RIAA Tube Preamplifier EF86/EL84

This preamplifier was created 9 years ago and was released in many modifications. It has received many rave reviews from users. The average level of satisfaction with the product was something like this:

Dear Abbas
You are a real artist in your field!
You did a fantastic job with that phono-preamp. Now after +100 hours, I can say that your fine construction is lifting my system to another level of musical expression and I know that this part of the chain will no longer be the weakest anymore.
Med venlig hilsen
Mikael

User’s Review

Introducing the latest version, signature, which offers the highest level of sound quality you can get from these boards.

The circuit is very simple. This is a pentode, voltage amplifier, and passive RIAA circuits in parallel with the anode resistor. Such a scheme ensures the least loss of important musical information when passing through the jungle of electronics. The output stage is based on EL84 in a triode mode.
You won’t find a preamp on the audio market that has an output stage on this legendary tube, but it is still a very good solution. I do not know why no one uses it. EL84 in triode mode has a gain of about 15, low internal resistance and excellent sound.

The preamplifier has a very high overload capacity. Gain is 44db at 1kHz
flatness 0.2dB

Output stage:
bandwidth 10Hz-250kHz , -3db
The maximum amplitude of the output voltage at 1 kHz is about 200V peak-to-peak. Try to find a similar preamp in a high end store!

Now about the features of the signature version

Audionote tantalum non magnetic resistors in the EF86 anode and in the correction circuit
Black gate and audio note capacitors.
Telefunken transformers manufactured in 1938, These inductors are exceptionally musical
Siemens and Bosch PIO capacitors
Wirewound handmade capacitors in RIAA circuits
EI 84 power transformer . It is a modified Siemens transformer taken from German audio equipment.

Tube rectifier EZ80 / EZ81. You can use both valves without any circuit modifications.

The preamp requires about 200 hours of warm-up to perform at its best. This product is not for connoisseurs of cold, thin sound, taken as a standard in high-end industrie. This device will not give you a chance for dispassionate contemplation. You will be forcibly involved in the process of perceiving music.
There is no sterile cleanliness and whiteness, predictability and boredom, characteristic of modern electronics, developed in the dull office of a famous company.
Here it’s the other way around. A riot of colors, mood contrasts and unexpected twists. A violin playing a cantilena will amaze with its tenderness and ability to sing, while aggressive rock will impress with strength and energy. The tone will be wide and powerful, and trebles are natural, without ringing and ostentatious brilliance.
You will hear the voice of another era, the golden period of valve technology. In those days, engineers knew a lot more about what music was for. It is needed in order to excite hearts and make us more spiritual.
We did not just go back in time, we tried to take the best of the past and combine it with some of the latest advances in technology, such as superb modern audio note resistors and black gate capacitors, alongside vintage Allen Bradley and Telefunken components. Low distortion, good detail clarity, articulate bass, short signal path, no negative feedback, powerful output stage.

As usual, there are non-standard solutions that are specific only to our product. These are special boards covered with gold and without a mask. Violin varnish coating, special preparation of electronic parts — resistors and capacitors. Handmade wire made using vintage copper, vintage Kester solder was used to assemble.

Please pay attention! We use wires, resistors and capacitors only in accordance with the direction of best sound. In the audio world, few people care about this. This way of working takes much more time.
It is all more like a building of musical instruments than electronics manufacturing. Each device has individual features, unlike a faceless conveyor product. That is our approach.

Note! We provide a set of cheap Soviet tubes, you must choose high quality tubes yourself! Sorry, but in these difficult times we do not have the opportunity to keep a large number of expensive valves in stock and make a selection.

Dimensions: 470/230/130
Weight: 10kg

Regards, Abbas