Kofi Annan in: "300beee!" or "Kofi Gets a Toy" - diyAudio
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Old 28th December 2005, 12:42 AM   #1
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Default Kofi Annan in: "300beee!" or "Kofi Gets a Toy"

So the story goes, me and Mrs. Annan are about to have a bit of a windfall. Its never happened before to the Annans and probably won't happen again, so its time to think big, act irrationally and ooze irresponsibility. That means I get a toy.

Given that, the question is what do I build?

Now, I still have my hooks in the Bevois Valley push pull amplifier-- I'll probably order parts for that really soon. But the fact remains that I think I could tackle a project that would require more financial resources as long as I act before Mrs. A changes her mind.

I have thought about a 300b SET for some time now, and I think I'd maybe like to build a pair of monoblocks. The question, of course, is which design?

Now I know I'm going out on a limb here asking for people on DIYAudio to espouse an opinion, but maybe just this once you could let me know how you really feel.

In a post earlier, I mentioned the possibility of working on a 300b and Thorsten's "Monkey on a Stick" was mentioned as being a frontrunner. Another possibility, of course, would be the FI Primer or the Angela Instruments version.

Still, I'd like to hear what you think would be best for me to rush headlong into without regard to my future financial well being. I'd say I could spend about $1K or so on the project, although Mrs. Annan and I have not discussed the dollars (so don't tell her, OKAY?!?).

Can I get a witness?

Kofi
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Old 28th December 2005, 02:17 AM   #2
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Hi Kofi,

I thought tubelab had a 833 project going seemed interresting and you could offset your heating bill substantially thus saving more money in the future!

apart from that I have no SET experience but good on ya ;o)

Robert
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Old 28th December 2005, 12:34 PM   #3
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Thanks for keepin' it real, Robski666! I'll check it out.

As far as the 300b goes, I think the drd 300b in this thread is really interesting. I was pointed to this one before, but I never acted-- sometimes it takes me a while.

So, any thoughts on this one? I built Thorsten's Phono Pre and I absolutely love it, so this might be a good fit for me.

Kofi
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Old 28th December 2005, 01:07 PM   #4
Gluca is offline Gluca  Italy
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Mr. Annan

everyone built a 300B once in lifetime. Is it going to be you the next one? I remember a nice and recent project by Jim Doyle ... the guy used a cheap & strong & politically correct 811A (class A2) parafeed at 450V B+.

Mr. Annan will you be the next one?

Gianluca
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Old 28th December 2005, 01:36 PM   #5
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Hey Kofi...

Please do yourself a favour and build the d3A/300B DRD thingie. It's really worth it...

Just my 2 cents.

Best regards,

Luis
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Old 28th December 2005, 01:46 PM   #6
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Quote:
I think the drd 300b in this thread is really interesting
As good as any out there in my opinion. The thing is that once you have the 300B's, powertransformer, chokes, output transformers, psu caps.. you can go ahead and change the driver configuration to see which you like most...without any big expense... then when you like what you have .... you can start adding a trick or tweak...

At the moment I am playing with a d3A choke loaded driver...simple, effective and good sounding. The drd types are the exception really in that they need higher voltages than average...so once you have power transformers that have multiple taps..the 300b world is your oyster.
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Old 28th December 2005, 06:04 PM   #7
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Well, if your looking for pearls such as this, hamfests are fabulous places to visit. You wont find many 300Bs, but all sorts of iron and glass baubles to snatch from the deep.
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Old 29th December 2005, 03:28 AM   #8
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Hi Kofi,

sorry about the 833 thing i couldn't help myself thinking SET and remembering the pictures Greorge posted of his 833 looked awsome, and I was just trying to help out with justification for spending more money, ;o)


I also looked at Welborne site and my they are expensive and the drb isn't that complex. I kinda like the version in the link although if it's SET why use a pentode as a driver?

Robert
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Old 30th December 2005, 12:02 PM   #9
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Sorry for the delayed response...

Quote:
everyone built a 300B once in lifetime. Is it going to be you the next one?
Let's hope Mrs. Annan doesn't have a change of heart.

Quote:
Please do yourself a favour and build the d3A/300B DRD thingie. It's really worth it...
Luis! Good to have a response from you! I have questions:

First, where did you get your motor run capacitors and is there a reason for paralleling these rather than going for one value that's close to the sum of the parallelled caps? Also, is the amorphous OPT really necessary or can I get away with the non-amorphous? In addition, is there a way I can get the word "amorphous" into more conversations? Its a cool word.

Amorphous.

Also, the D3a driver tube may be a bit tough to find. Any recommendations on a substitute?

Quote:
As good as any out there in my opinion. The thing is that once you have the 300B's, powertransformer, chokes, output transformers, psu caps.. you can go ahead and change the driver configuration to see which you like most...without any big expense... then when you like what you have .... you can start adding a trick or tweak...
That's what I'm talkin' 'bout!

Quote:
sorry about the 833 thing
Why be sorry?!? I love the open exchange of new suggestions. Not in a like-I-love-Mrs.-Annan-after-I've-had-a-couple way, but its love just the same! Thanks!

Also, instead of monoblocks, I may try and cut a corner and get one power supply for the whole shebang. Would I just need to increase the mA rating for the power transofrmer?
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Old 30th December 2005, 12:12 PM   #10
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Default Amorphous, amorphous wherefore art thou?

Quote:
Also, instead of monoblocks, I may try and cut a corner and get one power supply for the whole shebang. Would I just need to increase the mA rating for the power transofrmer?
Basically yes....that is all there is to it. Don't forget that you need enough juice for the filaments as well. Not just for your b+.

Amorphous, well yes..you can skip the amorphous transformers..there are many factors that make for a good sounding output transformer...the core is only one of those factors.

But I suspect once your amp is up and running..you will start wondering how big an improvement it would be to get amorphous...In that case go straight for the amorphous...if you are a headstrong, balanced sort of person. In other words not an audiophile but a music lover..force yourself to accept that a wonderful sounding 300b amplifier need not sound just that 5% (if that) better than it already is (maybe not even better but different) and spend the extra cash on "software" to feed into your amp...or a nice gift for Mrs. Annan.


Amorphous....amorphous.....and I sing to myself...what a wonderful word..
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