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Cheap ($235) SE Tube amp kit, transformer and chassis on ebay

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...and the schematic

That was quite quick! FYI I'm not associated with the seller in any way, I'm just looking to get informed feedback before I consider a purchace.
 

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depends what you are looking for.
you could try the oatley elec kits (also not affiliated with them - the k281) if you are like me and looking for a bit of experience.
oatley are also up nth in NSW so local(ish) to us. also is a smaller investment. depends what you want

cheers mate
 
Hi all,
Saw this HIFI Audio Tube Amplifier SE EL34B Amp DIY Kit Stereo | eBay recently online and wondered if anyone had built it. The cost is pretty reasonable (US$235) as is postage to get it to me.

I've queried the seller and I'm waiting on a copy of the schematic, but whilst I wait, any thoughts?
That's 235$ + 90$ shipping = 325$ ... But it is a good price ...

Suppose you build it yourself not with a kit :

If you buy all those Shuguang tubes brand new on eBay, you will paid about 80$
If you buy the transformers from Edcor, you will paid about 170$
Figure out 10$ for the sockets, 20$ for the frame, 20$ for the volume pot, 10$ for the plugs, 30$ for all the resistors and good capacitors, 20$ for different hardware ...

All that cost about 360$, maybe a little less ...

Cheers,

Alain. ;).
 
Hi,

From the cct diagram, it appears the EL34E is triode connected, hence lower output power, I don't think you can get 10W from each channel. the o/p transformer is not an ultra-linear one so you cannot modified the cct diagram to operate in ultra-linear mode, in this mode you can get about 12Watts.

If you are interested in this type of amp try this site:Shuguang,Shuguang treasure,Fullmusic,Guiguang tubes,amplifier chassis,tube sockets,capacitor,resistors,coil meters,toggle switches,tag boards,transformer covers,various parts for tube guitar amps diy <meta name="keywords" content="tube sockets,shugua

look under vacuum tube amplifier heading, model GDAP 01. I bought a unit. the o/p transformer is ultra-linear type. For the money I am quite happy with it but it is not operating in its ideal state, I have to modify it to apply operate feedback to the cct.

BTW I am not associated with the company.
 
That was quite quick! FYI I'm not associated with the seller in any way, I'm just looking to get informed feedback before I consider a purchace.
That is the circuit ...

With a 340 ohms cathode resistor, the bias most be very high and there will be more than 10% distortion at full power for sure ... And there is no feedback to attenuate it ...

I also notice the voltage of the screen grid is higher than the plate voltage because the voltage drop in the primary of the output transformer ... It suppose to be equal or lower ...

All that is a bit suspicious but you can modify it to get a better sound, but less power. The 6CA7 / EL34 have a separate suppressor grid from the cathode, it can be reliate to the screen grid and plate to make "a real triode connexion" ... The power will be much less but the distortion too.

Cheers,

Alain. :)
 
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Cheers for the input everyone

...I reckon I'll give that a miss then. I was mainly attracted to the full kit, as my failing is often in completing the chassis, hence a complete kit was pretty appealing. Given the constraints of getting decent performance out of it I reckon I'll be better off spending elsewhere. Shame though!

Cheers for the input everyone.
 
My main concern with these kits is the quality of the output and power transformers. Those are the more expensive components, hence, the most obvious place to cut corners in order to offer a "cost effective" (read: cheap) product.

The Edcor OPTs are pretty decent. Not top of the line, but real good bang for the buck.

There are chassis options that don't require too much machining. They're not at scrap metal prices, but for the machining required, they're actually not bad... Check out Audio Catalog for example.

~Tom
 
I went "partial" kit for my first amp...the Tubelab SimpleSE. Started with the PCB and bill of materials and LOTS of support here.

I started on the cheap with inexpensive iron, non-exotic resistors and caps and probably had only like $250-$275USD into it.

Since then I have upgraded certain components - better iron, better coupling caps, and decent tubes.

There are some great P2P amps that would be a great starting place like Mikael Abdella's KT88(spelling?) A super simple SE amp that would be a breeze to P2P up and has good reviews here and other DIY forums.

I highly recommend edcor iron. Lead time is a pain but well worth it for the price. For this type of SE amp I would really recommend the GXSE's and a PT that could handle at least 150-175mA.
 
That was quite quick! FYI I'm not associated with the seller in any way, I'm just looking to get informed feedback before I consider a purchace.

It is a good deal or not depending on the quality of the parts. If they are generic Chinese parts then the price is to high. If the parts are Hammond, JJ, Belton and so on then it's a good deal.

A assume no one builds a tube stereo amp because they want to save money. It's because we want an amp that we can't buy. If that is the case why use cheap parts? The most important part of an amp like this is the output transformer. What one are they using? Do you like the way it sounds? If you don't know the answers then why get this one?
 
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