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Romy the Cat wrote:

It is not a the thread about Allnic but LCR RIAA correctors, still there was something expressed in here about the Allnic LCR phonocorrector… and  I feel bad about it. It is not that I don’t think that Allnic LCR phonocorrector deserve positive mentioning.  Furthermore, I heard recently Allnic MC cartridge that I also liked. The problem that I have is that a remarkable amount of idiots visit my site, stupidly search for the brands that they want to buy and use this site (and many other sites) and a guidance for some kind of audio “recommendations”. I can’t stress how much I hate it and how I am bored I with those people. I invests effort do not any explicit reconditions at my site. Still, I got for the last few days emails from the site visiting Morons asking me if I fell that Allnic phonocorrector is better than two other phonocorrector and if I think that they need to buy it. What the idiots! Anyhow, to offset my positive comments about Allnic phono I am harry to inform you that Minority is not alien to Allnic. I local guy own Allnic preamp that sounded like shit. Ok, I need to tell you that it did not sound like a bad sounding preamp – it sound worse. Regardless what you feel in the preams it out 10dB of dynamic range – I am not exaggerating – it converted the whole spectra of sound into one octave wide of 10dB range and it was it. I was mocking the preamp owner and proposed him to throw this preamp into the head of the idiot who was responsible for this sound. The Allnic’s preamp is just one stage transformer-coupled buffer – how complex shall it be? We opened up the unit and the very first think that shocked me was that Allnic used my phonostage’s 7788 tube as driver for the preamp.  The 7788 tube that used for microphone preamp and MC cartridges, the tube that has 0.5V bias and no ability to drive anything, Allnic used to be fed from line-level input signal, that might saving as high as 2-3V. Can you pretend what would happen indirect heated signal time you drive with signal 6 times more then it’s bias? It is not class “B” operation anymore but the class “F”, as an abbreviation from the “Fucked operation”. Funny  that the Allnic web site say that preamp use 7721 tube, the one that I used in my phonocorrectors output: http://www.allnicaudio.com/eng/products/view.htm?brandcode=0010030000000003&page=1 The 7721 is a driver tube with 1.7V on grid; it is still low but already something. Also the 7721 can driver some load. Replacing the stupid in this location 7788 to the 7721 did “fixed” the preamp. Now the interesting question: how the hell the 7788 made into the Allnic’s preamp?  The guy who owns the preamp bought it brand ne and never opened it up.  It is not to mention that he just a user who does not know or care what is the difference between volt and ampere – he is highly not technical and very far from the nuts and bolts of audio.  The Allnic designer would hardly made this mistake – you need to be a completely idiot to use 7788 as a driver – the Allnic designer doe not strike me as an idiot. The distributor who sold the unit would also hardly make the substitute: the 7788 is twice more expensive and those industry primps would kill themselves for extra saving, it is not to mention that they are in most cases are too audio-retarded to do anything with hands or brain.  So, how the 7788 made into the Allnic preamp? I did a courtesy call to the Allnic distributor informing him that I have in my hands a horribly performing brand new unit and I see that it uses 7788 tube as a driver. Instead of expressing regrets and proposing overnight the right tubes to fix the unit the Moron begin to question my assessment of the sound with 7788 and proposed me to talk with the designer.   Why do I need to talk with the designer – to confirm that the distributor is a dupe who has no idea what he sells? Oh, such a classified information!!! Anyhow, I think I am too hard on the poor Allnic people.  It is most likely not their fault and the customers with screwed sound is not their liability. It is most likely the UPS people sting in this brown track, opening the Allnic units and replace the tubes. Nevertheless, if you do like the Allnic phonostage then you need to open it up and to confirm that Allnic did not use the 845 tube in input gain stage – they can as my experience shows…

In the post above where I was blaming Alnic for use 7788 with .5V on grid was not absolutely accurate. I spoke with the Alnic designer who informed me that 7788 use as a triode with 3.5V on grid. I do not remember that in my case 7788 has 3.5V but I think it was 1.7V but I would not insist that I am right. If you wish to see how 7788 behave as a Triode then look here - there is plenty of data.

http://www.diyaudio.com/forums/tubes-valves/102393-7788-triode-curves.html

According to Alnic designer the 7788 were not made in his preamp accidently but was substituted because according to Alnic it “sounds better”. I very much disagree with Mr. Park – he feels that 7788 is a wonderful driver. I do not like the 7788 as a driver it has no current - who need such a driver. It is difficult to dispute anything with Mr. Park as he overly polite .  Also, I did not particularly cared about Mr. Park’s “theory” as I has right in my home his Preamp with 7788 and 7721 and what I heard was beyond any need to debate. Mr. Park was trying to present the differences as “personal preferences” but it was very far from it. Playing the preamp with 7788 has dynamic range of 15dB and it no needs to talk furthers a about any preferences. The 7721 did wipe out the problem, making the Alnic’s Preamp to sound acceptable.

I need to make very clear that I very much do NOT supports the Alnic’s idea about the transformer coupling. The advantages that Alnic’s enumerated at this site:

http://www.allnicaudio.com/eng/products/view.htm?brandcode=0010030000000003&page=1

I would call very controversial and in many case I would not agree with them. I would not debate it here just will mention that the transformer coupled preamps are very sensitive to the load impedance and it changes very dramatically harmonics of the output tube. I loaded Alnic’s Preamp to EVS attenuator and each click of it made the Alnic to sound differently. So, everything was clean – the 7788 was the Alnic’s mistake, the 7721 was fine. I can question that 7788 has more gain and the OPT ration for the 7721 and 7788 has to be different but… it is not might preamp to care too much.

The Mystery came next. The Alnic’s owner invited me in a few days as he bought more tubes and to do some other thing and he did listen the Alnic’s Preamp with different lording amps and different tubes again. THIS TIME the 7788 did not behave as bad as before and we fed the 7788 and 7721 with the same input voltage as before. There was still a difference between 7788 and 7721 and the 7721 was better but this time it was not day and high result and there was no compression to barbaric 15dB. I was sitting in there, listening, flipping the tubes like an idiot and was not able to understand why the difference that use to be so huge suddenly went to much less scale. I still have no explanation and I was not alone who witnessed it.

Anyhow, here is what I think I would do if I use the Alnic’s Preamp. Get rich the 7721 and 7788 and to put in there my 6E6P-DR in triode mode. The tube has very same pins and a full equivalent.  Increase the plate voltage to 200V. The 6E6P-DR is 8W driver it is a very powerful driver with 33 times gain. I would driver it with 22mV that would make it ~ 5W. I n this mode the 6E6P would have 1K on pals and the ratio of the transformer need to be adjusted accordingly – it looks like Alnic doe good transformers as it will not be hard for them….

Anyhow, it looks like Alnic’s Preamp  is very versatile unit and you can put in there many tubes… Still, I would not use the 7788….

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