Going To Experiment With An Active Gain Stage With Tubes!

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Neonknight
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Going To Experiment With An Active Gain Stage With Tubes!

Unread post by Neonknight »

This should be an interesting experiment. I was attempting to purchase the matching T3000 transformer from a seller on UKAudiomart, but he never responded.
In the process of looking around I came across a Conrad Johnson HV1. This is an active head amp but it uses Nuvistor tubes. Very few components do use this gain device, and all of them that I have heard sound remarkable. The price was quite reasonable, so I bought it last night. Should have it in about 5 to 7 days, and we are going to give it a shot with the MC3000.

This seems to be a forgotten head amp but was well received in the day. One owner posted it can be a bit microphonic, I wonder if that is due to the tubes they had installed. I also am curious if it inverts phase like some CJ components do, and if so I will take care of that at the cartridge leads as inverting speaker wires is a pain in the butt.

Should be a grand experiment!

Vinyl-ant
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Re: Going To Experiment With An Active Gain Stage With Tubes!

Unread post by Vinyl-ant »

I built a phono stage with nuvistors (6ds4 and 2ds4 which are identical but with a 2.1v heater)
They are really very nice. They are not microphonic in my experience, they are not glass inside, they are metal cans. They can be a little noisy with hiss at higher volumes, but other than that i didnt find any particular drawbacks. Most of the nos stock seems to be in the states. Bases are a little fragile, and pretty small so watch what you are doing if you swap the nuvistors out
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Geoff.R.G
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Re: Going To Experiment With An Active Gain Stage With Tubes!

Unread post by Geoff.R.G »

Neonknight wrote: Thu Sep 16, 2021 2:44 pm This should be an interesting experiment. I was attempting to purchase the matching T3000 transformer from a seller on UKAudiomart, but he never responded.
In the process of looking around I came across a Conrad Johnson HV1. This is an active head amp but it uses Nuvistor tubes. Very few components do use this gain device, and all of them that I have heard sound remarkable. The price was quite reasonable, so I bought it last night. Should have it in about 5 to 7 days, and we are going to give it a shot with the MC3000.

This seems to be a forgotten head amp but was well received in the day. One owner posted it can be a bit microphonic, I wonder if that is due to the tubes they had installed. I also am curious if it inverts phase like some CJ components do, and if so I will take care of that at the cartridge leads as inverting speaker wires is a pain in the butt.

Should be a grand experiment!
I’ll be controversial and say that you don’t need to worry about phase inversion because you aren’t using any other source at the same time. It is irrelevant to the sound output but if you want to try doing something about it let us know what you find.

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