Oh Mighty ZM...
After much adversity...mainly in the form of household renovations...I have finally found time to build some new amp cases.
Unfortunately, it seems they are most similar in capacity to a 4U/300 Deluxe style case.
You have recommended previously that if I wanted to use something like this as a case for the SissySIT, that it would be sufficient only as monoblocks.
I would like to build a strereo dual mono amplifier in each case.
I built them from some Par(Pi) Metal cases and some heatsinks I bought a few years ago from HeatsinkUSA.
The heatsinks specs are:
Quality extruded aluminum
Alloy: 6063-T6
Width is 12.000"
Fin Height is 1"
Base Height is .300"
Weight is approximately .60 lbs per inch
C/W/3": approximately .85
Each heatsink is 7”X12”. The aluminum case measures 17”X12”X7”.
My dream is to finally build some of your amp designs that I have hoarded over the past few years (SissySIT, J2, LuDef)...and once I figure out which I like best (if that’s possible) build a second so I can pursue some of my active multi-way fantasies.
I’ve been rereading a lot of the related threads...but my brain is just confused and mush now.
I don’t know what the heat dissipation requirements are for these different designs or whether any of them would work in these cases as a stereo dual mono design.
I am a lowly Lego amp builder and have only managed to build the ACA monoblocks, F2J monoblocks and the recent first version VFET from the lottery.
All of them are simpler and had very good resources to help frustrated artist dummies like me.
I had to add cooling fans to my F2J monoblocks because I am a sissy and was worried my case design didn’t ventilate well enough.
I would like to avoid having fans in these amp cases.
Is it possible with the LuDef or maybe the J2?
After much adversity...mainly in the form of household renovations...I have finally found time to build some new amp cases.
Unfortunately, it seems they are most similar in capacity to a 4U/300 Deluxe style case.
You have recommended previously that if I wanted to use something like this as a case for the SissySIT, that it would be sufficient only as monoblocks.
I would like to build a strereo dual mono amplifier in each case.
I built them from some Par(Pi) Metal cases and some heatsinks I bought a few years ago from HeatsinkUSA.
The heatsinks specs are:
Quality extruded aluminum
Alloy: 6063-T6
Width is 12.000"
Fin Height is 1"
Base Height is .300"
Weight is approximately .60 lbs per inch
C/W/3": approximately .85
Each heatsink is 7”X12”. The aluminum case measures 17”X12”X7”.
My dream is to finally build some of your amp designs that I have hoarded over the past few years (SissySIT, J2, LuDef)...and once I figure out which I like best (if that’s possible) build a second so I can pursue some of my active multi-way fantasies.
I’ve been rereading a lot of the related threads...but my brain is just confused and mush now.
I don’t know what the heat dissipation requirements are for these different designs or whether any of them would work in these cases as a stereo dual mono design.
I am a lowly Lego amp builder and have only managed to build the ACA monoblocks, F2J monoblocks and the recent first version VFET from the lottery.
All of them are simpler and had very good resources to help frustrated artist dummies like me.
I had to add cooling fans to my F2J monoblocks because I am a sissy and was worried my case design didn’t ventilate well enough.
I would like to avoid having fans in these amp cases.
Is it possible with the LuDef or maybe the J2?
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chromenuts, I would never say this to a woman, but you have a lovely chassis 
I like the nod to the PassLabs design without being a blatent ripoff 
I like the nod to the PassLabs design without being a blatent ripoff
all of these using regular FW PSU , which means rails nominally 24Vdc, in reality 22V5dc-ish
all of these amps made with Iq in range of 1A5 to 1A8, considering that you always have at least one IRFP in OS, enduring half of channel dissipation
so , 22V5 * 2 * 1A5 (to 1A8) , means 67W5 to 81W of heat per channel
so, if you're having 4U/400 equivalent case, you're good for 1A8
considering that you're in Sissy range of 4U/300, you're good for 1A5 or smidge above, resulting in 55C at top of sinks
all of these amps made with Iq in range of 1A5 to 1A8, considering that you always have at least one IRFP in OS, enduring half of channel dissipation
so , 22V5 * 2 * 1A5 (to 1A8) , means 67W5 to 81W of heat per channel
so, if you're having 4U/400 equivalent case, you're good for 1A8
considering that you're in Sissy range of 4U/300, you're good for 1A5 or smidge above, resulting in 55C at top of sinks
Thank you ZM for that explanation.
My only concern is that I do not want to limit the performance of these amps by restricting them to a lower Iq range that might not allow them to “sing”.
However, I think I can proceed under the assumption that if it appears I’ve reached a limit to their dissipation abilities I can make some babysitters for them with voltage regulators to adjust them for a balance of cooling vs noise.
I’m trying to figure out how far I want to go with the dual mono power supplies.
I realized most of what I have on hand for them are the 15000uf caps I bought to plug into the stores PS boards.
I do have some NOS Nippon Chemicon 33000uf chassis mount caps I could use...they would require hand wiring the supply.
I’ve also been looking at your use of motor run caps in the supply and did some research on the subject.
The Ducati Energia caps aren’t available in the US that I can find. I did find a comment about ASC motor runs by another member who seemed to like them.
I found these:
ASC Capacitors - X386S-60-10-370 - Capacitor, Metallized Polypropylene, 60, 370 VAC, +/-10%, Quick Disconnect - Allied Electronics & Automation
Not sure if they would be a good choice or not.
@Itsmee nicoch58 flocchini...thanks for the compliments.
The design and fabrication process is the one thing I feel I can contribute to on these projects.
It satisfies my desire to be creative...even if I was lazy this time using the Par(Pi) Metal case as a basis.
I’ve gotten a bit tired of starting from scratch with raw materials from the scrap yard lately.
I attached another pic of how I want them to look when they finally have guts and play beautiful music 🤞🤞🤞
My only concern is that I do not want to limit the performance of these amps by restricting them to a lower Iq range that might not allow them to “sing”.
However, I think I can proceed under the assumption that if it appears I’ve reached a limit to their dissipation abilities I can make some babysitters for them with voltage regulators to adjust them for a balance of cooling vs noise.
I’m trying to figure out how far I want to go with the dual mono power supplies.
I realized most of what I have on hand for them are the 15000uf caps I bought to plug into the stores PS boards.
I do have some NOS Nippon Chemicon 33000uf chassis mount caps I could use...they would require hand wiring the supply.
I’ve also been looking at your use of motor run caps in the supply and did some research on the subject.
The Ducati Energia caps aren’t available in the US that I can find. I did find a comment about ASC motor runs by another member who seemed to like them.
I found these:
ASC Capacitors - X386S-60-10-370 - Capacitor, Metallized Polypropylene, 60, 370 VAC, +/-10%, Quick Disconnect - Allied Electronics & Automation
Not sure if they would be a good choice or not.
@Itsmee nicoch58 flocchini...thanks for the compliments.
The design and fabrication process is the one thing I feel I can contribute to on these projects.
It satisfies my desire to be creative...even if I was lazy this time using the Par(Pi) Metal case as a basis.
I’ve gotten a bit tired of starting from scratch with raw materials from the scrap yard lately.
I attached another pic of how I want them to look when they finally have guts and play beautiful music 🤞🤞🤞
Attachments
with proper speakers, there will not be dramatic difference between 1A5 and 1A8 of Iq
same applies for caps - 15mF vs. 33mF (I'm using regularly), if you resort to dual mono PSU
Babysitter - I'm using it in Summer with all amps, caps are much cooler, if nothing else
motor runs - any decent brand is OK
same applies for caps - 15mF vs. 33mF (I'm using regularly), if you resort to dual mono PSU
Babysitter - I'm using it in Summer with all amps, caps are much cooler, if nothing else
motor runs - any decent brand is OK
Hi chromenuts,
I did use these KEMET motor run capacitors, bought from Mouser:
https://www.mouser.com/ProductDetai...VdT/R8zBflubKGyO%2B00Wtmz7YqYOnRn0852CRnxQ9ST
I did use them in my dual mono PSU for my SissySIT; worked well.
Regards, Claas
I did use these KEMET motor run capacitors, bought from Mouser:
https://www.mouser.com/ProductDetai...VdT/R8zBflubKGyO%2B00Wtmz7YqYOnRn0852CRnxQ9ST
I did use them in my dual mono PSU for my SissySIT; worked well.
Regards, Claas
Thank you again ZM.
I am currently using an OB with Lii Audio Crystal 10 and Acoustic Elegance Dipole 15.
I own other 8” fullrange drivers I have switched in and out...Fostex, Tang Band, Lowther.
I use Papa’s B5 with them and play with my different amps.
The AE woofer is currently driven by Hypex amps.
My hope is to make a new bigger baffle and install my pair of Tannoy 3833gg with the AE woofers to help.
That is why I would like stereo amps...to drive high and low sections of the Tannoy.
I think these would all be consider pretty “normal” speakers as far as the load presented to the amplifiers.
This will also require building my Bi-Amp 6-24 kits.
Since this is my first Zen Mod Labs adventure...I would like to do my best to not “Ook” anything up.
Is there one amp of the three (Sissy, J2, LuDef) that you feel I have a better chance of not letting the smoke out of?
I am currently using an OB with Lii Audio Crystal 10 and Acoustic Elegance Dipole 15.
I own other 8” fullrange drivers I have switched in and out...Fostex, Tang Band, Lowther.
I use Papa’s B5 with them and play with my different amps.
The AE woofer is currently driven by Hypex amps.
My hope is to make a new bigger baffle and install my pair of Tannoy 3833gg with the AE woofers to help.
That is why I would like stereo amps...to drive high and low sections of the Tannoy.
I think these would all be consider pretty “normal” speakers as far as the load presented to the amplifiers.
This will also require building my Bi-Amp 6-24 kits.
Since this is my first Zen Mod Labs adventure...I would like to do my best to not “Ook” anything up.
Is there one amp of the three (Sissy, J2, LuDef) that you feel I have a better chance of not letting the smoke out of?
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just take your time and - if in doubt about anything , just ask in appropriate thread
Sissy is most likely least complicated of them, but - as I said - my amps are really simple, even if number of parts is always 10-fold of originating Papamp
though, my amps aren't 10 times better than originating Papamps ....... maybe just few times
if you're willing for some nice spk adventuire, I can give ya MLTL plans for 3833
then it'll run in circles around any factory Tann box
and yes - best xover for these is plain CPA15 type (attached) - no frills no gimmicks
example/parallel - I have System 1200 boxes - got them through gifts exchange with good Buddy of mine - boy - so called Monitor series , and xover is bloody nightmare sounding ; and fact is that they ( Tann) already had much better sounding xover for 12" Tulip driver - CPA12 type
Sissy is most likely least complicated of them, but - as I said - my amps are really simple, even if number of parts is always 10-fold of originating Papamp
though, my amps aren't 10 times better than originating Papamps
....... maybe just few times if you're willing for some nice spk adventuire, I can give ya MLTL plans for 3833
then it'll run in circles around any factory Tann box
and yes - best xover for these is plain CPA15 type (attached) - no frills no gimmicks
example/parallel - I have System 1200 boxes - got them through gifts exchange with good Buddy of mine - boy - so called Monitor series , and xover is bloody nightmare sounding ; and fact is that they ( Tann) already had much better sounding xover for 12" Tulip driver - CPA12 type
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Hi Claas
Thank you for your response and that information.
I saw much of your SissySIT build while I was re-reading the related threads...but couldn’t make out which motor run caps you used.
This is helpful.
Thank you for your response and that information.
I saw much of your SissySIT build while I was re-reading the related threads...but couldn’t make out which motor run caps you used.
This is helpful.
just take care that many pcb fabs are having final number of holes per normal pcb
vias are included in count
for anything above that, there is additional fee
vias are included in count
for anything above that, there is additional fee
Thanks, ZM. Did not have this problem with AllPCB. Had to pay extra for the V-score between the channels though. Overall it was $27 per 5 pcs. ($5.40 per peace) - cheap enough, I suppose. But FedEx shipping and local customs intermediaries made me broke 🙁 Anyway, every pleasure has its cost 🙂
I've completed a LuDEF!
The pot adjustments for offset and bias all
went as expected with correct values set.
But audio output is extremely low on both channels -
can just barely hear it.
I've checked all the values and part locations.
I'm using an Edcor 600/600.
Is this the right one?
I noticed Sissy and M2 use the Edcor 600/15K.
-Bruce
The pot adjustments for offset and bias all
went as expected with correct values set.
But audio output is extremely low on both channels -
can just barely hear it.
I've checked all the values and part locations.
I'm using an Edcor 600/600.
Is this the right one?
I noticed Sissy and M2 use the Edcor 600/15K.
-Bruce
Thanks...I do have a question about the power supply...I suppose that can go in any thread.
I’m just trying to organize my case layout (mostly just copying you as best I can)...but running out of room fast.
See pic.
I thought of making up for lower capacitance 15000uf caps I have on hand to stuff boards by adding some of the big 33000uf caps at the end of the cap boards...sort of CRCC?...and then taking power from top of biguns?
This would prevent install of any bypass motor runs...no more room.
If I have to chose between more capacitance or the motor run bypass...is more capacitance the winner?
Also...since I would have to order the motor runs anyway...would it be just as good to search for big (50 uf 400V?) film caps and hang them on big electrolytics as bypass caps?
Another question I have...the subject of the small ceramic bypass cap on the graetz bridges was brought up before.
I did not understand your response about its value...”thumb of rule cell from yore - 1K+1nF” in the Sissy thread.
I don’t have any ceramic caps like yours in my drawers ...maybe some mylar, tantalum, silver mica...not in a lot of values.
I would be interested to see the MLTL plans.
My drivers are still mounted in their original System 15 DMT II boxes.
I have listened to them with all the amps I have built and some EL34 push pull amps I have. They all sound nice, but the bottom end comes up short.
These speakers are supposedly designed for higher power (50watts minimum according to Tannoy)...and seem to be known to be thin on bass.
I think it has something to do with how Tannoy designed them to be soffit mounted in studios.
Since they are so big, it doesn’t seem worth it to come up short on bass.
If the MLTL can improve the bass and be a similar size...maybe taller with smaller footprint?...it might be a good option.
I originally thought of mimicking your Tannoy open baffle project with a helper woofer and using the active Bi-Amp project to control things.
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MLTL, just give me a buzz on e-mail
you'll end up with spks having everything and never asking for more oomph than FW format amp is usually giving
filter = more uF, the merrier
bypass - what counts is number of uF, not size; I;m using motor runs because they're cheap, super quality, easy to mount and only drawback is size and i like sense of cheating Audiophoolery whenever I can
just imagine Papa's green, while selling as hotcakes amps with zillion caps in signal chain, to usually UberKosherOnlyPartsFromHeaven target group ........... because suddenly some of them actually engaged ears
lazy to search around, so find enclosed pics of minimal sized MLTL recently made for her living room (size sorta being matter - everything is hers - kid, house, pets, me, car ...... all I have is workshop and few motorbikes )
you'll end up with spks having everything and never asking for more oomph than FW format amp is usually giving
filter = more uF, the merrier
bypass - what counts is number of uF, not size; I;m using motor runs because they're cheap, super quality, easy to mount and only drawback is size and i like sense of cheating Audiophoolery whenever I can
just imagine Papa's green, while selling as hotcakes amps with zillion caps in signal chain, to usually UberKosherOnlyPartsFromHeaven target group ........... because suddenly some of them actually engaged ears
lazy to search around, so find enclosed pics of minimal sized MLTL recently made for her living room (size sorta being matter - everything is hers - kid, house, pets, me, car ...... all I have is workshop and few motorbikes
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Thank you ZM for all your guidance.
Those MLTL look very nice.
They seem like an ideal solution.
The boss allows me to play with my toys pretty freely. I don’t really have any other bad habits.
However, I’m sure she would appreciate something so nicely proportioned in the living room...especially if it sounds so nice. 😉
Those MLTL look very nice.
They seem like an ideal solution.
The boss allows me to play with my toys pretty freely. I don’t really have any other bad habits.
However, I’m sure she would appreciate something so nicely proportioned in the living room...especially if it sounds so nice. 😉