Modulus-86 build thread

I have found that the Modulus-686 sounds better than the Modulus-86, at least on my mid-efficiency LXmini speakers. I can't quite tell if the Modulus-686 sounds better than the Modulus-286 Rev. 2.0 in that application. I suspect it's my imagination, but it might not be.

Tom,

The Modulus-86 and Parallel-86 amps were SOTA ultra low distortion amps with vanishingly low THD - AFAIK at levels far below the threshold of human hearing?

Should your newer amps with even lower THD sound better to human ears because of THD only, or do you suspect/know that something else is going on? For many listeners, certain colorations to the sound can sound better, but what we know of your approach, you design to eliminate noise and distortion altogether.

At the end of the day is it simply a matter of more watts of the Modulus-686 driving your mid-efficiency speakers better? Again, a WAG only, and it might not be that simple. ;)

Again, kudos for your efforts to continuously improve your products and push the envelop. :) And the work you've put in to make integration easier by providing the option for mounting brackets - that also deserves a mention.
 
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Tom, if you need another set of ears to conduct a long term listening comparison of the 686 and new 286 in a couple of different systems, I think you still have my shipping address on file.:D
According to Canada Post, the kit should arrive tomorrow, which’ll give me an excuse to clean off at least a small corner of my work bench.
 
The Modulus-86 and Parallel-86 amps were SOTA ultra low distortion amps with vanishingly low THD - AFAIK at levels far below the threshold of human hearing?

The THD, IMD, etc. are certainly below audible. I suspect the changes I experience between the MOD86 and 286, 686 are due to the higher power and maybe the lower noise floor, all of which are measurable.

Again, kudos for your efforts to continuously improve your products and push the envelop. :) And the work you've put in to make integration easier by providing the option for mounting brackets - that also deserves a mention.

Thank you.

Tom, if you need another set of ears to conduct a long term listening comparison of the 686 and new 286 in a couple of different systems, I think you still have my shipping address on file.:D

... or if I need an excuse for a road trip. :) I'm thinking to take some time off after I graduate. Spending two weeks camping would be rather epic. I need to de-stress somehow, I just haven't settled on the specifics yet. I do need to be a little careful with my time as I'm also taking off for about two weeks in June for a trip to Europe. My mom and I will be scattering my dad's ashes, so I'm thinking it won't be a super relaxing trip, though we are planning to make the best of it and have a vacation nonetheless.

According to Canada Post, the kit should arrive tomorrow, which’ll give me an excuse to clean off at least a small corner of my work bench.

I suppose I should wrap up the assembly guide then. :)

The remaining 25 chassis have arrived in Calgary. FedEx has them and I'll have them by this time tomorrow. Ahhh... A project is approaching the finish line. I like it.

Tom
 
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This is what 25 ModuShop chassis look like. I had FedEx hold the delivery so I could pick it up. I wasn't able to guarantee that I could be around for their delivery until Friday and I want to ship the chassis then. The two pallets just fit in my car with the backseat down.

I love the packing job. The large boxes were stretch wrapped to the pallets. The boxes had cushioning inside, which I removed for the photo. Then each chassis in its individual box. Awesome. I haven't cracked one of the small boxes open yet, but I suspect another layer of foam and/or bubble wrap. These guys are pros at this.

Aluminum... So much aluminum. 83 kg in all (though that probably includes the weight of the pallets). :)

Tom
 

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Another Modulus-86 is Born!

I've long had the Mod86 on my "want to build" list. But I also used to have more amps than any sane person needs, so I couldn't justify having yet another amp. Note the emphasis on used to have... I boxed up four of my amps to have them measured by Amir at AudioScienceReview, and FedEx lost them. Completely lost, now I'm working on the claim process. We'll see how that goes.

The FedEx situation turned out about as good as I could hope for, all things considered. They refunded me the full declared value for each of the two boxes, plus refunded the shipping fee. When I initially specified the declared value, I put in $500 per box, but their website came back and said that amount requires additional insurance to be purchased. So I dropped it down to $400/box. Well, after spending hours pulling all the invoices for all the parts used, I had well over $1100 worth of parts in those two boxes. Of course, I never expected the boxes to be completely lost, so didn't think extra insurance was necessary. Plus, until I was forced to do the exercise of tracking down all the invoices, I didn't really have a good idea what it was all worth any way. Oh well.

On a better note: I just finished my Modulus-86 Build. I had it almost completed last weekend, but somehow screwed up my Mouser order, and decreased the quantity of one resistor value from four to one. So only today did I receive the missing parts and finish assembly.

I've been using the "little brother" of the Mod86 for a while, see my LM3886DR build.

My Mod86 boards are built exactly to Tom's BOM and guidelines. The power supply is the RingNot, because I already had some of those boards on hand. Transformer is the Antek AS-2222. Case is from the diyAudio Store (Modushop), Mini Dissipante 2U 300x330. I had them do custom machining on the back panel. I created the design in Front Panel Designer, then exported to DXF. In the attachment list to this post is a zip file containing the FPD and DXF files for the rear panel cutouts, in case anyone else wants to use it.

Initial impressions are great! I don't think my ears are anything special, but I certainly don't hear anything objectionable. Has really "black blacks", which I like, and an overall incredibly "clean" sound. That's all I've got right now for verbal feedback; need more time with it to make any further commentary.
 

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Finally

The PCB's (incl. coils) I ordered from Tom's Neurochrome website where delivered really fast. The Mouser part took 7 weeks for delivery (1).

The build was easy. Everything fitted like a glove (2).

After some really big builds in the past, I decided a few years ago to challenge myself to use only the HIFI2000 Galaxy 40mm enclosures. So my plan was a little bit like the third picture.

In the 7 weeks, I had to wait for the Mouser parts I got the idea the 24V power supply wasn't enough. So I draw a new PCB power supply (inspired by Tom's SMPS-86) and ended with the fourth picture.

Now the Modulus '86 delivers really nice clean Watts to my tweeters (Beyma TPL-150).
After some changes to the DSP they sing and shine like never before. :D

Thanks!
 

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Mod 86 build

Hi - probably a stupid question, but Ive just received a mod 86 board in the mail (thanks Tom for the quick delivery). Great looking board and looking forward to the build. I cant for the life of me figure out where to find the component list however. I know there is a BOM in the documentation (mouser project) however how do I determine which resistor corresponds to R1, R2, etc?

Again probably staring me right in the face but cant seem to find it at the moment!
 
Thankyou zgtc, realised i had to get the bom as an excel file - working now!

Um, what?! I'm not sure where you got the Excel file from. If it's from Mouser, the component designators/references are probably wrong.

I updated the Design Documentation recently. It looks like the BOM dropped out. I'll fix it right now. Gimme five minutes then download the Design Documentation again. You should see the BOM on the last page of the PDF. Sorry about that.

Tom
 
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