source for capacitors:
go to:
http://www.rs-components.com/index.html
and click on your region on the map. They have big BHC and Sikorel, wich are supposed to be great.
go to:
http://www.rs-components.com/index.html
and click on your region on the map. They have big BHC and Sikorel, wich are supposed to be great.
I will replace the two Rifas in this one with only two BHC to test if this will give the same sound as the other ones (almost dual mono)
Stefan
An externally hosted image should be here but it was not working when we last tested it.
Stefan
Re: comparison of different caps
Is Aerovox the same capacitors as BHC? If so, TNT didn't like them. Any thoughts?
ackcheng said:
Is Aerovox the same capacitors as BHC? If so, TNT didn't like them. Any thoughts?
They specified the "T" network cap too didn't they ?? Maybe they didn't use them right? They might not be a good "drop in" replacement for a regular cap.
I wouldn't take their word on it.
But yeah, BHC = Aerovox = Evox Rifa 🙂
I'd like to know if anyone has tried panasonic computer grades as seen on Digikey?
I wouldn't take their word on it.
But yeah, BHC = Aerovox = Evox Rifa 🙂
I'd like to know if anyone has tried panasonic computer grades as seen on Digikey?
softstart
Hi,
I have a question about softstart. I have some free thermistors, CL60. The resistance of CL60 will decrease when it's temperture goes up. Does anybody can tell me that can the thermistor be used as a softstart? thanks!
Please find the detail information about the said thermistor in the following website.
http://www.myclie.info/images/CL60DATA.pdf
Hi,
I have a question about softstart. I have some free thermistors, CL60. The resistance of CL60 will decrease when it's temperture goes up. Does anybody can tell me that can the thermistor be used as a softstart? thanks!
Please find the detail information about the said thermistor in the following website.
http://www.myclie.info/images/CL60DATA.pdf
Sure,
The problem is, what happens if your amp is warm because you've been listening to it for a few hours, then you cycle the power? (maybe you're tweaking it or something)
You have no in rush limiting because it can't "reset" fast, it might take an hour for your transformer to cool down again.
Not a good option I'm afraid.
The problem is, what happens if your amp is warm because you've been listening to it for a few hours, then you cycle the power? (maybe you're tweaking it or something)
You have no in rush limiting because it can't "reset" fast, it might take an hour for your transformer to cool down again.
Not a good option I'm afraid.
The idea is the thermistor heats up by virtue of the current drawn through it, not being in proximity to a hot component. Your end result is the same though -- these things are only any use for class-a where current draw is much more constant.
So let's say you place it in the coolest part of the amp..
In order for it to have a chance at working even half decent, you'd still have to switch it out of the circuit once its job is done, therefore you'd still have a requirement for a fairly complex soft start circuit with relays and everything. The ambient temp in the amp is no doubt going to rise and have an affect on it anyway, as they are fairly sensative, and it's still going to have an unreasonably long reset time, rendering it basically pointless.
Based on that I dont' think constant current through it is the its achillies heal.
In order for it to have a chance at working even half decent, you'd still have to switch it out of the circuit once its job is done, therefore you'd still have a requirement for a fairly complex soft start circuit with relays and everything. The ambient temp in the amp is no doubt going to rise and have an affect on it anyway, as they are fairly sensative, and it's still going to have an unreasonably long reset time, rendering it basically pointless.
Based on that I dont' think constant current through it is the its achillies heal.
Caps fro Neuhold?
http://www.neuhold-elektronik.at/catshop/product_info.php?cPath=41_51_146&products_id=249
Has anybody tryed theise?
They are cheap javascript:smilie('🙂')
smile
I`ve plan to use 2x4 10.000yF pr. channel in my Zappulse.
Venlig hilsen Jan Jensen🙂
http://www.neuhold-elektronik.at/catshop/product_info.php?cPath=41_51_146&products_id=249
Has anybody tryed theise?
They are cheap javascript:smilie('🙂')
smile
I`ve plan to use 2x4 10.000yF pr. channel in my Zappulse.
Venlig hilsen Jan Jensen🙂
I'm also curious about how well an implementation like this would work and/or what amperage batteries would work. Hearing about what Vinnie R's ClariTamp (a heavily modified Sonic Impact Amp) can achieve with the help of using a sla battery makes me wonder what a ucd180 can do. Considering the Nichicon caps for the ucd180 p/s i'm looking at would cost $22 a piece and I would need four plus a tranny and other misc. stuff, the possibility of using batteries is inviting. Anyone have any comments or direction about this? Thanks
Let's see if I understand this thread correctly.
I'd like to make a 2 channel 400UcD amp, with maximum possible specs. My Nautilus 804 speakers are 8 ohms but are known to dip to 3.3 ohms (newer B&W models even to 3.0)
To insure maximum stability even at the 3.0 extreme, I've made some calculations based on this thread.
I've read somewhere, full power into one module at 8 ohms: 6250uF per rail. That's about 16666uF/rail into 3 ohms, let's make that 15000uF (I'm not going to drive pure 3 ohm speakers anyway) per rail.
So 2 channels at 3.x ohms would require 30000uF/rail - this seems much, did I make a mistake somewhere? I'd love to use Blackgate FK 80V series but these seem to be *very* expensive!
This site mentions adding small caps parallel on the large caps. Is this recommended? Use "bleeders" for keeping the caps happy?
I'd use these with a 1000VA or 1.2kVA with 2*45v secondaries, using 2 rectifiers. (edit: I've read this is is only possible on 2 transformers, so I'll be using one?)
Would this be a very high quality design for this kind of load? Overkill? Not enough? Could it get THX ultra 2 certification? 😉 Nah, just kidding on the last question...
Thanks!
I'd like to make a 2 channel 400UcD amp, with maximum possible specs. My Nautilus 804 speakers are 8 ohms but are known to dip to 3.3 ohms (newer B&W models even to 3.0)
To insure maximum stability even at the 3.0 extreme, I've made some calculations based on this thread.
I've read somewhere, full power into one module at 8 ohms: 6250uF per rail. That's about 16666uF/rail into 3 ohms, let's make that 15000uF (I'm not going to drive pure 3 ohm speakers anyway) per rail.
So 2 channels at 3.x ohms would require 30000uF/rail - this seems much, did I make a mistake somewhere? I'd love to use Blackgate FK 80V series but these seem to be *very* expensive!
This site mentions adding small caps parallel on the large caps. Is this recommended? Use "bleeders" for keeping the caps happy?
I'd use these with a 1000VA or 1.2kVA with 2*45v secondaries, using 2 rectifiers. (edit: I've read this is is only possible on 2 transformers, so I'll be using one?)
Would this be a very high quality design for this kind of load? Overkill? Not enough? Could it get THX ultra 2 certification? 😉 Nah, just kidding on the last question...
Thanks!
Power supply
Hello!
I am Spanish student. I am interested in mounting an amplifier with 2 Ucd 400. I want that it is double monofonica of maximum quality.
That power supply amount?
it´s ok for ucd 180 kit?
Where I can see the schemes?
Can be bought the source already mounted and testeada?
P.D: Sorry about my english...🙁
Thanks and a greeting!
Hello!
I am Spanish student. I am interested in mounting an amplifier with 2 Ucd 400. I want that it is double monofonica of maximum quality.
That power supply amount?
it´s ok for ucd 180 kit?
Where I can see the schemes?
Can be bought the source already mounted and testeada?
P.D: Sorry about my english...🙁
Thanks and a greeting!
Hi, me again.
I think you got the cap size right on, didn't verify the math or anything but your method and reasoning seems sound, and so does the answer.
Good news, it's been said with good authority that black gate PSU caps are junk, they dont' share the same high quality sound their smaller (de)coupling/small signal caps do. So that'll save you some money. Keep looking. As you've seen in this thread people seem to really like the BHC caps, so they might be a safe bet. There's a few different types of them to choose though.
Highly recommended, do you need them? No. That site also say's they need to be placed as close to the amplifier itself to be most effective, thereby bypassing wiring inductance. So they are already where they matter most, being included on the module itself, you can forget about them.
Bleeders, without them, the caps will maintain a lethal charge looooong after the amp is unplugged, weeks.. months. So they're there to bleed the charge down slowly and fully drain them.
It helps keep them happy as well because without it, the cap's voltage rating stands a chance at reforming to a lesser value over time, obviously this can become dangerous, you could turn it on one day and have it explode.
You're chosen VA rating is just a little on the overkill side, perfect 🙂 Difference from 1000VA to 1200VA... probably price only.
Rectifiers... not two transformers, two secondaries. With two transformers you can have 4 seperate secondaries and 4 full bridge rectifiers. 🙂 People seem to like using this method alot.
It fully decouples the supply from the secondary windings and for any given type of rectifier doubles current capability. You can't really use this if your secondaries are center tapped, so make sure they aren't.
If you buy the cheaper screw down..monolithic rectifiers, you can easily take one out if you dont' like it, definitely plan on by passing them however many you wind up with!
You know the only time I've heard THX certification is in theatres and the sound makes me want to puke. I think they buy the smallest systems they can and overdrive the hell out of them. Poor speaker arrangements too.
Which goes to show you, having the best parts in the world won't make a lick of difference if improperly implemented, so it's worth researching things like layout and wiring techniques for instance.
Fun stuff or what? Hope this helps ya, I think you're off to a good start now, but there is much research to be done yet, so good luck.
Regards
I think you got the cap size right on, didn't verify the math or anything but your method and reasoning seems sound, and so does the answer.
Good news, it's been said with good authority that black gate PSU caps are junk, they dont' share the same high quality sound their smaller (de)coupling/small signal caps do. So that'll save you some money. Keep looking. As you've seen in this thread people seem to really like the BHC caps, so they might be a safe bet. There's a few different types of them to choose though.
Highly recommended, do you need them? No. That site also say's they need to be placed as close to the amplifier itself to be most effective, thereby bypassing wiring inductance. So they are already where they matter most, being included on the module itself, you can forget about them.
Bleeders, without them, the caps will maintain a lethal charge looooong after the amp is unplugged, weeks.. months. So they're there to bleed the charge down slowly and fully drain them.
It helps keep them happy as well because without it, the cap's voltage rating stands a chance at reforming to a lesser value over time, obviously this can become dangerous, you could turn it on one day and have it explode.
You're chosen VA rating is just a little on the overkill side, perfect 🙂 Difference from 1000VA to 1200VA... probably price only.
Rectifiers... not two transformers, two secondaries. With two transformers you can have 4 seperate secondaries and 4 full bridge rectifiers. 🙂 People seem to like using this method alot.
It fully decouples the supply from the secondary windings and for any given type of rectifier doubles current capability. You can't really use this if your secondaries are center tapped, so make sure they aren't.
If you buy the cheaper screw down..monolithic rectifiers, you can easily take one out if you dont' like it, definitely plan on by passing them however many you wind up with!
You know the only time I've heard THX certification is in theatres and the sound makes me want to puke. I think they buy the smallest systems they can and overdrive the hell out of them. Poor speaker arrangements too.
Which goes to show you, having the best parts in the world won't make a lick of difference if improperly implemented, so it's worth researching things like layout and wiring techniques for instance.
Fun stuff or what? Hope this helps ya, I think you're off to a good start now, but there is much research to be done yet, so good luck.
Regards
Backing up most of Chris's comments and opposing one: bleeders are a waste of time IMO as the amp modules will drain the caps down in quick enough time.
You need to limit yourself to a 40 or 42 volt secondary transformer as the max voltage of the modules will be exceeded with 45 volt.
You need to limit yourself to a 40 or 42 volt secondary transformer as the max voltage of the modules will be exceeded with 45 volt.
Running off batteries is a waste of time IMO. It's much cheaper to build a conventional PSU than get the necessary stack of batteries required for the voltage. The batteries will not have anything like the same impedance either, unless you get very expensive/large ones. They will also take up a lot of room, be impractical and probably measure negative on the WAF scale 😉
Through the input resistors huh, I guess in this case it would be a waste of time, but it still can't hurt right? Would make life easy/safer if the urge to test the PSU without modulators attached should ever arise. Like the first time it's ever powered up for instance.
Yeah, I meant to add that about the secondary voltage as well, but I totally forgot, thanks for catching that, I only commented on the VA rating and neglected the voltage.
You need to calculate the secondary voltage allowing for a 10% mains overvoltage condition while unloaded/idle according to the transformers regulation factor, which is probably ~5% for a 1000VA, so a total error of 15% worst case. This total should not exceed 67 volts DC as that's when overvoltage protection kicks in on the new modules (it used to be 63Vdc).
Regards
Yeah, I meant to add that about the secondary voltage as well, but I totally forgot, thanks for catching that, I only commented on the VA rating and neglected the voltage.
You need to calculate the secondary voltage allowing for a 10% mains overvoltage condition while unloaded/idle according to the transformers regulation factor, which is probably ~5% for a 1000VA, so a total error of 15% worst case. This total should not exceed 67 volts DC as that's when overvoltage protection kicks in on the new modules (it used to be 63Vdc).
Regards
Haven't seen a drawing for this yet. I only know how to do it with 1 supply, 2 secondaries, and one or two bridges.
I like the sound of four... I like current 😀
I'm looking out for capacitors. I'll visit some electronics shops soon and report what I can get.
Oh, about the bleeder resistors, what type?
What would happen if I power up a PSU without a load & without resistors?
classd4sure, you've been a great help so far, thanks!
Nothing would happen if you power up a PSU that is not connected to any load. The capacitors would remain charged for many hours, that is all. If you think you will be clumsy enough to put your sweaty hand across both terminals after powering up for the first time without an amp connected then simply connect a bulb there when powering off and wait the few seconds until it goes out. Adding a bleeder simply wastes capacity that the amp could be using and serves no purpose whatsoever when the amps are connected to the PSU as the amps themselves will drain down the caps.
As for the PSU:
As for the PSU:
An externally hosted image should be here but it was not working when we last tested it.
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