel though - should not be needed with moderately efficient speakers. And I’d prefer them run at relatively high voltage/low current (and high load) operating points.

The second-most sterile sounding tube amplifier I’ve heard ran 6c33c tubes… but sure, you can warm up any amp with component selection, if you are willing to throw away some musical expression. Same with EI transformers: if you want to introduce avoidable, albeit pleasing compromises (for some people), use them. I prefer musical expression, flow, authentic tone, texture, and a sense of touch without thickening and/or bass softness. For some music it can work nicely, for other music, not.

We do not share the same opinions. But they are just opinions.

Minor edits for clarity only.

[FullRangeMan]

The thing about linearity is that it depends on the operating points and load. Have you compared the curves and run the calc? I have, and the 300B is rather competent. Not my personal favourite, but saying it is not linear (at least within its reasonable operating parameters) shows up the limits of your understanding. Sure some tubes are better in one or two areas, but the 300B is a solid all-rounder. If treated well, 10,000 or perhaps even 40,000 hr lifetimes are possible… and although that goes for most quality DHTs, the 300B can achieve that useable power levels. I would not want to use them in parallel though - should not be needed with moderately efficient speakers. And I’d prefer them run at relatively high voltage/low current (and high load) operating points.

The most second-most sterile sounding tube amplifier I’ve heard ran 6c33c tubes… but sure, you can warm up any amp with component selection, if you are willing to throw away some musical expression. Same with EI transformers: if you want to introduce avoidable, albeit pleasing compromises (for some people), use them. I prefer musical expression, flow, authentic tone, texture, and a sense of touch without thickening, blurring, and/or bass softness. Listening to amps with EI transformers, IME, always reminds me I’m listening to - for some music it can work okay, for other music, not.

We do not share the same opinions. But they are just opinions.

Big patriotism at any cost, buy american.

[Docere]

Big patriotism at any cost, buy american.

Are you saying my comments are based on blind patriotism? How did you arrive at that? Your speculation about my motives is not even close. I’m not American. Nor do I have any particular interest in buying American.

[FullRangeMan]

Are you saying my comments are based on blind patriotism? How did you arrive at that? Your speculation about my motives is not even close. I’m not American. Nor do I have any particular interest in buying American.

10,000 or perhaps even 40,000 hr
Well, this looks like exactly the WE site speech talk for its new 300B.

There is amps with the 6C33 that have good sound as Almarro, Lamm, Joule-Electra, Ayon etc and others that have bad sound, as the 6C33 is a low tension voltage regulator not a power tube the 30/35W dissipation limit must be respected, above this the problems start to appear.