New Leco Amp modules 650W/8R-1200W/4R
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Category: General
Forum Name: Amp Forum
Forum Description: The 'Stopping Jake Fielder moaning constantly' forum description...
URL: https://forum.speakerplans.com/forum_posts.asp?TID=84281
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Topic: New Leco Amp modules 650W/8R-1200W/4R
Posted By: DjLeco
Subject: New Leco Amp modules 650W/8R-1200W/4R
Date Posted: 01 January 2014 at 2:28am
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Some improvements compared to the previous version: 6 output devices per rail. Triple deep darlington configuration, full simmetrical from in to out. Offset adjustment. Faster transistors on differential and VAS stages, with lower Cob capacitance. Double feedback pre-post L-R out filter. Improved output shortcircuit protection with faster transistors and lower Vce saturation. Improved randament regarding passing from AB class to B class above 60 celsius degrees, with dinamic bias. Some specifications: Supply from +/- 70 to +/- 115Vdc, output power 650 watts 8 ohms and 1200 watts 4 ohm at +/- 115Vdc. Damping factor >1000/8ohms/100Hz. Rise rime/fall time 2,5uSec, tipically 2,18uSec measured at 10Khz/8 ohms. Freq response 15Hz-20Khz -1db at extremes, 5Hz-30Khz -3 db at extremes internally limited. Some pictures: http://postimg.org/image/9rpevluof/" rel="nofollow"> http://postimg.org/image/p1pa2sq6n/" rel="nofollow"> Some movies and tests: Presentation: https://www.youtube.com/watch?v=STP1g9luils" rel="nofollow - https://www.youtube.com/watch?v=STP1g9luils Classical bias class AB: https://www.youtube.com/watch?v=eyx1gNlNC0Y" rel="nofollow - https://www.youtube.com/watch?v=eyx1gNlNC0Y dinamyc bias passing from AB class to B class when temperature rises: https://www.youtube.com/watch?v=CysVsbNnvGM" rel="nofollow - https://www.youtube.com/watch?v=CysVsbNnvGM Rise and fall times: https://www.youtube.com/watch?v=40tmueYkMqo" rel="nofollow - https://www.youtube.com/watch?v=40tmueYkMqo Max out 8 ohm: https://www.youtube.com/watch?v=tJkwmLvt5UI" rel="nofollow - https://www.youtube.com/watch?v=tJkwmLvt5UI Max out 4 ohm: https://www.youtube.com/watch?v=Lcl-gFMOFkw" rel="nofollow - https://www.youtube.com/watch?v=Lcl-gFMOFkw Maximum RMS current preset for 4 ohms during 2 ohms load: https://www.youtube.com/watch?v=KfW4R9Pr5v0" rel="nofollow - https://www.youtube.com/watch?v=KfW4R9Pr5v0
------------- I'm A Stupid SMART Romanian... |
Replies:
Posted By: TRE4U2NV
Date Posted: 01 January 2014 at 2:42am
 as usual well done sir ------------- IM SO SECRETIVE BUT I CANT TELL YOU WHY |
Posted By: all bass
Date Posted: 01 January 2014 at 9:16am
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My hat's off to you sir! ------------- https://www.instagram.com/my_modular_journey/ |
Posted By: Nitz V1505
Date Posted: 01 January 2014 at 10:13am
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Truely inspirational!!!! Hats off Sir. Id love me a few of those. ------------- LET THE BASS ROLL LIKE THUNDER & THE TOPS LIKE LIGHTNING..... |
Posted By: DjLeco
Date Posted: 01 January 2014 at 11:30am
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Thank you all for nice words, I want to wish you all, HAPPY NEW YEAR!
Me too, I like the results of new version, especially how protection WORKS.
I have 10 pieces (without heatsink) for sale, but I don't know how to proceed with transport from Romania, to you...
Maybe someone can help for that, with some opinions. ------------- I'm A Stupid SMART Romanian... |
Posted By: Tan-2
Date Posted: 01 January 2014 at 8:08pm
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impressive.... ------------- Logic will get you from A to B. Imagination will take you everywhere. |
Posted By: Earplug
Date Posted: 02 January 2014 at 9:05am
Nice. What sort of price range are we talking (trade, of course)?  ------------- Earplugs Are For Wimps! |
Posted By: ArthurG
Date Posted: 02 January 2014 at 9:13am
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Leco, Seems a nice design. congrats mate What are the output transistors ? |
Posted By: TONY.A.S.S.
Date Posted: 02 January 2014 at 9:13am
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Careful, don't get the man thrown out for selling. ------------- http://www.facebook.com/tony.rossell.3" rel="nofollow - http://www.facebook.com/tony.rossell.3 |
Posted By: Earplug
Date Posted: 02 January 2014 at 1:46pm
Just a friendly question! And a PM would avoid any misunderstanding! ------------- Earplugs Are For Wimps! |
TONY.A.S.S. wrote:Posted By: DjLeco
Date Posted: 02 January 2014 at 4:55pm
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All discussions are friendly, no problem gentlemans!
In the new year we must be more good, more understanding, more maleable.
Output devices are MJW21195+MJW21196, very robust if not exceeding SOA curve.
Modules are just for selling, not exchanges.
 Someone on other forum tryed to throw dirty on my work, saying the amp will not survive playing sinewave in shorted output, at variable signal level, because sensing transistors of protection, cannot act so fast...
I laught and I offered him his video, to chill itself...
Also shared to all of you:
https://www.youtube.com/watch?v=9m1sVXeFgck" rel="nofollow - https://www.youtube.com/watch?v=9m1sVXeFgck
Comments are welcomed! ------------- I'm A Stupid SMART Romanian... |
Posted By: ArthurG
Date Posted: 02 January 2014 at 5:33pm
Those are very good transistors ! But why did you choose 21195+21196 over let's say 21193+21194 that have even higher SOA in a smaller package ?
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Posted By: Marko
Date Posted: 02 January 2014 at 6:17pm
Great video, especially the crazy part at 05:00 min... I would also like to know the price, please PM |
Posted By: DjLeco
Date Posted: 02 January 2014 at 6:57pm
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Price will ve 150 euros without heatsink, just 4 pieces are with heatsink, wich are reserved deja by one customer.
MJW21195,MJW21196, have same SOA as MJL21193,MJL211194 just package is a little smaller for MJW (TO247 vs TO264), that's why I have used MJW, because smaller package same SOA, also I cannot fit 12xTO264 on that heatsink+2x TO3P prefinals, not enough space to fit'em.. ------------- I'm A Stupid SMART Romanian... |
Posted By: ArthurG
Date Posted: 03 January 2014 at 4:11am
oh misunderstanding, I was talking about NJW21193G + NJW21194G, which are TO-3P, slightly smaller than MJL TO-247 (by a very small margin, in real life it doesn't make any difference on pcb/heatsink size). But SOA on NJW21193G is a bit better than the MJL you use. At 100V it takes 4A for 100msec vs 3.5A on MJL. In fact, NJW21193+21994 has the highest SOA of ON Semi bipolar range and it's the pair of choice of Lab.Gruppen class TD amps  |
Posted By: SMP
Date Posted: 03 January 2014 at 7:13am
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please explain why you wish to change class with temp? surely class AB is fine and no real need to change bias coz of heat? I have never found any need to change biasing due to a temp change. incidentally I use 4281/4302 for a class AB I develop here |
Posted By: DjLeco
Date Posted: 03 January 2014 at 9:17am
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I bought some time ago 125 pairs of MJW21195+21196, and I must to use it. Also I have couple tens of pairs of NJW21193-21194, as I will use it.
When heatsink is cold, on AB class will pass just bias curent in idle mode, with classical superdiode.
During high curent passing on output devices the heatsing temperature will grow, superdiode trying to compensate (decrease bias) until official value, but the bipolar transistor have negative coeficient temperature, and will have tendancy to increase current colector same time with temperature, because slow compensation of superdiode circuit, when teatsink is hot (70 degrees above), the bias will be higher in idle mode, and dissipate more heat, existing risk to thermal avalanche, if bias are a little higher than one predefined value.
Thats's why , On Semi, developed THERMAL TRACK trannies, with indide bias diode (5 pins).
Also, I used smaller heatsink for mine application, and B class amplifiers have bigger randament than AB class amplifiers.
So why is that I prefear to slow bias untill B class, when heatsink temperature increases, I raise up a litlle randament, also higher compensation of negative coeficient temperature of bipolar transistors.
Also, LabGruppen, uses B class amplifiers on their design, eben in TD class amplifiers, bipolar part of it is B class, that's why also they uses small heatsinks ------------- I'm A Stupid SMART Romanian... |
Posted By: SMP
Date Posted: 03 January 2014 at 10:34am
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I see you are using "Amplified Diode" to generate bias..I do not use such an arrangement as temperature co-efficiency is an issue. "differential PD" does not give such issues slightly less stable but is only small not so significant and bias can remain class AB always. Yes TD is a class B Topology aids in efficiency but does little to sonic ability always an issue were differential driver circuits are used also in class B. I use pure class A drive run hot but sonics much better than Cascoded drive which require higher component count as they need more CCS's to operate effectively and have too many PN Junctions in signal path which can cause non-linearity at high signal swings and inferior transfer function. But each to their own I guess and we each do our own thing |
Posted By: Tan-2
Date Posted: 03 January 2014 at 6:37pm
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We sure do... But it's also interesting to see different designs.. ------------- Logic will get you from A to B. Imagination will take you everywhere. |
Posted By: M4trix
Date Posted: 03 January 2014 at 11:37pm
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Leco, your dummy load is dying! If the dummy load had ability to speak it would say... please, hook me off cuz I can't stand this torture anymore!  |
Posted By: DjLeco
Date Posted: 04 January 2014 at 12:36am
I will use it until it will be "open circuit".
I don't have place to put mine 1 ohm/1000Watts resistors(4 pieces/channel)...
http://www.digikey.com/product-detail/en/FSE100022E1R00KE/FSE1000-1.0-ND/270007" rel="nofollow - http://www.digikey.com/product-detail/en/FSE100022E1R00KE/FSE1000-1.0-ND/270007
http://www.vishay.com/docs/31849/fse.pdf" rel="nofollow - http://www.vishay.com/docs/31849/fse.pdf ------------- I'm A Stupid SMART Romanian... |
Posted By: DjLeco
Date Posted: 04 January 2014 at 9:06am
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SMP, no more technical discussion.
I said what I have to say, I showed what I have to show.
I don't want to be like other project(first one), where one "colleague" of mine, buyed prototype on test PCB, watched all discussion, tryed then to clone it, and het his self BIG, look mates, there's mine amplifier , and so on...
That colleague nickname is "Black", and he officially STOLE mine schematic and make another type of PCB, saying is HIS project...
http://www.diyaudio.com/forums/solid-state/185594-final-test-module-leco-vs-crown-powertech-series-amplifier.html" rel="nofollow - http://www.diyaudio.com/forums/solid-state/185594-final-test-module-leco-vs-crown-powertech-series-amplifier.html
Post 44 above
http://www.diyaudio.com/forums/solid-state/172617-class-ab-amp-made-me-5.html" rel="nofollow - http://www.diyaudio.com/forums/solid-state/172617-class-ab-amp-made-me-5.html
Here's that PCB that he buyed, stole the schematic and so on:
http://www.diyaudio.com/forums/solid-state/172617-class-ab-amp-made-me.html" rel="nofollow - http://www.diyaudio.com/forums/solid-state/172617-class-ab-amp-made-me.html
Sorry for puttin' links to other forum, but there was that discussion.
------------- I'm A Stupid SMART Romanian... |
Posted By: SMP
Date Posted: 04 January 2014 at 9:15am
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no offence intended I merely ask out of interest. I have no wish or need to "clone" or copy your design I have one or two of my own Class AB both BJT & MOSFET. you clearly believe your design is of commercial value. at present I have no desire to manufacture amplifiers. but when I do I will use my own designs. i merely wondered why there was a need to alter so drastically. as in normal use a class AB will migrate to single phasic conduction as the output voltage swings high. so I could not see any benefit to it. forgive me but I thought this is a forum where ideas and knowledge are freely exchanged guess it is not a forum at all. I could not understand your commentary as not English so I gained no useful exchange from it |
Posted By: SMP
Date Posted: 04 January 2014 at 9:24am
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I am also a DIY member as well "blueroom" http://www.diyaudio.com/forums/solid-state/172617-class-ab-amp-made-me-5.html as the guy said without any topology your test video or results do not mean a great deal it is as you know customary on both DIy & Blueroom to show topology or it becomes pointless a little like showing photos of speakers or the items in physical sense with no sound pointless means nothing as it proves nothing and again circuit is no "Secret" a very simple topology class B is class B it has been done so often |
Posted By: SMP
Date Posted: 04 January 2014 at 9:30am
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and as you were told by other members on DIY forget it no schematic no value or interest academically it is I believe not of any significant commercial value it is "Old Hat" nothing new be happy and be lucky will leave this pointless thread |
Posted By: SMP
Date Posted: 04 January 2014 at 9:32am
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I see your request for "Thread lock" given oh well would have been useful to us both maybe to exchange ideas but i do not think much for me to learn here leaving thread now |
Posted By: MarjanM
Date Posted: 04 January 2014 at 10:54am
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I think most of the members here are interested in what the amp can actually do, and could not care less about the topology. ------------- Marjan Milosevic MM-Acoustics www.mm-acoustics.com https://www.facebook.com/pages/MM-Acoustics/608901282527713 |
Posted By: GEB
Date Posted: 04 January 2014 at 11:12am
+1
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Posted By: DjLeco
Date Posted: 05 January 2014 at 6:32pm
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After finishing those for selling, entire project will be for selling.
Cost will be 350 euros, and next owner will receive enitire documentation and gerber files to produce it.
Just give the files to an PCB manufacturer, and start to make it. ------------- I'm A Stupid SMART Romanian... |
Posted By: Wiljj78
Date Posted: 03 April 2014 at 5:10pm
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Hi leco, What's the price each module? Regards, |
Posted By: DjLeco
Date Posted: 04 April 2014 at 12:19am
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Price for one module is 150 euros, heatsink included. ------------- I'm A Stupid SMART Romanian... |
Posted By: Mark James
Date Posted: 04 April 2014 at 12:35am
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looks good to me [altho im a speaker man not an amp man lol] nice to see someone doing there own thing well done :-] ------------- insert silly sentence here |
Posted By: DjLeco
Date Posted: 04 April 2014 at 1:42pm
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Thank you for appreciations, sir. ------------- I'm A Stupid SMART Romanian... |