panomaniac said:
Pas de soucis, mon ami. Les amplis Italien sont plus chauds, plus amusants que ces amplis scandinaves glacials. Et ca a un gout d'ail. (Je rigole, bien sur)
Let us know how you like the Italians
A comparer avec la chaleur moite des amplis malaysiens !
Sympathique la francophonie à l'autre bout du monde
kanaddict said:
Merci. On n'est pas touts des abrutis par ici.
Sympatique que il y a quelque Francophones sur ces forums.
En effet, ce changement est tres important.
(et maintenant pour nos amis "Anglosaxophones")
Putting in a better input cap will change the sound of the amp. See the thread: Best t-amp capacitors?
For the moment I really like the Obbligatto film/foil. It may not be as neutral as other caps (Auricap, AudioCap) but it sure sounds wonderful. Try it, you'll like it!
The sound from the two Charlizes powering my small Totem speakers is now very sweet, among other desireable adjectives I could throw at it. Beside the benefit of further break-in, I added 28 AWG cotton-insulated braided silver interconnects ($60 from Chris Venhaus) and swapped out the mylar capacitors crossing over the Totem tweeter, both to nice effect. Re the silver interconnects, the dielectric constant of cotton (ie, of cotton+air) is in the range of 1.3 or so, so these interconnects are probably close to state of the art. I plan to build a pair of MTM speakers for this system using Audio Technology 4" woofers ("woofers"), to which I will add a third Charlize to drive each woofer separately and, if amenable, without any crossover component.
By the way, one Charlize drove these 87dB Totem speakers for three hours on Christmas eve to provide dance music through open doors to the back yard deck. Pretty impressive for teeny amp / teeny speakers.
By the way, one Charlize drove these 87dB Totem speakers for three hours on Christmas eve to provide dance music through open doors to the back yard deck. Pretty impressive for teeny amp / teeny speakers.
serengetiplains said:
Why not? As long as the no load or idle voltage doesn't go over 13.5V. Most amps use unregulated supplies.
I think one advantage of these little amps is that they can use a reguated supply. But it should be easy enough to try without. You will most likely end up with lower damping factor and perhaps less dynamic range, unless you have a whopper of a supply. Ripple rejection on these amps is very good, so not ikey to be a big worry.
Hi Pano, I really have little idea how these amps work. I know how they work in general terms, but haven't sufficient understanding to appreciate, for instance, if increased PSU ripple and noise would affect more delicate aspects of the amp's operation (switching and drive circuitry etc). I think overall I favour power supply regulation, though regulation raises that sticky problem of feedback ... two steps forward one step back?
Hey Tom,
I am certainly no PSU expert; I just try to follow what I was taught and what has worked well for me in the past. Your right about the feedback, some folks don't like it anywhere, even in a power supply.
The trouble with an unregulated supply for these amps is getting the voltage right. We only have a range of 8-14 volts in which to work. Below that the amp shuts down, above it may overheat. And as these amps have so little power, we like to push them as near the edge as possible.
So the target voltage range is narrow. In practical terms about 2 volts. Most amps don't have that narrow a window, far from it.
So with an unregulated supply, picking a transformer could be tricky. 9 volts might work, if it didn't go any higher at no load. That would give you somewhere around 12 volts after rectification and filtering.
The chips are supposed to work well off unregulated supplies, but I haven't seen one built that way yet, except for battery power.
It's worth a try!
I am certainly no PSU expert; I just try to follow what I was taught and what has worked well for me in the past. Your right about the feedback, some folks don't like it anywhere, even in a power supply.
The trouble with an unregulated supply for these amps is getting the voltage right. We only have a range of 8-14 volts in which to work. Below that the amp shuts down, above it may overheat. And as these amps have so little power, we like to push them as near the edge as possible.
So the target voltage range is narrow. In practical terms about 2 volts. Most amps don't have that narrow a window, far from it.
So with an unregulated supply, picking a transformer could be tricky. 9 volts might work, if it didn't go any higher at no load. That would give you somewhere around 12 volts after rectification and filtering.
The chips are supposed to work well off unregulated supplies, but I haven't seen one built that way yet, except for battery power.
It's worth a try!
I'm curious to how power supply resistance effects the sound. If regulation creates complications than I suppose a battery supply is ideal. If resistance is a factor, than the obvious solution, if size is not a matter, is to have more batteries in parallel inorder to reduce the resistance. The only disadvantage I see is it is slightly more difficult to obtain a voltage of 13.5 with batteries. Comments?
Nuuk said:
Yes, why not? It shouldn't take more than a minute to try it. You could even put in a selector switch to do an AB comaprison!
Okay, here's an unscientific experiment regarding the SMPS vs. batteries question. I stated earlier that I wasn't realizing an advantage as others had reported by going from a 12 volt battery to a SMPS. Tonight I rigged up a Charlize using the battery with capacitors (6 x 4700uF) ahead of the amp and the SMPS with no capacitance ahead of the amp. I wanted to see if my previous observation of no differences in the two power sources was due to both being run through the bank of capacitors. I put a dpdt switch to provide a seamless and quick means of switching between the two power supplies.
After playing several passages from various familiar CD's that I use to determine imaging and dynamics (ad nauseam), I couldn't determine any audible differences in the two set ups. It appears that the SMPS didn't contribute any additional noise to the very minor amount I detected from my Clarinet preamp that was revealed by the 95dB efficient Horns with FE126E's. I didn't have the SMPS near the t-amp during the testing, so I don't know if it were located in the same chassis that it would introduce noise.
So, it appears that the lone SMPS sonically performs as well as batteries with the capacitor bank. I had the same result driving the less efficient SEAS coaxial TL's.
I have no reason to doubt that the claim of SMPS outperforming batteries sans capacitors is valid. I'm too lazy to rewire the thing to make the battery with no caps comparison; it seems pointless since folks have reported the results of that scenario here.
Thanks Henry,
Good to know stuff like that.
I've "switched" to SMPS too (excuse the pun). I can't hear the difference, at least noise wise. I've also tried to hear if the SMPS is kicking noise back into the AC mains and bothering other gear. So far, it doesn't seem to be.
Unlike most of the guys here, tho, I like the sound of adding big caps. For me it adds dynamics, image stability and width. It most depend on the speakers.
BTW, a number of posts talk about running the power thru big supply caps. That is not exactly what is happening. The caps are in parallel with supply, not in series. In series it wouldn't work! So the power is not going thru the caps, the caps are just a reservoir of power. Thought I should make that clear.
Hara: More batteries would lower the resistance, but would raise noise levels. Don't know if it would raise enough to hurt.
Good to know stuff like that.
I've "switched" to SMPS too (excuse the pun). I can't hear the difference, at least noise wise. I've also tried to hear if the SMPS is kicking noise back into the AC mains and bothering other gear. So far, it doesn't seem to be.
Unlike most of the guys here, tho, I like the sound of adding big caps. For me it adds dynamics, image stability and width. It most depend on the speakers.
BTW, a number of posts talk about running the power thru big supply caps. That is not exactly what is happening. The caps are in parallel with supply, not in series. In series it wouldn't work! So the power is not going thru the caps, the caps are just a reservoir of power. Thought I should make that clear.
Hara: More batteries would lower the resistance, but would raise noise levels. Don't know if it would raise enough to hurt.
W00t!
Got my Charlize this week. First thing I noticed is this thing is small! The enclosure requirements will be small. I was thinking the small alum heatsink enclosure from partsexpress.
http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=262-070
I can't listen to it just yet, still need to design and build the enclosure with all the interconnects and switches. Not to mention, I need to build the speakers.
I'm also looking for some good hook up wire. I need more solder, solder recommendations?
Quick question, in general, are toggle switches and rotary switches are essentially (can't tell difference) transparent (like input selector switches)?
Got my Charlize this week. First thing I noticed is this thing is small! The enclosure requirements will be small. I was thinking the small alum heatsink enclosure from partsexpress.
http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=262-070
I can't listen to it just yet, still need to design and build the enclosure with all the interconnects and switches. Not to mention, I need to build the speakers.
I'm also looking for some good hook up wire. I need more solder, solder recommendations?
Quick question, in general, are toggle switches and rotary switches are essentially (can't tell difference) transparent (like input selector switches)?
A small piece of aluminuim angle, one inch by one inch by three inches long will suffice!
Cat5 solid core for the wire. The best solder IMHO is the one that makes the best joints with your soldering equipment and that is generally found by experience. Of course, you can always follow the hype about any of the over-priced boutique type solders!
Well it depends on the make of the switch but as a genral rule, yes these switches are more transparent than many people would have you believe. Buy a cheap one, build your system and if you feel the need, buy something more expensive later on and see if you can hear the difference!
Nuuk said:
Well it depends on the make of the switch but as a genral rule, yes these switches are more transparent than many people would have you believe. Buy a cheap one, build your system and if you feel the need, buy something more expensive later on and see if you can hear the difference!
Hi,
I bought a cheap one (10$ CND) for my amp and when back to home, I realised that my +2000$ tube amp use the same switch
Regards,