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Modulus-686: 380W (4Ω); 220W (8Ω) Balanced Composite Power Amp with extremely low THD

They couldn't get you a replacement instead of a refund?

Had to get AliExpress involved as the seller was insistent it had been delivered. The tracking number they gave me showed the item never left China and the seller claimed they had inputed the wrong tracking number. The 'new' tracking number they gave to AliExpress was for an item delivered and signed for in London - I live 400 miles from London.
Got a refund from AliExpress who found in my favour (haven't got it yet, still being processed), didn't get the option of having a replacement sent.
Think I'll just stick to buying from Modushop, bought from them several times before with no issues. All the freight charges from China seem to have increased by about 50% in the past 2 or 3 months which makes it no cheaper to buy from China than Modushop once you add on the duty charges and handling fee from China.
Pity though as that was a nice case, pre-drilled rear panel and 150mm high so almost on a par with a 4U from modushop.
 
Where did you get the transformer mounting plates, I like them. edit Ah, found them on Toroidy, can't see how to buy them separately though, looks like they are only available with the supreme audio transformers. Also, what case did you use?
I had ordered one of these from China but it appears to have got lost on it's way to me and the price is now £40 more than when I ordered so looks like I'll be getting one from Modushop instead, pity as it's a nice case.
My case was the Deluxe 4U Aluminum ( DIYDX-4U300-A ) Modushop

Probably would go for the base version of this and customise the back/front panels, if I was to do again.
 
I'm pretty sure the "mounting plates" for the transformers is an option when you order. It's not a separate item. I bet it's secured to the transformer with the potting compound.

Tom

You have to order the mounting plates with it, and it comes supplied as separates with a large bolt.

The wiring loom makes this more of a necessity than option, (for me anyway).
 

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Had to get AliExpress involved as the seller was insistent it had been delivered. The tracking number they gave me showed the item never left China and the seller claimed they had inputed the wrong tracking number. The 'new' tracking number they gave to AliExpress was for an item delivered and signed for in London - I live 400 miles from London.
Got a refund from AliExpress who found in my favour (haven't got it yet, still being processed), didn't get the option of having a replacement sent.
Think I'll just stick to buying from Modushop, bought from them several times before with no issues. All the freight charges from China seem to have increased by about 50% in the past 2 or 3 months which makes it no cheaper to buy from China than Modushop once you add on the duty charges and handling fee from China.
Pity though as that was a nice case, pre-drilled rear panel and 150mm high so almost on a par with a 4U from modushop.
Same happened to me from Aliexpress

Ordered a case and waited a month for its tracking status to get stuck in Singapore.

Opened a dispute and the seller asked me to cancel it as it was still under protection. I left it two weeks and opened a dispute again as it hadn't moved and was now showing as delivered!

Aliexpress has paid up for the refund though.

Never had a problem before and I've ordered loads of cases from there.
 
Trying to order parts and the heatsinks for the Power 686, WA-T247-101E, are on back order at Mouser, RS, Farnell, Digi-key til November :eek: Is there an alternative anyone has used?

edit .... just found WV-T247-101E is in stock, it's the plain aluminium version, non-anodised. That'll do, phew!
 
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Trying to order parts and the heatsinks for the Power 686, WA-T247-101E, are on back order at Mouser, RS, Farnell, Digi-key til November :eek: Is there an alternative anyone has used?

I have four of them on my desk. I bought the last eight available in North America not long ago. At the time Newark still showed stock in the UK.

edit .... just found WV-T247-101E is in stock, it's the plain aluminium version, non-anodised. That'll do, phew!

That is absolutely epic. Thank you for following up. I'll include that P/N in the design doc.

Mouser shows 3200 in stock. You think that'll cover your needs? :D

Tom
 
Inventory Search - Ohmite Mfg Co

Problem is that the MOQ is large (30 to 200 off depending on source)

But the thermal performance of a heatsink is only weakly dependent on the colour. They work mainly by convection. So the anodized version is 11C/W and the plain aluminium is 12C/W. Anodizing is cosmetic only - which is why some heatsinks are anodized in funky colours like blue or red (or even gold plated).

Craig
 
Still work in progress, but now have the links working on my photo blog of my
686 Modulus build experience. 12 pages of build/test process pics. These may or may not help future builders. :)

Neurochrome 686 – The Build – Andy T's Techno Blog

Special thanks go to Tom, for the design of the boards and also for the tech support diagnosis, when I smoked some caps.:eek:

Andy

Great build Andy!

I just wish the 90 degrees LM3886 was still available so we wouldn't need to do it manually but there's nothing a little DIY can't fix!

All the best!
Do
 
I just wish the 90 degrees LM3886 was still available so we wouldn't need to do it manually but there's nothing a little DIY can't fix!

I do too. It would make the Modulus-186, -286, and -686 much more cost-effective to produce. All the mechanical components could be replaced by a single plate. Unfortunately, bending the leads is not really feasible in a production workflow.

Tom
 
Hope it is OK to post this here.

I bought one of these modules to power a part of my speaker system that will no longer be part of my system.

I had intended to eventually get two of them.

In the interim my direction changed.

I have one module that has never been powered.

It is beautifully assembled by Mr. Christiansen - it is the module he sells for $500.00.

If one is considering getting a pair please consider buying one of them from me! I have had it about three months as it has set about on my kitchen table just looking pretty.

I would be happy to get $400.00 for it and would pay the postage to get it to you.

No soldering - NO NOTHING has been done to the module. The wires have not been inserted into the MOLEX connectors. I did split two of them for mocking up purposes - the intention is that one does split these to suit your installation.

Also, have a pair of MODUSHOP heatsinks. They were recommended by Mr. Christiansen. They are the larger of the ones he recommends. I had intended to get another one which is why I have two. If any of this is of interest let me know, please.

I am eliminating a part of my speaker system. I have not found a better amp for the location - the need has been eliminated.
 
But the thermal performance of a heatsink is only weakly dependent on the colour. They work mainly by convection. [...] Anodizing is cosmetic only - which is why some heatsinks are anodized in funky colours like blue or red (or even gold plated).

Would you happen to have a reference for that handy? I think that would be good information to have on my Taming the LM3886 - Thermal Design page.

Tom