YAQIN MC-84L and the Pioneer SP-BS41-LR 130W speaker help needed

I wouldn't do this. If you want to stay with tubes, get amp with kt88 power tubes. It would be more appropriate. It will give you 35-40 watts, with some safe overload margin. You can try both 4 and 8 ohm taps, and choose one that is better. This is very dependent on amplifier design.

There is nothing wrong with that setup, except that it is not going to play very loud.

You are certainly not going to damage anything. Try it and see how it sounds.

I should say, however, that the Pioneer speakers are a very poor match for such a low-powered amplifier, with a very low sensitivity of only 85 db per watt. That seriously compromises your setup and puts a heavy load on the amplifier needlessly.

A speaker with a higher sensitivity, 90db per watt or higher, would be a much better choice, giving your system a lot more headroom and allowing the amplifier to do a better job.

I would stay with your amplifier and get some speakers that are more appropriate for it.

You won't be able to reach synergy between the speaker and the amp. That synergy should be a goal when you buy multiple components. Also there are different definition of what constitutes "small" room. For us here in US this is anything less than 20 sq. meters. If you plan to sit closer that 2 meters to speakers, get specialized near field monitors designed for professional use. Regular hi-fi speakers need enough distance to provide balanced sound.

My first choice for that would be the Audio Research VSi60.

The Vincent SV-236MK is a hybrid design that is very good.

All of the Primaluna amplifiers are also good; I would recommend the Prologue Two Integrated amplifier.

You should choose one with at least 40 watts per channel for those speakers.

The Musical Fidelity M3i is excellent, but that is solid-state.

The Yaquin MC100B apparently puts out 60 watts per channel in ultralinear made, so that might be an option.

fwiw, don't know what your budget is but from $300-$600 range i would look into these amps these have enough power to push your speakers can get these on ebay through canadian hifi online store. the owner Song is really great with any questions and service is great.

yaqin vk-2100 hybrid $299+ ship.

yaqin mc-10L $449+ ship.

yaqin mc-13s $549+ship.

yaqin ms-20L $549+ship.

Whet you are talking about Yaqin, cut specified power in half. That will be real number.

I see you bash Yaqin every chance you get.
Because one test you did on one model amp gave lower than rated #s.
I ask that you stop. Because if you did research you would see pretty much every other site that a use has it they have gotten either the wattage they were suppose to or very close.

Yaqin puts out rated power.

How did you test the one you even checked? Clamp? Scope?

I do not bash anything. Yaqin has its place in the affordable end of tube amps. I only hate when someone declares inflated specs which confuses customers.

I did extensive measurements of MC-100B using spectrum analyzer software. I even modded my unit slightly and was able to reduce distortion quite a bit. I posted my results on two other forums (they were too technical for this one) and you can find them though Google search.
Edited by ap1 - 6/15/12 at 7:35am

Out of curiosity I read the threads on the other forums and found them interesting for a number of reasons, but I would have preferred to see the actual measurements, rather than some typed numbers.

At the end of the three part thread, you mentioned rebuilding it. I'd suggest leaving it as is, or returning it to stock and selling it and simply starting from scratch. A chassis is a piece of cake to make and will allow more flexibility, for example in using transformers with a different form factor. Plus, there's very little in the circuit originally that I'd reproduce, especially the input stage and not needing to use tubes you can source in commercial quantities new, there are many better options available to the DIYer. You'll also not find it hard to better the Chinese iron, especially the OPTs as every single unit that has been across my bench has been mediocre at best with obviously non-sectioned windings and PTs that have not given their rated current with good regulation and/or ran hot.
Keep the KT88's though.

Unfortunately I didn't make screenshots while I was working on it. I made notes all the way through, that is why I had to type numbers. I will try make them next time I will work on it.

My goal was to see what is the main limitation of this Chinese amp. It seems that transformers are. Good thing is that I can use different ones, as soon as they fit within cans (which are quite large), even if size is somewhat different. Unfortunately I am not very good in metal work to make nice looking chassis myself, and ordering one to be custom made is very expensive here.

Excellent, thanks. Not to mention the topology and tube choices (at least in part). if you build it in the traditional 'picture frame' format, then you have a 4 sided box that is very easy to make. Then add an aluminium top and bottom plate. These can be ordered through any place that does laser or water cutting of metal, very cheaply and local to you. My last one cost about $70 IIRC and the wood I already had, but still, no more than $100 total, and no doubt cheaper in the US. The attachment shows a Supratek I googled at random, but shows the general idea. Par metal do some all Al units too for decent money.



Add good iron from Lundahl, Electra-print etc and a good topology and you could probably build it complete for less than the $1k and you could get a good chunk of the Yaqin purchase price back if sold stock. There are so many detail improvements I would make to the MC100 even if I kept the basic topology and iron, that I wouldn't be able to use the stock case. I'm not much into trying to make silk purses out of sows ears, when I can simply make the purse in the first place.