barfind said:I am very happy with the amp with caps out. Each to their own, but I could not live with this amp with the caps in 🙂
Nigel
Are you guys talking about the cap across the power supply rail, or the input/output signal caps?
Thanks,
KT
hi KT
We're talking Rail - adding capacitance to improve current delivery. but large caps tend to be slow. That's why they get paralleled with small value caps.
Large capacitance does not guarantee fast current delivery.
This is speculation on my part but I'll give it a shot anyway:
Take a cap and measure the voltage as it is charging. Time how long it took to charge and that will be the current delivery speed for that cap.
We've been talking about Charlize who at max I've only seen her draw .5 amps - Why would you need 10000uf ? Only if you PS can't deliver .5 amps or if your supply is dirty and you need to clean it up some more.
In my setup no matter what type of PS I put in front of Charlize, she always sounds clean.
So she does a great job at rejecting garbage from cheap PSU's.
The coloration and timing effects apply even more to the input and output caps.
Bachiano
We're talking Rail - adding capacitance to improve current delivery. but large caps tend to be slow. That's why they get paralleled with small value caps.
Large capacitance does not guarantee fast current delivery.
This is speculation on my part but I'll give it a shot anyway:
Take a cap and measure the voltage as it is charging. Time how long it took to charge and that will be the current delivery speed for that cap.
We've been talking about Charlize who at max I've only seen her draw .5 amps - Why would you need 10000uf ? Only if you PS can't deliver .5 amps or if your supply is dirty and you need to clean it up some more.
In my setup no matter what type of PS I put in front of Charlize, she always sounds clean.
So she does a great job at rejecting garbage from cheap PSU's.
The coloration and timing effects apply even more to the input and output caps.
Bachiano
Hi All,
I'm looking for one good psu for my autocostruire kit, so what you think about these psu's below:
http://www.radioshack.com/product/index.jsp?productId=2103959&cp=&kw=power&parentPage=search
http://www.autocostruire.com/catalog/product_info.php?cPath=42&products_id=264
Any other good choice?
Cheers,
Alexandre.
I'm looking for one good psu for my autocostruire kit, so what you think about these psu's below:
http://www.radioshack.com/product/index.jsp?productId=2103959&cp=&kw=power&parentPage=search
http://www.autocostruire.com/catalog/product_info.php?cPath=42&products_id=264
Any other good choice?
Cheers,
Alexandre.
amolan said:Any other good choice?
Cheers,
Alexandre.
Check out some extra regulator boards I'm selling here.
You would still need to add a transformer and bridge rectifier (or get yourself a higher voltage and current wall-wart to supply the unregulated DC input) but could make a nice adjustable, regulated supply with that board and about $15USD in parts plus your time to solder the parts onto the board.
That's a bit cheaper than $59USD for the Autocostruire PSU and could have a higher current capability than the Radio Shack unit.
I can even write up a digikey parts list of the components I used on my boards if you're interested.
Brian
Hi Brian,
Thank's for your offer but I have no skills to do it, I need a assembled solution.
Alexandre.
Thank's for your offer but I have no skills to do it, I need a assembled solution.
Alexandre.
I am still awaiting my goodies from Apexjr via snail mail, hopefully they will be here by the weekend.
I have not heard much change in Charlize. The only change is in me, I am now wondering why should I bother with building tube stuff anymore.
A quick comparison with my SE 807 amp and the 807 is a bit "richer" sounding in the mids but the tube is not as clear and dare I say honest as Charlize.
I think I am smitten by her!
Andrew
I have not heard much change in Charlize. The only change is in me, I am now wondering why should I bother with building tube stuff anymore.
A quick comparison with my SE 807 amp and the 807 is a bit "richer" sounding in the mids but the tube is not as clear and dare I say honest as Charlize.
I think I am smitten by her!
Andrew
This is Scary
I think I'm feeling the same thing
Although I have to say that after puttting a tube preamp in front of Charlize I'm even Happier.
But then again - That might be an indication that I need a better source.
Bachiano
I think I'm feeling the same thing

Although I have to say that after puttting a tube preamp in front of Charlize I'm even Happier.
But then again - That might be an indication that I need a better source.
Bachiano
How long have you guys burned in your Charlize amps for? And what kind of speakers are you using?
I am running a Charlize with a tube pre, and I have noticed some change to the sound with about 60 or 70 hours on it so far. I'm hoping that it will settle in further because although it sounds very, very good, I don't feel that it's quite there, yet.
It's amazing how good it sounds considering the module is only around $90, though.
KT
I am running a Charlize with a tube pre, and I have noticed some change to the sound with about 60 or 70 hours on it so far. I'm hoping that it will settle in further because although it sounds very, very good, I don't feel that it's quite there, yet.
It's amazing how good it sounds considering the module is only around $90, though.
KT
I have maybe 50 hours or so, the speakers I use etc are in my original post which started this thread. I am now using an SMPS from a computer and awaiting 2 more.
Andrew
Andrew
KT said:How long have you guys burned in your Charlize amps for? And what kind of speakers are you using?
I am running a Charlize with a tube pre, and I have noticed some change to the sound with about 60 or 70 hours on it so far. I'm hoping that it will settle in further because although it sounds very, very good, I don't feel that it's quite there, yet.
It's amazing how good it sounds considering the module is only around $90, though.
KT
I use a tube pre as well. This setup sounds awsome on my B200 OB's
Nigel
What is it about the tube preamp that we like???
As I said before.
"puttting a tube preamp in front of Charlize I'm even Happier.
But then again - That might be an indication that I need a better source."
So, if we like Charlize, but its a little to bright the tube will soften it a bit.
Or maybe, our source is to bright and the tube preamp softens is a bit as well.
It will be interesting to try various sources to see if the preamp is really needed.
Another thought is that originally I ran Charlize straight with just a 100k pot.
When I added the Preamp; "IT" has a 10K pot.
I've notice that there is a sweet spot for both pots.
Charlize's pot is set 50% open and the preamp is set 60% open.
This give me the best presence from the combo.
So, I think this may be an issue of matching impedance and not necessarily of the preamp sounding better.
Bachiano 😕
P.S. I've heard that charlize's input impedance may be around 20kohm. is this correct???
As I said before.
"puttting a tube preamp in front of Charlize I'm even Happier.
But then again - That might be an indication that I need a better source."
So, if we like Charlize, but its a little to bright the tube will soften it a bit.
Or maybe, our source is to bright and the tube preamp softens is a bit as well.
It will be interesting to try various sources to see if the preamp is really needed.
Another thought is that originally I ran Charlize straight with just a 100k pot.
When I added the Preamp; "IT" has a 10K pot.
I've notice that there is a sweet spot for both pots.
Charlize's pot is set 50% open and the preamp is set 60% open.
This give me the best presence from the combo.
So, I think this may be an issue of matching impedance and not necessarily of the preamp sounding better.
Bachiano 😕
P.S. I've heard that charlize's input impedance may be around 20kohm. is this correct???
P.S. I've heard that charlize's input impedance may be around 20kohm. is this correct???
If you are using an active stage AFTER the pot/attenuator, that sets the output impedance of the pre-amp, ie it isolates the pot.
If you are using one of the NOS DACs, it is better to use a pot/attenuator with an impedance of 20K or higher!

tube preamp output impedance
"If you are using an active stage AFTER the pot/attenuator, that sets the output impedance of the pre-amp, ie it isolates the pot"
My preamp has two Outputs one 10K and the other 800 ohm.
I'm using the High impedance now ( cause I was driving some old Altecs El34s )
but I'll try the low as soon as I can.
"If you are using one of the NOS DACs, it is better to use a pot/attenuator with an impedance of 20K or higher! "
No - Not using NOS DAC but getting one soon - so I'll Keep that in mind.
"20k or higher" How much higher? and Why?
Thanks
Bachiano
"If you are using an active stage AFTER the pot/attenuator, that sets the output impedance of the pre-amp, ie it isolates the pot"
My preamp has two Outputs one 10K and the other 800 ohm.
I'm using the High impedance now ( cause I was driving some old Altecs El34s )
but I'll try the low as soon as I can.
"If you are using one of the NOS DACs, it is better to use a pot/attenuator with an impedance of 20K or higher! "
No - Not using NOS DAC but getting one soon - so I'll Keep that in mind.
"20k or higher" How much higher? and Why?
Thanks
Bachiano
Re: tube preamp output impedance
Hi,
I use a 25K stepped attenuator and the result is very good.
I don't feel the need to put an active preamp in front of Charlize.
With the 25K pot, it sound as good as my tube amp (Rogue Tempest Magum with KT-90 type II).
Regards,
Daniel
bachiano said:"
"20k or higher" How much higher?
Bachiano
Hi,
I use a 25K stepped attenuator and the result is very good.
I don't feel the need to put an active preamp in front of Charlize.
With the 25K pot, it sound as good as my tube amp (Rogue Tempest Magum with KT-90 type II).
Regards,
Daniel
20k or higher" How much higher? and Why?
Yes, as Daniel says, 25K seems to be fine and that's what I use too. But I do find that Charlize doesn't work as well fed directly from the 25K attenuator as she does with a buffer between them!

KT said:I am running a Charlize with a tube pre, and I have noticed some change to the sound with about 60 or 70 hours on it so far. I'm hoping that it will settle in further because although it sounds very, very good, I don't feel that it's quite there, yet.
The more Charlize burns in the more impressed I am with it.
Just a few days ago it reached a point where some of the cloudiness cleared up, but then there was a slight thinness to the sound as well as a subtle but irritating tizziness in the treble. Also, the whole frequency range hadn't jelled - a little incohesive.
Today I can tell these things are working themselves out. The tizziness is much reduced and the sound has integrated to a point where I can relax to it. I think it still has a bit of burn-in, yet, but it's much better today. It's doing things very well, but I think it needs to reach a point of better cohesion before it matches the Gaincard - can and will it get there?
I agree with Nick that the sound is not quite as emotionally invovling as a Gaincard/Gainclone. The Charlize does do that Tripath psychedelic detail thing very well, though. I'd say this effect on the Charlize is not as captivating as on a modified Sonic Impact T-amp, but the Charlize is much better balanced and much more listenable than the SI T-amp overall. I'd say the Charlize sound falls somewhere between the Gaincard and the SI T-amp.
We'll see how it settles as it burn in more, but what a great deal this amp is!
Best,
KT
Hi Guys,
I will use Charlize without preamp, and I'm already have a alps pot 50k, it's ok ?
Thanks,
Alexandre.
I will use Charlize without preamp, and I'm already have a alps pot 50k, it's ok ?
Thanks,
Alexandre.
I will use Charlize without preamp, and I'm already have a alps pot 50k, it's ok ?
You can try it Alexandre - it won't do any harm. But I suspect that you won't be hearing Charlize at her best! 🙁
Without a buffer stage, I wouldn't want to go higher than 10K for the attenuator/pot!

KT, at the risk of de-railing the whole class-T thing, I have to say that I have gone back to my Gainclone and quite honestly enjoy it more than any of the class-T amps, even if it is not as good in some ways, it is just more enjoyable! 😱
I'm looking forward to trying the class-T's with a valve pre though, so the motto here is 'never say never'! 🙂
Got my "goodie box" from the Post awhile ago. The SMPS that I got from Apexjr is from here.
This is the link to the page with all the specs.
http://www.cosel.co.jp/en/products/lda/pe_lda75f.html
This is the link to the page with all the specs.
http://www.cosel.co.jp/en/products/lda/pe_lda75f.html
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