My usaula dumb question
You may remember me, i was was always asking simple questions. I not much smarter now so have a question about the 286. Can one be used for right and left channel? That is can one 286 and power 86 be put in an enclosure, with the rest of the stuff, and be used as a two channel stereo amp?
Hi Tom,
You may remember me, i was was always asking simple questions. I not much smarter now so have a question about the 286. Can one be used for right and left channel? That is can one 286 and power 86 be put in an enclosure, with the rest of the stuff, and be used as a two channel stereo amp?
This guy did exactly that: SMPS-86 + MOD286 super compact stereo desktop amp.
With the SMPS-86, do note that you only get about 28 W into 8 Ω and that the supply current limits at 2.5 A, so 4 Ω operation at a reasonable volume is possible, but if you really crank it the supply will current-limit on a 4 Ω load.
Other swichmode options include the SMPS300RE from Connex (get the ±30 V version).
My Power-86 with a mains transformer remains a solid option as well.
Tom
With the SMPS-86, do note that you only get about 28 W into 8 Ω and that the supply current limits at 2.5 A, so 4 Ω operation at a reasonable volume is possible, but if you really crank it the supply will current-limit on a 4 Ω load.
Other swichmode options include the SMPS300RE from Connex (get the ±30 V version).
My Power-86 with a mains transformer remains a solid option as well.
Tom
It's been a while since I've posted on here, but I just wanted to clarify something that could have been misinterpreted.
I did not mean to imply that the MyRef Fremen Edition was "snake oil" in my quoted post, though I now realize that it seems like that's what I was saying.
My "snake oil" comment was more of a reference to the people who doubt the usefulnes of audio performance measurements in general.
My apologies if it was misinterpreted.
two 286s for bi-amping
Seems two 286s in one chassis would be four channels so bi-amping a pair of two way speakers would be doable. Would I need two transformers and two power86s?
Thanks,
Henry
Seems two 286s in one chassis would be four channels so bi-amping a pair of two way speakers would be doable. Would I need two transformers and two power86s?
Thanks,
Henry
Henry,
Here you go with link for a build done by Tom - one SMPS for four channels.
http://www.diyaudio.com/forums/chip-amps/267802-modulus-86-build-thread-284.html#post4927704
Edit: Tom's earlier build with single transformer and Power-86:
http://www.diyaudio.com/forums/chip-amps/267802-modulus-86-build-thread-89.html#post4399918
I am sure Tom will confirm, but it's likely that one Power-86 board with an adequately sized transformer should be enough for your planned build.
Here you go with link for a build done by Tom - one SMPS for four channels.
http://www.diyaudio.com/forums/chip-amps/267802-modulus-86-build-thread-284.html#post4927704
Edit: Tom's earlier build with single transformer and Power-86:
http://www.diyaudio.com/forums/chip-amps/267802-modulus-86-build-thread-89.html#post4399918
I am sure Tom will confirm, but it's likely that one Power-86 board with an adequately sized transformer should be enough for your planned build.
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2 x MOD286 with one Power-86 and an Antek AS3222 would be perfect for a 2-way bi-amp setup. That's essentially what I drive my LXmini speakers with. I use 4 x MOD86 but in terms of power requirements, there's no difference between 4 x MOD86 and 2 x MOD286 (stereo).
If you're going with the Connex SMPS-series, I'd get the ±30 V version of the SMPS500R. The SMPS300RE is a touch underpowered. It works well enough, but if you run all four channels to clipping with a 4 Ω load you exceed the 100 W (RMS) that the SMPS300RE can deliver, even with music signal.
Tom
If you're going with the Connex SMPS-series, I'd get the ±30 V version of the SMPS500R. The SMPS300RE is a touch underpowered. It works well enough, but if you run all four channels to clipping with a 4 Ω load you exceed the 100 W (RMS) that the SMPS300RE can deliver, even with music signal.
Tom
For 4-channel operation you'd need two MOD286 boards running on ±28 V. I'm guessing you run the PAR86 on ±35 V. Also note that you'll need as much heat sinking for one MOD286 board as you do for one PAR86 board, so dropping two MOD286 boards into one enclosure that used to house a PAR86 may not be feasible.
Tom
Tom
Tom,
I currently have ak4490 with passive differential output stage: 2xLL1684 transformers (one per channel). Then it is connected to Modulus-86 with XLR cables. However since DAC and modulus are relatively small I could put them into one box. If in one box, then I could configure LL1684 to sum differential signal and output SE signal. If so, then I think I could somehow skip onboard THAT1200 in modulus 86 board and connect SE signal directly? Can you point where should I connect such SE signal if possible?
Thanks,
I currently have ak4490 with passive differential output stage: 2xLL1684 transformers (one per channel). Then it is connected to Modulus-86 with XLR cables. However since DAC and modulus are relatively small I could put them into one box. If in one box, then I could configure LL1684 to sum differential signal and output SE signal. If so, then I think I could somehow skip onboard THAT1200 in modulus 86 board and connect SE signal directly? Can you point where should I connect such SE signal if possible?
Thanks,
more questions
Thanks,
Henry
I am running the PAR86 on +-35V. The 286 spec.s lists +-35V used for testing. Maybe I'm reading it wrong. Why is 28V needed for one 286 as stereo AMP?
My enclosure houses two PAR86 boards and each has it's own HS, so I thought I would only need to add one more HS for the 286. What am I missing?
Thanks,
Henry
MOD286 - MONO: ±35 V
MOD286 - STEREO: ±28 V
What are you trying to do. I'm lost. I thought you were building a 4-channel amp using two MOD286 boards. No?
Tom
MOD286 - STEREO: ±28 V
What are you trying to do. I'm lost. I thought you were building a 4-channel amp using two MOD286 boards. No?
Tom
Henry,
If we understand correctly, you were thinking if it was possible to use the existing transformer + Power86 which you are using for your Par-86 stereo amplifier to provide power for the new Mod-286 modules that you are planning to install in the same chassis?
If you use each Mod-286 as a mono amplifier (parallel config?) then theoretically your existing Power-86 will be able to power those units (Tom will have to confirm). How big is your transformer?
Hope I am not adding further to the confusion!
If we understand correctly, you were thinking if it was possible to use the existing transformer + Power86 which you are using for your Par-86 stereo amplifier to provide power for the new Mod-286 modules that you are planning to install in the same chassis?
If you use each Mod-286 as a mono amplifier (parallel config?) then theoretically your existing Power-86 will be able to power those units (Tom will have to confirm). How big is your transformer?
Hope I am not adding further to the confusion!
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Yes. If you build four (4) Modulus-286 boards and run them in mono configuration, you'd have a 4-channel amp that will work with your existing power supply, assuming the transformer can provide enough power. You will need two more heat sinks for that to work. In that setup, I recommend heat sinks with a thermal resistance of 0.59 K/W or lower, per channel, and a transformer which can provide at least 89 VA per channel.
This solution will provide 100 W into 4 Ω with a ±35 V supply.
If you want to base the amp on the Modulus-286 in stereo configuration, you will need two (2) MOD286 boards to form a 4-channel amp. In this configuration I recommend a transformer providing at least 99 VA per channel and a heat sink better (lower thermal resistance) than 0.51 K/W per board (= 1.02 K/W per channel). In this configuration I recommend running on ±28 V and you'll get 65 W per channel into 4 Ω.
To summarise:
Board - Configuration - Output power - Supply voltage - Transformer VA - Heat sink thermal resistance.
MOD286 - STEREO - 65 W, 4 Ω - ±28 V - 99 VA/ch - 1.02 K/W per channel (0.51 K/W per board)
MOD286 - MONO (parallel) - 100 W, 4 Ω - ±35 V - 89 VA/ch - 0.59 K/W per channel
If you want multiple channels running on the same heat sink or same power supply, divide the thermal resistances by the number of channels per heat sink and multiply the VA by the number of channels per transformer.
If you want to go from two to four channels, reusing the chassis and heat sink, you'll likely find that you're better off swapping the power transformer.
If, on the other hand, you want four 100 W channels, you'll need to build four MOD286 boards. In that case you'll need to double the amount of heat sink you have and likely double the transformer VA as well. At that point you might as well start over and sell your Parallel-86 amp.
Tom
This solution will provide 100 W into 4 Ω with a ±35 V supply.
If you want to base the amp on the Modulus-286 in stereo configuration, you will need two (2) MOD286 boards to form a 4-channel amp. In this configuration I recommend a transformer providing at least 99 VA per channel and a heat sink better (lower thermal resistance) than 0.51 K/W per board (= 1.02 K/W per channel). In this configuration I recommend running on ±28 V and you'll get 65 W per channel into 4 Ω.
To summarise:
Board - Configuration - Output power - Supply voltage - Transformer VA - Heat sink thermal resistance.
MOD286 - STEREO - 65 W, 4 Ω - ±28 V - 99 VA/ch - 1.02 K/W per channel (0.51 K/W per board)
MOD286 - MONO (parallel) - 100 W, 4 Ω - ±35 V - 89 VA/ch - 0.59 K/W per channel
If you want multiple channels running on the same heat sink or same power supply, divide the thermal resistances by the number of channels per heat sink and multiply the VA by the number of channels per transformer.
If you want to go from two to four channels, reusing the chassis and heat sink, you'll likely find that you're better off swapping the power transformer.
If, on the other hand, you want four 100 W channels, you'll need to build four MOD286 boards. In that case you'll need to double the amount of heat sink you have and likely double the transformer VA as well. At that point you might as well start over and sell your Parallel-86 amp.
Tom
Pluck the THAT1200 from its socket and connect the single-ended output from the LL1684s between pin 6 of the THAT1200 socket and ground (R11).
Tom
Well here's a third Yorkshireman who has recently completed a Paralllel 86 build (in my case in bridged mode) and just like the other two I've been using Ncore 400s for the last few years. The Ncores are great amps and redefined my views on class D. However Misterdog got it right in his comments above. These are superb amps. The Ncores have now been relegated to driving the woofers on my JBL M2s.Having finally got round to building my Parallel 86 and swapping out my Hypex
N-Cores I can say that is a no brainer.
I also use the system for AV use.
Tom's amps are nearly half the price yet provide more of everything (excluding power). Definition, tonal timbre,sound staging. Lyrics are more easily discerned,
instruments have more of an organic shimmer.
What I wasn't expecting was greater bass definition, after all Quad ESL's don't produce bass
Well they do if you provide them with a quality signal and amplification.
I have practically turned off my Subwoofer.
I am so impressed I have just sourced a second set of boards to run them bridged.
Excellent product *****.
Many thanks Tom.