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Recommendations for a mid-priced tube preamp

If you don’t want to put together your own gear but still have a great sounding pre that’s also hugely moddable down the road then the Yaqin 12b might work for you. Lots of reviews and info online. It is diode rectified with 12ax7’s for phono and 12au7’s for line, both rca. It also has two outs. One .7 and the other .25.

In my experience it performs better than it’s price point by a large margin. I also found it hugely susceptible to tube rolling….in a good way.

There is a reasonable field of choices in your budget. Have fun.
 
I tried a Xiangsheng 728A (wrote it up at
https://audiokarma.org/forums/index...rt-xiangsheng-728a-tube-pre-amplifier.963788/ )
Pleasant, but you could tell there was a piece of equipment in the chain. Ideally, components should be "invisible," no?

It was better than an Emotiva BasX PT1, which I quickly returned on the 30-day trial policy.

But far above both is the Van Alstine Transcendence 10 RB. Natural, full, none of the over-brightness of so much SS. The price is almost twice your ceiling. That was more or less my ceiling, too, but I am glad I went for it. I expect it to last a long time, so I excuse the cost by spreading it out over the years.
 
20220830_203845.jpg 20220830_203845.jpg great thread here! i could use a little help in this area. looking for sound advice. i have a knight kp 70 pre amp i pulled out of a nonworking reel to reel . trying to hook it up to my sansui 2000 but keep getting a hum out of it. it works . i can get sound through it but my question is : does it need to be modified and is it worth it ? do i sell it and buy an integrated sansui power amp ? im obviously new to tubes and not sure which direction to take this thing. thanks in advance for any input .
 
Mikehook said:
View attachment 2662221 View attachment 2662221 great thread here! i could use a little help in this area. looking for sound advice. i have a knight kp 70 pre amp i pulled out of a nonworking reel to reel . trying to hook it up to my sansui 2000 but keep getting a hum out of it. it works . i can get sound through it but my question is : does it need to be modified and is it worth it ? do i sell it and buy an integrated sansui power amp ? im obviously new to tubes and not sure which direction to take this thing. thanks in advance for any input .
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You should start a separate thread in the appropriate forum. You'll get more answers that way.
 
another option is the zerozone marantz 7 clone offered by several folks in China. pretty hard to beat at the price point you are targeting.
 
mcgjohn said:
another option is the zerozone marantz 7 clone offered by several folks in China. pretty hard to beat at the price point you are targeting.
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That or the cj clone, which aren't really clones. Lots of gain, but they sound pretty darn good for 250 bucks.
 
opnly bafld said:
Specs have the output impedance as 100k ohms. :yikes:
I emailed them in June asking about it and never received a reply. :dunno:

Edit: I sent Frenzel another email and they answered on a holiday, yes its output impedance is 100,000 ohms.
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I asked about that on the thread I started about the Frenzel preamp and was told as long as the output impedance is lower than the input impedance it is fine. I am running the Frenzel into a Dynaco ST-70 [upgraded] and the ST-70's input impedance is 470k so it shouldn't be an issue. Higher into lower impedance is where the problem comes in. I am brand new to tubes so I am only going by what I am told and read about.
 
cartop said:
I asked about that on the thread I started about the Frenzel preamp and was told as long as the output impedance is lower than the input impedance it is fine. I am running the Frenzel into a Dynaco v ST-70 [upgraded] and the ST-70's input impedance is 470k so it shouldn't be an issue. Higher into lower impedance is where the problem comes in. I am brand new to tubes so I am only going by what I am told and read about.
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The ST-70 is very high and makes sense since the Dynaco tube pre is high. 60 years ago it was more typical I think.

The vast majority of amplfiers (solid state included) that list an input impedance are nowhere near that high. Tube amps tend to be higher than solid state amps, but my guess is that many are @100k or lower, especially more modern ones. Solid state amps are usually well under 100k, I have seen many A/B around 20k and D are often 10k.
 
opnly bafld said:
The ST-70 is very high and makes sense since the Dynaco tube pre is high. 60 years ago it was more typical I think.

The vast majority of amplfiers (solid state included) that list an input impedance are nowhere near that high. Tube amps tend to be higher than solid state amps, but my guess is that many are @100k or lower, especially more modern ones. Solid state amps are usually well under 100k, I have seen many A/B around 20k and D are often 10k.
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Great info, I started with the Frenzel feeding my Onkyo M-504 and it sounded so good I had to go find a tube amp. Luckily I found the upgraded 70 and I love it. I have to look into what the output impedance of the 504 is. Thanks opnly bafld. :bigok:
 
cartop said:
Great info, I started with the Frenzel feeding my Onkyo M-504 and it sounded so good I had to go find a tube amp. Luckily I found the upgraded 70 and I love it. I have to look into what the output impedance of the 504 is. Thanks opnly bafld. :bigok:
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I should have noted also that there have been many tubes preamps made in the last 30 years or so that have an output impedance of 2k or less. Frenzel obviously intends this to be used with high input imp. tube amps.

M-504 input impedance 20k
The amp is direct coupled, so no extra roll off of bass, just a softening of high frequencies with a high output imp. preamp.
 
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Thanks for the info. I only know the 504 sounded great with the Frenzel but not as good as the Frenzel sounds with the ST-70. :music:
 
cartop said:
Thanks for the info. I only know the 504 sounded great with the Frenzel but not as good as the Frenzel sounds with the ST-70. :music:
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It just seems like a very odd design choice on their part. :dunno:

A low output impedance tube preamp will work well with any amp, even SS or Class D. Since so much of the interest in tube preamps seems to be from people who want to add some "tube sound" to their SS and Class D based systems, you would think Frenzel would be building something that's suited to that market. I suspect that most tube amps don't even have an input impedance over 100k.
 
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