chrisb:
I knew what you meant. Any earlier poster asked if inverting the board would have any effect on cooling. My answer to that would be "minimal, (if even measurable). Conduction cooling of the LM3886's is the dominate mechanism of heat transfer for the design, and the majority of power dissipation comes from those parts.
Steve
I knew what you meant. Any earlier poster asked if inverting the board would have any effect on cooling. My answer to that would be "minimal, (if even measurable). Conduction cooling of the LM3886's is the dominate mechanism of heat transfer for the design, and the majority of power dissipation comes from those parts.
Steve
Need binding posts?
You can find them here: https://www.neurochrome.com/product/binding-posts-2/
Tom
You can find them here: https://www.neurochrome.com/product/binding-posts-2/
Tom
Attachments
Comparison Mod286 Monoblocks with Mod686 Monoblocks
Hi.
As promised a while back, I wanted to share my impressions when comparing my two Mod686 monoblocks (20dB gain) as described here
https://www.diyaudio.com/forums/ven...wer-amp-extremely-low-thd-85.html#post5581125
with my two Mod266 monoblocks (20dB gain) as illustrated in this thread
https://www.diyaudio.com/forums/chip-amps/309848-mod-286-build-thread-14.html
The objective was to find any difference in tonality between the two pairs.
The tests were conducted at a constant setting providing a max 0.5W output level (was the right level of loudness for me to catch the details and not have the room vibrate). Of course the tests represent only my subjective impressions. I choose three music titles, one for comparing the highs, one for the bass and one for soundstaging. I listened three times to the first 30 to 60s of each song, before switching amps, which took about 30s total. The speaker were the KEF R700 (8ohms, 3.2ohms min) at a distance of 2.5m with the Auralic Altair as a source and pre-amp. Just to be sure I compared the output levels from the Amps and even adjusted for the 37mVACrms difference between the Mod286s (2.035VACrms) and the Mod686s (1.998VACrms) tested without load using a 1kHz, 0dBs, 24bit, 96kHz testtone coming from the Altair.
Summary: It was not easy as the brain plays tricks on you, but I think, I could not hear a difference between the two amps into these speakers at those power levels. The power levels were not very high for the weaker Mod286 to run out of breath nor is the impedance behavior of the speakers very demanding. After all the amps measure pretty much identical with only minute differences.
Hi.
As promised a while back, I wanted to share my impressions when comparing my two Mod686 monoblocks (20dB gain) as described here
https://www.diyaudio.com/forums/ven...wer-amp-extremely-low-thd-85.html#post5581125
with my two Mod266 monoblocks (20dB gain) as illustrated in this thread
https://www.diyaudio.com/forums/chip-amps/309848-mod-286-build-thread-14.html
The objective was to find any difference in tonality between the two pairs.
The tests were conducted at a constant setting providing a max 0.5W output level (was the right level of loudness for me to catch the details and not have the room vibrate). Of course the tests represent only my subjective impressions. I choose three music titles, one for comparing the highs, one for the bass and one for soundstaging. I listened three times to the first 30 to 60s of each song, before switching amps, which took about 30s total. The speaker were the KEF R700 (8ohms, 3.2ohms min) at a distance of 2.5m with the Auralic Altair as a source and pre-amp. Just to be sure I compared the output levels from the Amps and even adjusted for the 37mVACrms difference between the Mod286s (2.035VACrms) and the Mod686s (1.998VACrms) tested without load using a 1kHz, 0dBs, 24bit, 96kHz testtone coming from the Altair.
Summary: It was not easy as the brain plays tricks on you, but I think, I could not hear a difference between the two amps into these speakers at those power levels. The power levels were not very high for the weaker Mod286 to run out of breath nor is the impedance behavior of the speakers very demanding. After all the amps measure pretty much identical with only minute differences.
Attachments
Tickled pink that folks are enjoying Tom’s 686.
HarmonicTHD, thanks for the comparison and the fastidious setup procedures to minimize listening bias. Your results are what would be expected. My speakers are 96 dB efficient and I would probably not hear differences even at deafening SPL levels. What was your average SPL in your experiment?
The KEF R700’s are properly engineered speakers. I’m sure you’ll enjoy the Reference 5’s some day.
Best,
Anand.
HarmonicTHD, thanks for the comparison and the fastidious setup procedures to minimize listening bias. Your results are what would be expected. My speakers are 96 dB efficient and I would probably not hear differences even at deafening SPL levels. What was your average SPL in your experiment?
The KEF R700’s are properly engineered speakers. I’m sure you’ll enjoy the Reference 5’s some day.
Best,
Anand.
I really dislike RCA connectors.
Part of the reason for building DIY stuff is you can get your gear just like you want it. Only RCA connections that I am putting in is the phono input, since I have RCAs on it.
Easily removed with wire cutters
I made a phono lead using Van Damme starquad, using the tonearm earth and splitting it into 2 Neutric XLR plugs.
Though my phono stage is not fully balanced the shield is carried from the case >pre>Mod 86Parallel.
Hello everyone!
I've decided to do a non-standard build of the Modulus-686 that will be powering my Sagwee LT V3 speakers. For this, I've decided to install the LM-3886 chips in a 90 degrees bend to provide more room in my chassis. I've also decided to use 0.5mm alumina/ceramic pads for the LM-3886 as they provide amazing heat dissipation.
Here's some pics of the modules.
All the best & Happy New Year!!
Do
I've decided to do a non-standard build of the Modulus-686 that will be powering my Sagwee LT V3 speakers. For this, I've decided to install the LM-3886 chips in a 90 degrees bend to provide more room in my chassis. I've also decided to use 0.5mm alumina/ceramic pads for the LM-3886 as they provide amazing heat dissipation.
Here's some pics of the modules.
All the best & Happy New Year!!
Do
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Do,
I’m tickled pink that you are building Tom’s SMD designs, you are a pro builder! I think you will enjoy the amp, they are indeed a reference standard imho!
Chris, I think Do is building it the way he is to allow for more room in the chassis, not because of the loudspeaker design itself.
I am actually curious to see how they sound with your Troels ATS design in addition to the Sagwee.
Best,
Anand.
P.S. My 286 v2.0 just arrived in the mail!
I’m tickled pink that you are building Tom’s SMD designs, you are a pro builder! I think you will enjoy the amp, they are indeed a reference standard imho!
Chris, I think Do is building it the way he is to allow for more room in the chassis, not because of the loudspeaker design itself.
I am actually curious to see how they sound with your Troels ATS design in addition to the Sagwee.
Best,
Anand.
P.S. My 286 v2.0 just arrived in the mail!
I do like this idea a lot, you really going to save a lot of space in the case .
Where did you order the ceramic pads from?
Thanks
Happy new year!