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    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

What are the requirements for driving a 300B?

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Vinylsavor

Vinylsavor

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Joined 2002
vinylsavor.blogspot.com/
Hi!

radiotron said:
Thomas, is there anything new you wish to share regarding IT designs?
Click to expand...

Nothing really new. One of my favorite interstage transformers is still the Tango NC20. Tribute can make something similar. If on a budget, Lundahl has a broad offering of different ITs. They just released a new type. I wrote about it on my website but have not tested it yet.

Thomas
 
Vinylsavor

Vinylsavor

Member
Joined 2002
vinylsavor.blogspot.com/
Hi!

Andersen said:
I've just found this: 1985 Book which is quite similar with my initial project, right? Any consideration to make it possible?
Click to expand...

Just note the 100 Ohm input impedance. Not many preamps can drive this properly. Sakuma uses Preamps with power triodes and often with power amp output transformers.

Also note that Sakuma is after a certain sound, not necessarily the leats colored and linear design. This amp will certainly not have a wide bandwidth with this arrangement.

I like Sakuma-sans design philosophy a lot and use similar concepts myself. But I'm after a more neutral sound and decent bandwidth.

It's all a matter of your goals in sound.

Best regards

Thomas
 
Vinylsavor

Vinylsavor

Member
Joined 2002
vinylsavor.blogspot.com/
Hi!

analog_sa said:
Not a 300B fan in general but I bet this sounds divine.
Click to expand...

I'm not a big fan of the 300B either! I very much prefer the 45 or 801A.
The 300B amp was a customer request. With the 10Y as driver it gives much of the good properties of the thoriated tungsten filament tubes. I liked this 300B amp a lot. It used old manufacture WE 300Bs. Tango interstage and output transformers.

Best regards

Thomas
 
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pieter t

Disabled Account
Joined 2009
tribute-audio.nl
Andersen said:
Many thanks for all responses. It seems that 10Y is the tube of choice to drive 300B. Can you all please advise me a most simple 10Y driving 300B push pull schematics?
Click to expand...

Hmm, there is not likely a "most simple schematic".
IMO with a (pair of) 10Y driving 300B's in push pull you opt for a high quality design, where cost is not the most important factor.
Lynn Olsen's Amity and Karna amplifier designs are good examples of DHT's driving DHT's.
 
Vinylsavor

Vinylsavor

Member
Joined 2002
vinylsavor.blogspot.com/
Hi!

Pieter mentioned already: A 300B with 10Y driver is not going to be simple. Filament supplies need utmost care if you want this to be hum free and good sounding.

There are a lot of PP schematics available from Sakuma which you could adapt to your needs.

I'd only recommend such an amp with directly heated drivers if you already have some experience in amp building and budget is not an issue.

Best regards

Thomas
 
M

MelB

Member
Joined 2005
My Parallel 300B circuit. I started out using a 6SN7 connected in parallel to drive them but it did not sound very good....maybe bad operating point don't know. Then I went to a 6V6 triode connected...then to the 6L6 version (7027A). This circuit represents a lot of listening. The grid chokes on the 300B's are definitely worth a try. They are going cheap on Ebay right now. As far as the 7027A goes I just had a bunch.
 

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