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Old 19th December 2010, 12:32 AM   #1
Haz is offline Haz  United Kingdom
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Default What do you think of this cheap tube amplifier?

Iv'e found this tube amplifier on ebay and I would like some honest comments about it.

The SAV-400A as its called its not really a tube amplifier as it uses power transistors instead of output transformers so I guess that makes it a hybrid amplifier?

There's a site I have found that gives more info about it, but this model has a better power output so its not the same model just the one above.

I know its not much to go on but some people should have experience of this type of thing.

Oh and one last thing I've already bought one for the price of 69.99!! should have been 379.99 yeah right!!

Link to the amplifier:
SAV-400A Vacuum Tube Integrated Power Amplifier 69.99 on eBay (end time 20-Dec-10 19:33:03 GMT)

Link to the web page: (in Chinese needs translating)
졿 AV-400A ӹܵ ؼ۴-Ա ҵ ׹

Thank you for any help you can provide me on this matter
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Old 19th December 2010, 12:35 AM   #2
6L6 is offline 6L6  United States
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It certainly is interesting!
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Old 19th December 2010, 12:41 AM   #3
Haz is offline Haz  United Kingdom
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That's why I bought it I found it very interesting.
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Old 19th December 2010, 12:53 AM   #4
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I can't quite figure out why they used two rectifier tubes, other than for appearances? I can't imagine they're using vacuum tube rectification for the solid state output stage. You wouldn't be able to pull enough current through the vacuum tubes. Are they using two vacuum tubes to make a full wave bridge rectifier? Cute, but wouldn't a center tap on the PT secondary be a whole lot easier and cheaper?

Isn't the 6N2 a small signal tube? I believe it's got rather a lot in common with a 12AX7. In the power supply department, I'd think a single 5Z4 would be overkill for just two 6N2. Two of them just seems silly.

Now I want to see a schematic for this strange animal.
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Old 19th December 2010, 01:53 AM   #5
TheGimp is offline TheGimp  United States
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And why UL SE transformers? Unless they are using FETs in the outputs.
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Old 19th December 2010, 02:45 AM   #6
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This looks interesting too.... too bad there is no N. American version affordable and available. AD-601 Vacuum Tube Integrated Power Amplifier 2X35W RMS on eBay (end time 12-Jan-11 21:18:37 GMT)
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Old 19th December 2010, 02:51 AM   #7
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Quote:
Originally Posted by Rockmore View Post
This looks interesting too....
At least it has some power tubes in it, even if the ratings are obscenely overstated. 35 watts a side from single ended 6P15? Maybe not. And why the heck do all these Chinese amps need to have a small chassis fan?

Last edited by Ty_Bower; 19th December 2010 at 02:53 AM.
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Old 19th December 2010, 05:15 AM   #8
lowpoke is offline lowpoke  Australia
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So Haz, have you received it yet? If so tell us what it sounds like!
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Old 19th December 2010, 10:59 AM   #9
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Hi,
IT's a fake bake (see the feedback) there ain't no power tubes.
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Old 19th December 2010, 11:21 AM   #10
AJT is offline AJT  Philippines
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Quote:
Originally Posted by Haz View Post
Iv'e found this tube amplifier on ebay and I would like some honest comments about it.

The SAV-400A as its called its not really a tube amplifier as it uses power transistors instead of output transformers so I guess that makes it a hybrid amplifier?

There's a site I have found that gives more info about it, but this model has a better power output so its not the same model just the one above.

I know its not much to go on but some people should have experience of this type of thing.

Oh and one last thing I've already bought one for the price of 69.99!! should have been 379.99 yeah right!!

Link to the amplifier:
SAV-400A Vacuum Tube Integrated Power Amplifier 69.99 on eBay (end time 20-Dec-10 19:33:03 GMT)

Link to the web page: (in Chinese needs translating)
졿 AV-400A ӹܵ ؼ۴-Ա ҵ ׹

Thank you for any help you can provide me on this matter


the SAV-400 sells as Sakua-200 in the Philippines.....i have analysed the circuit and the 2 rectifier tubes are used to supply +/-6 volts rails to a 4558 op-amp driving the tone control stack, the 2 6N23 tubes are cathode followers, mind you only 1/2 of each tube is used...rails for the cathode follower is +/-12 volts......

i have since exorcised the 2 5Z4 rectifers and is seriously considering removing the 6N23 tubes to be used in another project....

this is the scheme showing the recitifers:
Click the image to open in full size.

yes, this amp can run all solid state.....
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Last edited by AJT; 19th December 2010 at 11:28 AM.
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