Any experience with Chinese SET amps?

[kauai82]

I have experimented with inexpensive (cheap ) Chinese tube preamps and integrated amps. The problem with them is that the tubes that come with the units are not very good and you need to upgrade them to get decent sound. It looks like your deal includes some up graded tubes. The other problem is that the quality control on the entry level tube amps is hit and miss. There is a high failure rate out of the box. If you like the sound of the unit for sale I would definitely consider it. However, there is another path to take that I highly recommend. It will get you a very nice tube sound without the bloated bass and a very sweat midrange. It will run you about $900 to $1000 used for an integrated amp or about $1200 for a stand alone amp.  The company is PrimaLuna. Its products are manufactured in China, designed in the Netherlands. It has a very good reputation for SQ and workmanship. It has been in existence for about 12 years. It has a USA based dealership and repair center in Upland CA.


I have no relationship with the company, but after owning a used PrimaLuna Prologue One 35 watt per channel I can attest to liking the tube sound. I bought my unit on Audiogon  for $920 including shipping about two years ago. Due to my recent retirement and downsizing of my house coming soon I had no need for my office system in the coming months. I decided to sell the PrimaLuna and buy some more audio/video goodies for the man cave. I sold the PrimaLuna for $925 about two months ago. In the 40 years I have been dealing in this Audio/Video hobby this is the only time I have sold used equipment for more than I bought it for. The PrimaLuna sounds very good. Much better than your entry level Chinese tube amps that you are looking at. It is built like a tank and will last you years. My integrated amp was made in 2005 and looked and sounded as good as I have heard in many auditions. For a time I was a member of the Los Angeles/Orange County Audiophile Society and this is where I was introduced to the company. I did not want to shell out the $1600 for a new one and bought used. The PrimaLuna held its own in SQ with tube amps costing much more in price. 

If for some reason if you decide to buy your local Chinese equipment and want to upgrade or change direction back to solid state in the future be prepared to take a bath on your audio investment. The person selling your Chinese Amp is taking a huge hit on his original purchase. The tubes if they were purchased new are about half to two-thirds the price of the original amp. The stock tubes that came with the unit are not worth anything on the used market. Just because the amps are made in China does not make them automatically bad or not as good as amps made in other countries.  The problem with low end Chinese Amps is that they don't cost much to make labor wise and the parts in them are very cheap. Because shipping from China is now so much more expensive than it use to be the manufacture's are cheaping up on the power transformers which drive the tubes. The better transformers weigh a lot more and that drives up not only the cost of the amp but the cost on shipping it.

You will discover that the weight of the amp combined with the amount of wattage it puts out is a good determination of the quality of the unit. Most of your cheap Chinese amps come in about 8 to 15 pounds if they are putting out about 8 to 12 watts per channel.  For example the Yaqin and PrimaLuna amps that put out 35 watts per channel weight in the neighborhood of 40 pounds. I have not actually heard Yaqin  tube amps but they run in the range of new for about $600 to $900 dollars. However since they don't have much if any local dealerships in the U.S. and their resale price is not good (around $275-350) used.   These of course are my opinions and YMMV but there are numerous people on this forum that have owned PrimaLuna and have had good experiences with their product.  Wish you luck in your pursuit of that "tube" sound. Matt

[brubacca]

PrimaLuna is great gear. They have a great reputation. These are outstanding push-pull amps.

[audiophill]

This is my 76 pound Chinese push pull amplifier. It has 12 tubes in it. 4 kt100 tubes, 4 12AX7 gold tubes, 2 12BH7 gold tubes,and 2 12 AU7 gold tubes. Puts out 50x50 watts and it sounds amazing!

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[KeithL]

NOTE:

You need to distinguish between "SET amps" and "tube amps" and "Chinese tube amps".

A SET amp is a "single ended triode" (SET is an acronym).
SET amps are characterized by relatively low power, relatively high distortion, and a very tubey sound.
SET amps tend to have a monotonic distortion product; their distortion starts out rather high, and increases more or less linearly as you turn them up.

The PrimaLuna amps are push-pull.
Push-pull is the circuit topology that REPLACED SET amps as the "modern tube amp design" (around the 1950's).
Compared to SET amps, push-pull tube amps are more like a modern amplifier.
Push-pull amps usually have much lower distortion overall than SET amps.
They start out at low power levels with much lower distortion (although still higher than a solid state amp).
Their distortion then increases more slowly as you turn them up until they approach clipping, then increases more suddenly once you pass clipping (which is more like how a solid state amp acts).
As long as you don't overdrive them, push-pull amps are much cleaner than SET amps, and sound less tubey.
(In terms of distortion, you could reasonably think of a push-pull amp as sort of halfway between a SET amp and a solid state amp.)

And, obviously, either one can be made in China (although, because they use somewhat expensive parts, non-Chinese-made SET amps tend to be very expensive).

I must also include a historical note here.........
The original tube amps were single ended triodes.
(And that included the cheap $5 amplifiers found in early portable phonographs.)
Pentodes are a slightly different sort of tube that offers slightly better performance than triodes (both triodes and pentodes can be used in either single-ended or push-pull configurations.)
When push-pull amps were invented, they offered much lower distortion, and higher efficiency, and were considered to be a HUGE improvement.
(In engineering terms, a SET amplifier delivers lower performance, using more expensive parts, than a push-pull amplifier.)

 

[gld3gld3]

Thanks kauai82 for relating your experience. It's helpful. From the advice I have gotten so far I think I am leaning towards waiting, saving some money, and purchasing used amp that is better made. I have looked at the PrimaLuna offerings. Those do look nice. As Keith pointed out, they are a different type of amp than the ones I'm inquiring about in this thread (SET amps). Not that I am against other topologies, but I am curious about the sound of low power SET amps in particular.

I understand your point, Keith, about the performance of SET tube amps vs. push-pull tube amps vs. solid state. I already have a perfectly good SS amp in the Mini-X. I'm looking for a different sound, so SET amps seem to be on the other end of the spectrum of amplifier design. I would expect the "performance" to be different than an SS amp. However, what I am looking for is a difference in the sound. Again, I'm keeping my SS amp and it serves me very well with my speakers. I won't get much better performance from another SS amp and I probably won't experience a very different sound with another SS amp either. My search for something "different" has thus far led me to SET amps, which I am most intrigued by. At the end of the day it's the experience I am after, not the specs or performance characteristics (although these are real and I understand their importance and what they can tell about amp). I have a SS amp to check those boxes.

My current thought is that I will look for a new or used amp in the $1000 or less range. One that I am particularly intrigued by at the moment is the Decware Zen Triode. Whatever I end up with I'm going to follow a lot of the advise I a have gotten here (thank you) and make sure I listen to the unit before I have to commit to buying (variety of options here, including an in-home trial period for internet direct companies) it and whatever I get will have good resale value (so I won't be stuck with a very heavy paperweight). 

Hopefully I will be able to make a decision and a purchase within the next year or so. It may be dependent on a work bonus! Haha! Hey, in the meantime I have a very competent and great sounding system to LISTEN TO MUSIC!

cheers everyone