Modulus-86 build thread

No need for any additional components on the differential lines. Just build the Modulus-86 according to the BOM and plug its input into the differential output of your DAC.



Mostly by routing magic smoke between devices. It's that smoke that you let out when the part fries. Gotta keep it inside the part. This is important! :)

On a serious note: There's good description of how the THAT1200 works in its data sheet: THAT Corporation 1200-series InGenius High-CMRR Balanced Line Receiver ICs

Tom

Ok tks!
I measure 2.9 dc volt between + and ground and - and ground.
Do i need to connect ground???
With transformers i only connect the + and - , not the ground.
 
Directly from the design documentation. Notice the filled solder dots on the ground connections to the chassis. That means you have a connection there. This is also described in the text.

Tom
 

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Directly from the design documentation. Notice the filled solder dots on the ground connections to the chassis. That means you have a connection there. This is also described in the text.

Tom

Ok i understand that but i don t have chassis. I have all the boards on a wood base.
In that case what is the best way to do?
Right now i connected the ground from analog dac ps to modulus 86 xlr ground by wire....
 
Ok i understand that but i don t have chassis. I have all the boards on a wood base.
In that case what is the best way to do?
Right now i connected the ground from analog dac ps to modulus 86 xlr ground by wire....

In that case the DAC supply ground should go to the MOD86 supply ground. DAC signal ground should go to pin 1 of the MOD86 input. Signal+ should go to MOD86 input pin 2 and Signal- to pin 3. If the DAC does not have differential out, take the DAC signal ground to MOD86 input pin 3.

Tom
 
Need to have the wider amp chassis to fit in 6 channels. I ordered the analog crossovers from the DIYAudio store (someday it should show up) which are only the 2 channels. I will try that out first. Running balanced so I picked up two boards. Long term idea was to put the crossover in a similar size chassis under the amp. When I add subs I will most likely use dsp and a classD amp that I have. The studio driver is a bit pricey, so I will most likely try something less expensive. So 2 channels per lx-mini speaker seems OK, but we will see how things play out. First thing is to get the lx-mini drivers and build it.
 
photos of my Modulus 86 build

I had forgotten to show my build, ran across the pictures today, so here it is.

I am still very very happy with the amp. Certainly the cleanest, crispest sound i have had in audio amps.

2U X 300 Dissipante chassis.

My old ears are very sensitive to system distortion, so these low distortion amps have made my listening more enjoyable.

Power supply is the SMPS-86 with Meanwell 24v bricks.

Standard build of the Mod 86 boards, my own hand-wound inductors, obviously.

It has functioned flawlessly with 95db sensitive 8 ohm speakers, providing all the power ever needed.

Thanks, Tom!
 

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Those who'd like a bit more of a turnkey build experience should consider my newly launched Modulus-186 and Modulus-286 Rev. 2.0. You can find them in the solid state section of my web store: Solid State Power Amplifiers & Power Supplies | Neurochrome :: Audio

The intro sale will close by November 30th. I expect to have the modules in stock by then.

The Modulus-186 is basically a Modulus-86 in SMD, professionally assembled. I've started a separate vendor's thread for it: Neurochrome Modulus-186: 40W (8Ω); 65W (4Ω) @ <-120dB THD Composite Amplifier Module

I'll keep the Modulus-86 going for as long as I can get the parts for it. In fact I just opened another pack of 100 boards, so it'll be around for a some time to come. :)

Tom
 
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How this started...
Somewhere a year and a half ago I treated myself to a rather expensive amplifier. That expensive amplifier had a rather anoying mains hum, and because of that, I was not a happy customer. No more amplifiers with transformers I decided and stumbled over the hypex NC400. Great! No mains hum, incredible wide soundstage, detailed bass. Some say it is harsh, but I felt it was no more harsh than that expensive amplifier... .


Then I decided to built the modulus-86. mainly to check out whether I like the sound signature.



I'm using one connex +/- 30V smps300RE power supply per module. Probably more than needed.

Without asking anything, the first thing my wife said when taking out the NC400's and putting the modulus 86 in place was 'sweet'. 'sounds much better'. Which is quite a difference from the 'maybe, sounds all the same to me...' I get typically.


Another interesting side effect is that I suddenly have DAB radio reception again. Not sure whether or where the ncores or the hypex smps taking that out. Makes you wonder about other things... .


So far, I planned to do some A/B testing, but couldn't bring myself taking the mod-86-es out. At domestic sound levels... A really great amplifier.



Thanks Tom
 
[...] hypex NC400. Great! No mains hum, incredible wide soundstage, detailed bass. Some say it is harsh, but I felt it was no more harsh than that expensive amplifier... .

That was my experience with the NC400 as well. Solid bass. Good imaging. Harsh highs - but no more than you'd expect from most other amps.

I'm using one connex +/- 30V smps300RE power supply per module. Probably more than needed.

Good choice.

Without asking anything, the first thing my wife said when taking out the NC400's and putting the modulus 86 in place was 'sweet'. 'sounds much better'. Which is quite a difference from the 'maybe, sounds all the same to me...' I get typically.

I went the other way. I'd been using my Modulus-86 for about a year when a forum member shipped me an NC400 so I could measure it. Naturally, I had to plug it into the stereo. While I enjoyed the tight grip on the bass, I didn't like the highs. I missed the MOD86.

Another interesting side effect is that I suddenly have DAB radio reception again. Not sure whether or where the ncores or the hypex smps taking that out. Makes you wonder about other things... .

Oh, that's interesting. It'd be interesting to plug the NC400 in. Just plug it into the mains and turn it on. See if the reception goes down. If not, connect an input cable (leave the other end floating) and see if the added antenna changes anything.

So far, I planned to do some A/B testing, but couldn't bring myself taking the mod-86-es out. At domestic sound levels... A really great amplifier.

That's awesome. Thanks for writing. I appreciate it. Those who wish for sound levels exceeding 'domestic' now have the Modulus-686 as an option. :)

Tom
 
Oh, that's interesting. It'd be interesting to plug the NC400 in. Just plug it into the mains and turn it on. See if the reception goes down. If not, connect an input cable (leave the other end floating) and see if the added antenna changes anything.


Tom




I tried the "just plug in the mains" this morning (with the NC400 on top of the mod-86 on top of the tuner...). No change at all (i.e. still good DAB reception). I'll plug in some connectors soon.



Rob