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greenie512
8th September 2007, 12:48 PM
Just like those of you who insist on doing everything with hand tools (I’m just envious) … I have always though those that swear by valve amps are definitely on the Dark-side.

Well, we had a Brisbane Speakers Builders meet last weekend .. see http://www.diyaudio.com/forums/showthread.php?s=&threadid=107876&perpage=25&pagenumber=1 if you are interested.

One of the major outcomes was for those like me who’d never played with valve amps, just how good these “cheap” Chinese amps were – well at least the one we tried. I was sorely temped to buy the valve amp we tried– it was that good. However I’m sure buyers-remorse would have kicked in if it had been the first and only valve amp I’d listened to. John a mate and importer of these Chinese Ming Da amps says the MC368-B90’s tubes provide more “grunt” and are more “masculine” than normal tubes and he suggested trying the MC3008-AB for a more traditional valve sound.

B**gger me; the thing weighs in at 28+ kg I nearly knackered myself getting that thing out of the boot of the car. Obviously, the tubes need to burn in so initial impressions could be misleading but once I’d fitted the four rear monster tubes this amp sounded good from the off.

Now I’d bought Musical Fidelity amps as my “final” purchase for amps 7-8 years ago. I recon that at this level we’ve hit the top of the steep curve and it’s all the very shallow up of diminishing returns part of the graph – that says the more money you through at hardware the less you get back in sound quality!

So I was really stunned at how good these “cheap” valve amps, can sound. Are the hugely better than the MF’s – no, but they are as good and they pull out more subtle sounds. So instead of just hearing the reverb in a hall on a live recording you get the multiple reverbs off walls further away. On the “Norma Waterson” CD you know Eliza (her daughter) is singing backing but with the valves you can hear her different inflections in the background.

The MC3008-AB costs more and I’m sure a lot of people would go for the MC368-B90 as the more up front sounding amp, the bass certainly was tighter. But I like the MC3008-AB for the same reasons I bought the MF’s - I find a lot of amps initially very good but ultimately hard and tiring to listening to.

Still have the rest of today and Sunday to make up my mind – but you can see what’s coming. If I do buy I’ll probably sell the MF X-P100 preamp and X-AS100 amps (2 of) on eBay and probably break even on the purchase or even make a little. However the second-hand value of Chinese valve amps will be pretty weak if I ever sell this one.

And in the future I can look forward to tube-rolling and adjusting the sound with different valve (at a cost).

greenie512
8th September 2007, 01:02 PM
One thing I forgot to say is these mosters generate a large amount of heat and the MC3008-AB is a class A amp which produces even more heat.

Although there is a "grille" cover this is only a push-on fix so a kid could pull it off. The HUGE transformer at the back isn't covered and it gets really hot to the touch.

The good side to this is I now have a hot plate to keep my take-aways warm. The other down side is I'll need more air conditioning in summer???

kiwigeo
8th September 2007, 07:45 PM
Reminds me of a NZ made Gunn 200 watt amp I used to run my bass through. At times the thing would get hot enough to fry and egg on top.

martink
21st September 2007, 01:21 AM
One thing I forgot to say is these mosters generate a large amount of heat and the MC3008-AB is a class A amp which produces even more heat.

Although there is a "grille" cover this is only a push-on fix so a kid could pull it off. The HUGE transformer at the back isn't covered and it gets really hot to the touch.

The good side to this is I now have a hot plate to keep my take-aways warm. The other down side is I'll need more air conditioning in summer???

Ah yes, people seem to forget that valves once powered everything - I remember when I studied these animals at TAFE! As far as these buggers getting all hot, remember the term, "Wait for the TV/Radio/Whatever to warm up" ? I remember this, but was never too sure if Mum just wanted me to tell her when it was good and hot so she could cook the fish fingers:o

Ciao,

M.