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Old 29th January 2011, 06:44 AM   #1
jerryo is offline jerryo  Isle of Man
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Default 49.95 Tube amp?!

I have just seen this AD601 "Tube Amplifier" for sale on Ebay

Item number: 170596397070

Apparently there is a humm coming from the transformer so it is "B" stock.
Surely this cannot be a real tube amp! Is that a cooling fan vent at the back that I see?!
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Old 29th January 2011, 07:06 AM   #2
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It's a hybrid. The "real" amp is solid state (LM1875T) and the valves are used as cathode followers.
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Old 29th January 2011, 08:29 AM   #3
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It does make you wonder what those 2 6P15/EL84's are doing in that amp. They won't provide the 25Wpc this amp is supposed to deliver, so why are they there?
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Old 29th January 2011, 08:34 AM   #4
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Originally Posted by mastodon View Post
It does make you wonder what those 2 6P15/EL84's are doing in that amp. They won't provide the 25Wpc this amp is supposed to deliver, so why are they there?
Marketing hype...

If it glows, someone will probably pay over the odds for it.

Edit: I thought I'd seen something about these before on this forum... What do you think of this cheap tube amplifier?
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Last edited by Dragondreams; 29th January 2011 at 08:36 AM. Reason: More info.
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Old 29th January 2011, 08:39 AM   #5
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Well no LM1875 mentioned in the specification on eBay. Pictures look like there are OTs.
Anyway good single ended trafo costs much more then this amp.
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Old 29th January 2011, 08:48 AM   #6
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You'll probably find that underneath the box that looks like it should house OTs, there is a single toroid mains transformer...

Take a look at one of the other amps listed by the same vendor... the words "Hybrid" were added AFTER the vendor appeared on this forum to extol the virtues of the same amplifier. SAV-400A Vacuum Tube Integrated Power Amplifier 2X35W on eBay (end time 20-Feb-11 19:07:28 GMT)

The actual amplifier delivered (the SAV-400A) has no output transformers, no line out (as specified in the description) and on the whole was pretty shoddily made. I know because I bought one , albeit MUCH cheaper than the listed price. My own example has since had ALL the innards removed and replaced by a pair of point-to-point EF86 pre-amps. Even the "Real wood" description about the colour is misleading. The "real wood" is MDF...

So why did I buy it? Marketing hype and gulibility on my own part. I've since joined this forum and learned an awful lot more than I knew when I hit the "Buy it now" button... Hence my sig line.
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Last edited by Dragondreams; 29th January 2011 at 09:08 AM. Reason: More info.
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Old 29th January 2011, 09:27 AM   #7
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Quote:
If it glows, someone will probably pay over the odds for it.
That would be me.....
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Old 29th January 2011, 09:33 AM   #8
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That would be me.....


I reckoned the same when I bought the SAV-400. But it actually looks quite good (I'm in the process of replacing the MDF bits with German white oak). At the time, I rationalised that it wan't too bad a price to pay for a chassis if you want to junk the innards and build a real amp into it. Again, I've since discovered suppliers such as Bluebell Audio...
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Old 29th January 2011, 09:55 AM   #9
jerryo is offline jerryo  Isle of Man
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Hi,
it makes you wonder how many people have been caught out with this sort of thing. Does it break any "Trade Description" laws?
Dragondreams; I think you being generous with the notion that it is a toroidal tranny under the hood; I'll bet its just an EI
I wouldn't touch one with a barge pole although like you say it might be worth the money for the chassis and parts.
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Old 29th January 2011, 12:30 PM   #10
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I know because I bought one
Thank you for sharing your experience! This item is a very bad joke for buyers who not familiar with audio schematics especially.

I hate such kind of scum on eBay. I must admit that Audiogone a way better spot for purchase.

BTW LM1875 sounds excellent to my ears so it might be a good kit since you have already tubes in sockets and filament as well. It needs Just additional hi voltage trafo and two 6N1P could be combined as mu-follower for an input stage.
Might be sweet sounding hybrid amp eventually.
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