Musical Paradise MP301 MKIII: Output Transformer Shootout!

[@RobTukham]

I just wanted to thank you for making these videos. Obviously a lot of time and effort is involved in making these quality videos.

[@cobar5342]

Thank you Stephe. Output transformers has been a difficult subject for me. This helps a lot

[@junkmangeorge6363]

They are a difficult topic for everyone. Good ones are expensive, sometimes there is an unexpected surprise of good ones in a cheap stereo, but not often, and not in this Musical Paradise turd.

[@paulgood2218]

Thank you for another fun video!

[@g-train9372]

Hope you enjoy your well earned break Steph!

[@nevillegoddard4966]

Very interesting video! Clearly shows the performance compromises we get between o/p power vs. o/p distortion, as you vary the opt's i/p impedance (as long as we don't get confused by all the acronyms! hehe!). Also obvious are the improvements gained by using higher quality opt's, like those blue edcores - quite significant! I would also have liked to have seen the performance of the Iso-tango opt's as well! But of course, I understand that you'd eventually go crossed-eyed & stir crazy from all the soldering & desoldering of transformer wiring! We don't want you you blowing bubbles in your soup! Thanks for your effort Stephe!

[@SkunkieDesignsElectronics]

Getting close :P

[@jukingeo]

@Skunkie VERY interesting results with your testing! It did go inline with my thoughts and I had figured that with the enclosed transformer from Edcor that you would get a jump in performance. I was very curious about the open core transformer, but when you mentioned that transformer was more for guitar amplifiers, my hopes were a bit dashed and your tests confirmed that. Further, I am lead to believe that the original transformers in the amp were probably meant for guitar amps given that the performance between those and the open core Edcors were similar. So, yeah, I agree that it would be best to stick with the original transformers and just do the mods to the amp. I would say that if I could get the amp for around $350 to $375, then I would go for it myself. But lately I have seen it between $425 and $550 and that is a bit much. Great video and thanks for sharing the test results!

[@junkmangeorge6363]

"Usable quality" (not the "best quality") output transformers run me $165 each (+tax and shipping) here. This is why the Reisong A-10/A-20 is your best buy in this price segment, they come with "usable quality" output transformers. To me it's a "no-brainer".

[@rkoonce53]

Interesting comparisons. I would have loved to see how the ISO iron would compare. The ones I have provide excellent bass response.

[@rickg8015]

Hi Stephe.. I know your feelings about Parafeed (band-aid..), but in this case it might be worth a try, if you are ever you get curious.. If you could measure the stock OPT inductance the parafeed film cap value ballpark calc usually gives good results.. Regards.

[@tullskull]

Thank you Steph for all the work you put into these projects. I was wondering if you have any experience with Lundahl from Sweden? Have heard nothing but positive remarks but they are expensive.

[@SkunkieDesignsElectronics]

Not yet! I have heard they are good.

[@PossibleAudio]

Really interesting. Thanks!

[@OTO_45]

Great stuff and analytics. Please try the Tango for the final video. Cheers Stefan

[@SkunkieDesignsElectronics]

That's for another video, there is no way this amp could use those.

[@g-train9372]

Awesome Steph. You could hang the opt’s out the side and make it look like a flat 4 / VW boxer engine. Or lose the handles. Put on some 1 inch thick or more side cheeks and top mount the transformers beside the mains transformer??

[@SkunkieDesignsElectronics]

Those are options for people who want to do that far with a mod. The other option would be to put the guts into a larger chassis?

[@NickP333]

⁠@@SkunkieDesignsElectronicsOr hang new OPT’s with an elastic type of material from a jig made of old erector set pieces that sits above the amp to make absolutely sure no resonances make it back to the amp chassis. 🤷‍♂️ lol

[@g-train9372]

Would 12 watt 5 k opt be suitable? Silk from SAC Thailand have fairly well regarded transformers at a pretty comparable price to Edcor. They don’t seem to have 15 watt units though.

[@g-train9372]

@@NickP333 you could be on to something….

[@SkunkieDesignsElectronics]

12W would be plenty, I use 12W ISO Tango on my EL34

[@mfr58]

They may have used smaller caps to limit the low end to reduce saturation and distortion a full range would produce in those rubbish x'frmrs....I think if I had one of these amps, I would make a separate chassis for the power supply and mount the good quality x'frmrs on a plate where the power x'frmr was.....

[@williammeincke9071]

Hi, im trying to watch almost all your vids since i want to get to a point where i can build my own tube amps. I found it quite funny how much u think power cables are snake oil, they are defintely overpriced very often. I with my own ears hear a clear difference between power cables and they can be diyed way cheaper aswell.

[@SkunkieDesignsElectronics]

Go for it!

[@davegrant9179]

I agree,. What's the best way to DIY the cables?

[@junkmangeorge6363]

If you must, go to a local thrift shop and buy a "electric kettle cord", with the appropriate ends, if you want a heavy power cord. (I don't hear any difference).

[@williammeincke9071]

@@junkmangeorge6363 if you dont know the properties of a cable you are comparing there is no point many cables sound the same. In my experience wire thickness changes sound try comparing 10 guage and 22 guage. Or a pure cobber vs pure silver very noticable differnce for me

[@junkmangeorge6363]

@@williammeincke9071 Just stop your foolishness.

[@peterweinberg4504]

Looking at the pictures and dimensions, the GXSE 15-8-5k might just fit.

[@SkunkieDesignsElectronics]

Mounting them is gonna be the challenge

[@adamfrandsen]

what a difference

[@sajyho1988]

IMO if you want to really test the OPT alone and not the amp, you should use a low distortion Cl. AB amp and connect it to OPT's secondary through a power resistor equal to nominal secondary load, and then load the primary with resistance equal to the tube's plate resistance.

[@SkunkieDesignsElectronics]

Did you read the title of the video?

[@sajyho1988]

@@SkunkieDesignsElectronics Oh now I get ot 👍👍

[@elcocineroamericano]

I think we can already guess the outcome but it would be really interesting to see a comparison with those $27 AliExpress trafos. I mean, how bad can they be? Show us, Stephe!

[@SkunkieDesignsElectronics]

send me some :)

[@hugobloemers4425]

Hi Stephe, this is a very interesting video. Finding the right OPT is not easy and this is helpful. Would you put a 7K OPT if you where to build an EL84 amp? (Based on the 3.5K versus 5K choice for the EL34)

[@SkunkieDesignsElectronics]

It depends on the operating point, the % of UL tap and... testing.

[@mr1enrollment]

curious about the app, where do you find it?

[@SkunkieDesignsElectronics]

kzbin.info/www/bejne/baq7hpWLaseGfdk

[@drdyna]

If it was mine I'd probably just bolt the new trafos on the sides ala Frankenstein lol

[@NickP333]

I’m not able to except gear that knowingly uses cheap parts to meet a price point. I fully understand why it’s done, but I’ve gotta wonder how much of it is just bad design work, not caring, and / or knowingly putting out a product that “works” enough to make a sound. They all seem to kinda be somewhat intertwined. I’d like to think that at least a few of these companies started out with good intentions, thinking positively about their new product, instead of, “those suckers will buy anything”. I’ll stop there….

[@NickP333]

Ya know what, I swear I’ve got a matched pair of JJ 6L6’s from Apex Audio somewhere. I don’t really have much of a use for them, so I’ll send em your way if you want em.

[@SkunkieDesignsElectronics]

And I have to think there was a prototype at some point that performed well, it was sent to China for "reproduction" and this is the result. Could be some parts were swapped out at some point in the production run without their knowledge? Or maybe not, I have no idea. Several people were trying to get me to do this with one of my amps, but I knew "the magic" would disappear. This same person had a product manufactured in China, and said the folks he was dealing with would endlessly try to swap in cheaper parts or cut corners, he was having to check every unit and was sending over 50% of them back. Life is too short to get involved with something like that.

[@nevillegoddard4966]

​@@SkunkieDesignsElectronics Argh! They really do that? - sneak in cheap-ass parts when you're not looking? Damn termites that's awful!

[@debilthomes501]

People should read the book “Poorly Made In China” by Paul Midler. It does not focus on electronics but gives a good idea of what it’s like to have your products made in China.

[@SkunkieDesignsElectronics]

From what I understand, it's a point of pride to see what you can get away with as a businessman.