what about this website? http://stores.ebay.co.uk/Feedback-UpUpUp-99p-WinWinWin
Theses are the ones I was referring to.
Thanks btw
if you know of any good valve amp suppliers let me know please but I am not rich!
Theses are the ones I was referring to.
Thanks btw
if you know of any good valve amp suppliers let me know please but I am not rich!
hi I am afraid most chinese amps are poor,
1/ they have poor mains transformers, which are wound for 220 volts, and
2/ they have mostly poor output transformers that usually are small cored, lacking in henries for low bass, and sometimes an improper impedance ratio.
3. frequently, the capacitors and diodes in the psu are on limit and have a very short and eventful life.
4/ finally, some even have no safety earth, which in the Uk is a no no, if the case becomes live that's 450 volts. More advanced countries take safety very seriously, and rightly so.
Perhaps these chinese companies actually want to kill their customers.
5, also, they have manuals not written for westerners really, no information on servicing, biasing, all these may be wrong, 220 volts on your primary will give more volts on your tubes, perhaps stressing, shortening life, and even catastrophic failurers, however due to the probably low bias, this may be unlikely power wise.
They are flooding the market, I don't know how long they will last, they seem to think there is a lot of demand and cash to be made.
no doubt, some will go bust, a few will continue.
You have been warned, some are quite good tho'. Consonance, yarland and meixing are among the better ones.
You can get a good idea with both transistor and tube amps by the weight of the thing, more is always better.
As an aside, the dynavox vr 70, aka audio institute is unbeatable for uk £250 or so. Its well designed and doens't really have many bad points above.
http://cgi.ebay.co.uk/Roehrenversta...625689190QQcategoryZ35262QQrdZ1QQcmdZViewItem
as an aside, I know lim the seller below, personally, he will look after you and takes safety VERY seriously.
http://cgi.ebay.co.uk/Audio-Institu...oryZ3280QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
check here also..
http://www.apah69.dsl.pipex.com/dynavox/dynavox.htm
you can even buy 2, bridge it by paralleling the inputs and outputs, and have 80 watts of valves for £500. plentiful and cheap, too.
1/ they have poor mains transformers, which are wound for 220 volts, and
2/ they have mostly poor output transformers that usually are small cored, lacking in henries for low bass, and sometimes an improper impedance ratio.
3. frequently, the capacitors and diodes in the psu are on limit and have a very short and eventful life.
4/ finally, some even have no safety earth, which in the Uk is a no no, if the case becomes live that's 450 volts. More advanced countries take safety very seriously, and rightly so.
Perhaps these chinese companies actually want to kill their customers.
5, also, they have manuals not written for westerners really, no information on servicing, biasing, all these may be wrong, 220 volts on your primary will give more volts on your tubes, perhaps stressing, shortening life, and even catastrophic failurers, however due to the probably low bias, this may be unlikely power wise.
They are flooding the market, I don't know how long they will last, they seem to think there is a lot of demand and cash to be made.
no doubt, some will go bust, a few will continue.
You have been warned, some are quite good tho'. Consonance, yarland and meixing are among the better ones.
You can get a good idea with both transistor and tube amps by the weight of the thing, more is always better.
As an aside, the dynavox vr 70, aka audio institute is unbeatable for uk £250 or so. Its well designed and doens't really have many bad points above.
http://cgi.ebay.co.uk/Roehrenversta...625689190QQcategoryZ35262QQrdZ1QQcmdZViewItem
as an aside, I know lim the seller below, personally, he will look after you and takes safety VERY seriously.
http://cgi.ebay.co.uk/Audio-Institu...oryZ3280QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
check here also..
http://www.apah69.dsl.pipex.com/dynavox/dynavox.htm
you can even buy 2, bridge it by paralleling the inputs and outputs, and have 80 watts of valves for £500. plentiful and cheap, too.
With reference to the criticims leveraged against "Made in China" amps, I can only speak for the Music Angel EL34 Integrated Amp that I bought from the store above.
I, for one, am no fan of poor quality cheap labor crap but that amp I bought (which was intended for experimentation) definitely did not have any of the flaws mentioned in this thread. I requested for, and obtained a copy of the schematic (rather promptly). It is a hefy unit (heavier than a comparable ASL EL34) with good parts and build quality. I gotta admit I was surprised. The only snag is the poorly written manual but with some tech know-how and schematic at hand, my needs are covered.
So fortunately (or unfortunately for some), the Chinese are catching up. Do note that this particular eBay seller has detailed pictures of his products.
I bought a little valve headphone amp from China. Its called a Little Dot 2 and are always on ebay at USD95 plus USD45 shipping. It does use oddball tubes that you can really only get from the seller, but they're very cheap. Its not the best made amp in the world, but it has incredible sound........ just glorious. Just can't be beat for value and would hold its own against many higher priced amps.
I would not hesitate to deal chinese again, however, what you should do is contact some of the buyers on ebay who have bought the amp your interested in (check through his feedback) and ask them how they got on.....
Most sellers are reputable, but you don't want to meet the exception.
Fran
I would not hesitate to deal chinese again, however, what you should do is contact some of the buyers on ebay who have bought the amp your interested in (check through his feedback) and ask them how they got on.....
Most sellers are reputable, but you don't want to meet the exception.
Fran
reasonably priced quality valve amplifiers
I bought Icon audios LA-4 triode vacuum tube preamplifier ,with
all point to point Pure silver wire , heavy vishay 2 watt resisters,
Rubicon, and Solen capacitors,3 potted fine grain Japanese
transformers,Ceramic sockets ,even a remote with a automatic lower volume feature on it's own seperate board. And excellent sounding as in Julys Hifi news magazine stated with low distortion rating that were excellent by any standards. ,
a Superb special offer as a option with the superb very expensive Jensen copper coupling capacitors ,and 1950s NOS tubes for under
£1000 delivered . I can tell you this I have several freinds ,one with a AR 25 ,and sp16, and a Naim, mine is much more musical with superb soundstaging and punch and cool looking .I think it is still on special at hifidelityaudio.
I bought Icon audios LA-4 triode vacuum tube preamplifier ,with
all point to point Pure silver wire , heavy vishay 2 watt resisters,
Rubicon, and Solen capacitors,3 potted fine grain Japanese
transformers,Ceramic sockets ,even a remote with a automatic lower volume feature on it's own seperate board. And excellent sounding as in Julys Hifi news magazine stated with low distortion rating that were excellent by any standards. ,
a Superb special offer as a option with the superb very expensive Jensen copper coupling capacitors ,and 1950s NOS tubes for under
£1000 delivered . I can tell you this I have several freinds ,one with a AR 25 ,and sp16, and a Naim, mine is much more musical with superb soundstaging and punch and cool looking .I think it is still on special at hifidelityaudio.
woah
The http://cgi.ebay.co.uk/Audio-Institu...oryZ3280QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
Is the cheapest (quality wise) amp i've ever seen in my life. NICE!!!
The http://cgi.ebay.co.uk/Audio-Institu...oryZ3280QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
Is the cheapest (quality wise) amp i've ever seen in my life. NICE!!!
lgqliu said:
Cost.
For my money, if you plan to spend, say, €500 on a tube amp, I would get an old Leak (in Europe) or Eico (in America). The OTs on those alone would cost as much as a low-price Chinese tube amp if made today.
"The Eicos had an excellent output transformer. I didn't have much test equipment at the time but I did have a lamp stabilized oscillator, home brew, and an oscilloscope good enough for audio. I loaded one of the amplifiers and looked at the lissajou figure on the scope. At 50 watts it held a perfect streight line from 20 to 20,000 cycles. The Hammonds don't come close to doing that well. I wish I could find a couple of those transformers or maybe the whole amplifiers." --http://www.angelfire.com/electronic/funwithtubes/Amp-50_W_4_6L6.html
Dynavox VR70
Hi,
pleas have a look on my websites
I have tuned an Dynavox so that he has a better curve linearity
ther are not much things to
here is a link to ma homepage (sorry it's only in german)
the modifications are in blue in the cuircuit.
http://www.retro-optonica.de/Dynavox/DynavoxSchaltplan.htm
http://www.retro-optonica.de/Dynavox/Dynavox.htm
i hope you can understand what i have done.
Kind regards from Odenthal / Germany
Bierbauch2000
Hi,
pleas have a look on my websites
I have tuned an Dynavox so that he has a better curve linearity
ther are not much things to
here is a link to ma homepage (sorry it's only in german)
the modifications are in blue in the cuircuit.
http://www.retro-optonica.de/Dynavox/DynavoxSchaltplan.htm
http://www.retro-optonica.de/Dynavox/Dynavox.htm
i hope you can understand what i have done.
Kind regards from Odenthal / Germany
Bierbauch2000
No question they're getting better. Other than some communication problems the products I oem'd in China have been good quality and reliable.
Most do have proper grounding arrangements. (I really haven't seen any that didn't.) Most are a lot safer than some of the lousy lash ups I have seen DIY..
Designs range from quite good to very poor, pretty much as they did here in the heyday of tube audio.
Labor costs are low, components are locally sourced and usually inexpensive - but not necessarily inferior either.
Most companies are privately held and ran by people who have real passion for what they are doing. Working conditions probably aren't any worse than those enjoyed by people doing similar work here in the 1950's..
Well worth the risk I think..
Most do have proper grounding arrangements. (I really haven't seen any that didn't.) Most are a lot safer than some of the lousy lash ups I have seen DIY..
Designs range from quite good to very poor, pretty much as they did here in the heyday of tube audio.
Labor costs are low, components are locally sourced and usually inexpensive - but not necessarily inferior either.
Most companies are privately held and ran by people who have real passion for what they are doing. Working conditions probably aren't any worse than those enjoyed by people doing similar work here in the 1950's..
Well worth the risk I think..
I cannot recomend more highly and enthusiastically a sleeper offering by MingDa called MC34B. I had it's more expensive MC34A sibling (P-P 6CA7's, 30 watts/ch) here to compare the two amps and as supplied out of the sealed box this less expensive B version sounded better and had better soundstaging! MC34B comes rated at 22 watts ch. (The way I measure conservatively my figure was 18 W RMS/ch) from pairs of 6L6's in U/L. little tubes in front are 6N1 and 6N2.
After I had lived happily with my MingDa MC34B for a few months I decided to roll tubes to see if I could get any improvement. The amp responded very favourably to tube rolling. I ended up with the way I measure seeing 28 watts/ch RMS with both channels simultaneously driven to full power using fine vintage Mullard 2nd generation 6CA7's set at 35 mA each quiescent. At this load the B+ supply makes about 420 volts and the power xfmer does not get hot. I have run my amp 24 hours straight with no worries about it getting too warm (I run with the attractive tube dress cover removed for better cooling). There are pots hidden under the chassis to play with bias individually on each output tube if you wish. I ended up using a 6BK7B as the long tailed phase splitter and a 6CG7 as the line stage input. This amp is musical and stone dead quiet. No hiss, no hum.
If you like pounding rock and roll it has the power and command of the bass. If you like jazz it has the finesse..
Construction quality is excellent. Grounding is single point star. 3 wire grounded IEC power connector keeps things safe and the 4-8 ohm output binding posts are the sexiest, best quality binding posts I've ever seen on an amp. Tube sockets are all porcelain. Chassis is mirror finish stainless steel that will never rust pit like the Eico and McIntosh chassis. Styling is very attractive IMO.
As a bonus the MC34B has a switch on the side which swaps the speakers for dummy load resistors inside the chassis while activating the headphone jack.
This amp is a five star winner in my opinion and I cannot see myself ever parting with it.
Not counting shipping I've seen these available for as little as about $350.00 US from Hong Kong on ebay. A great deal if there ever was one!
After I had lived happily with my MingDa MC34B for a few months I decided to roll tubes to see if I could get any improvement. The amp responded very favourably to tube rolling. I ended up with the way I measure seeing 28 watts/ch RMS with both channels simultaneously driven to full power using fine vintage Mullard 2nd generation 6CA7's set at 35 mA each quiescent. At this load the B+ supply makes about 420 volts and the power xfmer does not get hot. I have run my amp 24 hours straight with no worries about it getting too warm (I run with the attractive tube dress cover removed for better cooling). There are pots hidden under the chassis to play with bias individually on each output tube if you wish. I ended up using a 6BK7B as the long tailed phase splitter and a 6CG7 as the line stage input. This amp is musical and stone dead quiet. No hiss, no hum.
If you like pounding rock and roll it has the power and command of the bass. If you like jazz it has the finesse..
Construction quality is excellent. Grounding is single point star. 3 wire grounded IEC power connector keeps things safe and the 4-8 ohm output binding posts are the sexiest, best quality binding posts I've ever seen on an amp. Tube sockets are all porcelain. Chassis is mirror finish stainless steel that will never rust pit like the Eico and McIntosh chassis. Styling is very attractive IMO.
As a bonus the MC34B has a switch on the side which swaps the speakers for dummy load resistors inside the chassis while activating the headphone jack.
This amp is a five star winner in my opinion and I cannot see myself ever parting with it.
Not counting shipping I've seen these available for as little as about $350.00 US from Hong Kong on ebay. A great deal if there ever was one!
CLS said:
This 300B driving 805's appears to be almost a direct copy of the MingDa MC3008AB of which I have one of the first production units (s/n 10). It had power supply issues which I fixed by replacing the entire power supply with a much improved model inside a larger custom enclosure of my own artistic design. I also went to great lengths to engineer a complete integrated cooling system. Those 805's dissipating 120 watts each as radiant heat really cooks the adjacent black transformer enclosure (which was not ventilated), and the acrylic top cover. The factory supplied output iron is generously sized and the audio circuit is well conceived. If the power supply has been improved this amp represents really good value retailing under $1,000.00 US.
Here is a picture of my custom work. 18 coats of piano black lacquer on a hard maple, copper lined box. The now about 130 lbs. beast is large and contains about 10 transformers including a large Hammond plate xfmer and choke input filter on the high B+ rail. Original HV supply was a C-R-C doubler circuit (that melted taking the power xfmer with it). My heavily modified amp has been in almost daily use for more than two years with no problems.
I love this amp so much I'm sure I'll never part with this unique personal DIY custom copy It has the SET magic I love and the power (40 watts RMS/ch) of a push-pull.
This is the first showing of this project on DIY forums. I was keeping it under wraps.
Attachments
Dynavox Ruru Twinsound
I look for the schematics of the Amplifiers CST-70 CST-80 CST-160
The manufacturer is a only Chinese Firm that rename with various
marks : Dynavox - Ruru ...
tnx !
I have found only this : http://www.mei-xing.com/English/e-gcjj.htm
I look for the schematics of the Amplifiers CST-70 CST-80 CST-160
The manufacturer is a only Chinese Firm that rename with various
marks : Dynavox - Ruru ...
tnx !
I have found only this : http://www.mei-xing.com/English/e-gcjj.htm
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