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Beginner looking for guidance into tube sound.

Hello all, I am looking for some input on the best way to add tubes to my current mess. I currently have what I am sure everyone here would consider barely a step up from my parents zenith HI-FI circa 1977. please keep in mind I am lucky if I can afford to look in the window of an actual audio store. 
I currently have a Peachtree nova 300 and a Marantz CD player and a pair of monitor audio silver 500 speakers. A friend gave me a blue sound node 2i also. I have always wanted a tube powered amp. I see these Chinese amps like the Muzishare X7 and Willsenton R8 that have lots of great reviews. Or maybe a tube DAC. Then I see the Black Ice for ss-x. Each having less tubes respectively. Not sure how much that matters but I would think the more tubes the more tube sound one could expect. I would like to be in the $1000. range but would go to $1500 if I had to. My goal is to find the best most cost effective way to enter the tube world.  
johnfritter
johnfritter OP
62 posts
 
@rocray I spotted that Aric Unlimited last night and am interested. But am curious if having the variable output will it mate with the Peachtree. I assume that is the reason for the variable output, compatible with more equipment correct? My goal today is to try and verify what Peach tree recommends. Then look into the variable output option as I have no previous experience. If it will mate up I think that might be the best way to go at this point. 
artemus_5's avatar
artemus_5
1,923 posts
 
I suspect your head is spinning now. There is never just the right amount of info available. Either too little or too much. And it can go from one to the other really quick.
Go ahead and build the ST-120 kit. I bought my ST70 assembled by Bob. I hear that the kits have good instructions. And Bob is always easily reached. Besides, you will save some $$$ and I believe it will meet your need and sound really good.  FWIW, I have Don Sachs custom build of this kit. It sounds very good
hilde45's avatar
hilde45
4,974 posts
 
Regarding matching, here's an email I got from Almarg, an expert and a gentleman. RIP.


On matching Preamp and Amp

Almarg:

"To assure impedance compatibility the 10x rule of thumb guideline should be applied at the audible frequency for which the output impedance of the component providing the signal is highest. In most cases impedances are specified at a mid-range frequency such as 1 kHz. It is very common for tube preamps to have output impedances at deep bass frequencies that are much higher than that specified value, often 2K or 3K or even 4K ohms. That rise at low frequencies results from the output coupling capacitor that is used in the majority of tube preamps, and also in a few solid state preamps. The impedance of a capacitor increases as frequency decreases.

So ideally the 10x rule of thumb guideline should usually be applied based on the output impedance at 20 Hz, in the case of a tube-based preamp. If as is often the case the component’s output impedance at 20 Hz is not known, and is not indicated in published measurements (such as those Stereophile often provides), and if the use of an output coupling capacitor in that component cannot be ruled out based on available information, to be safe a considerably higher ratio than 10x should be used, something like 50x or 75x IMO.

This applies, btw, to tube-based source components as well as to tube-based preamps.

Also, to clarify a common misconception I should add that failing to meet that guideline does not necessarily mean that there will be an impedance compatibility problem. It depends on how much **variation** there is in the output impedance over the frequency range. But meeting that guideline (at all audible frequencies) assures that there won’t be an impedance compatibility problem.

I should note also that a significant number of tube-based preamps use coupling transformers at their outputs, and therefore avoid that low frequency impedance rise. Although depending on the specific implementation transformer-coupled outputs might have downsides of their own. Atma-Sphere MP-1 and MP-3 preamps, btw, cleverly avoid the use of both capacitors and transformers at their outputs. (I’m not sure about the UV-1). As far as I am aware they are unique in that respect, among tube-based preamps.

Best regards,

-- Al"


Post removed 
rocray's avatar
rocray
1,448 posts
 
Hi johnfritter,
  you are absolutely correct about the variable output control on the rear. Me personally,I find this one of the best features ever. I run different amps through my systems. Some very low gain First Watt amps,and a higher gain pair of Monarchy amps.  Having that feature makes amp matching easy for me.  The Aric pre will also allow you to go crazy with tube rolling too. In fact,if I was in a little different position,I was going to pick up that pre for my second system. 
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