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845 SET amp recommendations

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I have an super cool schematic originally for a 845 power tube which turned out to be useful for the russian 6c33 but it is expensive to build!

maybe the design is pure utopia... a 6sn7 B-follower driving a C3g cathode follower paired with C3o current sink...

It provides low gain for using no feedback and can drive any big triode through a capacitor.

Will you be willing to share it with us?
 
Guys,

For those that are in the US, the best and safest choice is Tubelab SSE or SE amp. There are alot of great review about this amp. There's even a separate Vendor forum for Tubelab in Diyaudio forum just to discuss, help, guide, and troubleshoot Tubelab amp.

Keep in mind, George( tubelap amp designer) only provides PCB board, you have to source all the components, OPT, choke from different sources. He had all the great details and clear instruction how to put everything together from his website. I myself bought his SSE and SE boards but did not have the time to sit down and put everything together yet. Got so many projects piled up. You know the drill

Tubelab SE | Tubelab

Regards,
Tom
 
I would be very, very careful of anything coming from China!
Unless you have a skilled technician that can check it before you plug it in.
A fair point, but I bought a pair of Ming Da 845 monoblocks in about 2005. They were the importer's own pair, so let's say they were made in 2004. I used them with just a bit of valve rolling, and bucking transformers as they were the 220V version (240V in the UK), sold them 2 or 3 years ago, and with even fancier valves in they are still going strong, and equally importantly, sounding good. So that's 13 years and counting!
 
Do a search here or on Google, and you can get a sense of the issues involved, also as mentioned earlier by Celsius, the components, in particular the OPT.

Jazbo , I do not want to buy Music angel and mode it , if that is what you meant by issue. I think only good quality component I would end up using will be the chassis.
I am interested in implementing the circuit provided by Dietmar. It is a full design of a SE amp. Do you think it is a flawed design? If so please provide specifics.
I am not interested in any SET amp , only 845.
Any experience with Bez amps ?
 
Forget 845 or other big triode as 211,805, unless its GM70.
211,845,805 are all expensive tubes even the Chinese brands and they are not military tubes, not to mention that US tubes will breaking the bank.

With the KT150 in SE you can get 13W or UL 25W w/this chinese inexpensive amp 6SN7+KT150 will made a great sound.
There is a $200 offer in coupon in this shop in 3 days.
https://pt.aliexpress.com/item/KT12...-adjustment/32459475648.html?isOrigTitle=true
The KT designation is "kinkless tetrode".
Amplifiers emulating triodes by 'strapping' such tubes, to short internal connections do not have the same performance specification or sound as big power triodes.

Personally, I would recommend designs with smaller, more common tubes such as the Russian 6c33c dual triode.

845, 211 are broadcast tubes, and are expensive to replace.

http://www.thetubestore.com/Tubes/Big-Power-Tubes/6C33C-B

Sent from my Nexus 6 using Tapatalk
 
Have you heard an amplifier using this tube? I run DHT amps that use type 50 tubes. There's little comparison.

Remember that many of the designs published in the last twenty years were based on available surplus tubes - not on merits of a particular design.

Sent from my Nexus 6 using Tapatalk
 
There is nothing wrong going for the 845, it sounds very good on alnico magnets drivers.. it has a lot of distortion in the bass region, and creates an euphoria effect, it sounds so good with old opera recordings and is so emotive.

The biggest downside is it will sound like junk on almost all speakers if no feedback is used, and there is almost no point of using feedback for a s.e.t. 845 tube, unless using it in push-pull, you want to hear all the distortion...
 
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