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Marketplace => Black Market => Topic started by: Baltazar on January 23, 2019, 10:15:49 AM

Title: WTB: AC701K tube
Post by: Baltazar on January 23, 2019, 10:15:49 AM
Hey,
Looking for a AC701k tube.

Best
Title: Re: WTB: AC701K tube
Post by: TLRT on January 24, 2019, 05:13:52 AM
How many do you need? (still have around 50pcs)
Title: Re: WTB: AC701K tube
Post by: Phrazemaster on January 25, 2019, 01:44:51 AM
How many do you need? (still have around 50pcs)
Are these the "K" variation? How much are you selling them for?

Thx

Mike
Title: Re: WTB: AC701K tube
Post by: Glutamatjunkie on January 27, 2019, 08:49:25 AM
701k? How much???
Title: Re: WTB: AC701K tube
Post by: duantro on February 03, 2019, 03:58:34 PM
yes, price?
Title: Re: WTB: AC701K tube
Post by: RuudNL on February 05, 2019, 04:02:28 AM
As far as I know, all AC701 tubes produced by Telefunken went straight from the factory to Neumann.
There they selected the tubes with the best specifications and lowest noise.
The 'rejects' went back to Telefunken and were sold.
Nowadays it is very rare to find a 'good' AC701 and if you can find one, prices are extremely high.
https://tubedepot.com/products/ac701
So if you find an AC701 today, the question remains: is it a real 'good' AC701, or is it a reject from Neumann?
(Also there are a lot of 'fake' AC701's on the market.)
Title: Re: WTB: AC701K tube
Post by: Phrazemaster on February 05, 2019, 05:41:32 AM
As far as I know, all AC701 tubes produced by Telefunken went straight from the factory to Neumann.
There they selected the tubes with the best specifications and lowest noise.
The 'rejects' went back to Telefunken and were sold.
Nowadays it is very rare to find a 'good' AC701 and if you can find one, prices are extremely high.
https://tubedepot.com/products/ac701
So if you find an AC701 today, the question remains: is it a real 'good' AC701, or is it a reject from Neumann?
(Also there are a lot of 'fake' AC701's on the market.)
Towards the end of production of the tubes, tolerances/build quality got so good they stopped bothering with adding the “k” designation. I believe these tubes have serial numbers ending in “03”

Supposedly they are generally excellent if you can find them. But I’m no expert.
Title: Re: WTB: AC701K tube
Post by: RuudNL on February 11, 2019, 02:15:25 PM
Since 1965 Telefunken only made frame grid AC701 so there was no need to specially mark them. But careful:Telefunken also sold RFT Neuhaus-made ones under the "Telefunken" name that can be quite noisy and more microphonic than the Tele-made ones.
If you buy an AC701 make sure you get an original, still in its sealed box, because 95% of all AC701 tubes out there for sale are Neumann rejects.
Title: Re: WTB: AC701K tube
Post by: Phrazemaster on February 11, 2019, 03:44:57 PM
Since 1965 Telefunken only made frame grid AC701 so there was no need to specially mark them. But careful:Telefunken also sold RFT Neuhaus-made ones under the "Telefunken" name that can be quite noisy and more microphonic than the Tele-made ones.
If you buy an AC701 make sure you get an original, still in its sealed box, because 95% of all AC701 tubes out there for sale are Neumann rejects.
Good to know. Thx RuudNL!