Mullard 5 10 Watt amplifier future build

[jcalvarez]

Nice touch with the VU meters

Thanks, they are more of a gimmick, but look nice especially in the dark 🙂

 

[Steve Morley]

If you want UK parts try these: https://primarywindings.com/product/mullard-5-10-el84-10w-output-transformer/ They also have power trans too. Not used them so can't comment. Other SPP builders have used Toridy form Poland with good results. https://www.tme.eu/en/details/ttg-el84pp/toroidal-transformers/toroidy/

A couple of different SPP builds on this forum and on the Tubelab forum. https://www.diyaudio.com/community/threads/easy-diy-tube-amp.384618/

S.

 

[calpe]

I would like to try and keep suppliers down as much as possible.
https://www.rapidonline.com/ seems to be a good choice to start with.
The 2x 1650HA + 1x 372JX are what? From where did you order them? £374 for just three items, is quite a chunk!

 

[calpe]

Are there a workshop in the area where you live? Make a drawing and ask the workshop how muck it costs to make a chassie? I like to build with aluminium. That because it is easy to work on, easy to drill holes in, etc. My amp chassie got aluminium with 1,5-2mm thickness. Start to make a plan over the parts you will need...capacitors, resistors, transformers, and so on. There are a lot of people out there who sells components, and many of us have to much lying around, and will sell/give away for "nothing". Where are you living? Find the right schematic on the intrnet. Look around you, use standard capacitors and resistors. Do not buy cheepish transformers, I am a fan of Hammond and use a 370HX and 1650E for output transformers, and chokes for the power supply. The chassie are 41cm x 29cm x 8cm, (w-d-h) and I think I found it near a trash-can? Probably have been a power supply, or something used in the PC-world? Just look around? Good Luck, https://www.diyaudio.com/community/threads/made-myself-a-el84-pp-tubelab-clone.381104/

Stenak, there are workshops near me, but it'll probably be cheaper to buy one

 

[calpe]

One last post and i'll leave this thread.

From recommendations, I'll probably move over now to Tubelab Simple PP and check things out..
Thanks to you all.

 

[stenak]

One last post and i'll leave this thread.

From recommendations, I'll probably move over now to Tubelab Simple PP and check things out..
Thanks to you all.

Buy the Tubelab PCB, og solder point to point.

 

[jcalvarez]

I would like to try and keep suppliers down as much as possible.
https://www.rapidonline.com/ seems to be a good choice to start with.
The 2x 1650HA + 1x 372JX are what? From where did you order them? £374 for just three items, is quite a chunk!

Transformers are the most expensive bits. I ordered them form Digikey.co.uk.
1650HA-> Hammond 40W push-pull output transformers 6600:8, a couple for a stereo amp. I wanted to use 6L6 tubes hence the choice of impedance.
372JX-> Hammond power transformer.

It was my first build, so I went for things that I was 100% sure would work fine, based on what I read here. These days I would not buy a power transformer, I'd use an SMPS.
Output transformers are always expensive, but if you do not need a lot of power then you should be able to get a decent pair for £100

 

[Steve Morley]

Calpe,

If you are building an EL84 amp the 1650HA is more transformer than you need. The 1650F or 1650FA works just fine with EL84s. For power the 372JX is fine if you are using a tube rectifier. If going the solid state rect. route a 370HX would be a better choice so the B+ doesn't get out of hand.

S.

 

[jcalvarez]

Calpe,

If you are building an EL84 amp the 1650HA is more transformer than you need. The 1650F or 1650FA works just fine with EL84s. For power the 372JX is fine if you are using a tube rectifier. If going the solid state rect. route a 370HX would be a better choice so the B+ doesn't get out of hand.

S.

The 372JX is also an overkill for an EL84 amp, 243VA.

 

[ejp]

You don't need a 40W output transformer for a 10W amplifier. Save your money.

 

[jcalvarez]

You don't need a 40W output transformer for a 10W amplifier. Save your money.

I did not suggest using those, I merely stated what I used in my amp.

 

[ejp]

Well if yours isn't a Mullard 5-10 I don't know what it's doing in this thread.

 

[jcalvarez]

Well if yours isn't a Mullard 5-10 I don't know what it's doing in this thread.

See #13. It started with a question about where to buy what.
let's not go into useless arguments.

 

[ejp]

I agree. Let's not. This thread is about a 10W amplifier. Let's not have useless contributions about where or even whether to buy 40W transformers.

 

[calpe]

End of the thread please. And thanks to you all.

I've decided to build the http://tubelab.com/designs/tubelab-spp/ so i'll probably start a thread based on it.

Please no more posts.