The test signal was a 200mA (=400mA peak-peak) square wave current of 20kHz. A perfect cap will produce a nice triangle wave. ESR will show up as a square wave superimposed on that triangle (the rising and falling slopes of the triangle are off-set by a step function between them). The height of that step, divided by 400mA gives the ESR.JohnW said:
DC bias produced no obvious change to ESR. Temperature however, did. Heating up the cap reduced ESR by a few 10%.
haha!
finished my ucd180 setup today!
No pic's yet... I'll try to post some tomorrow, if i can get a digicam.
My current setup is only for testing purposes. I dont have an adequate transformer yet. Psu bypassing also isn't up to (my) standards yet. Current setup:
22v /225 va (> ~30vdc) transformer
4700uF/63v jamicon / 1000uF 50v bc components (038 series) / 47uF black gate std. / 4,7uF black gate N series in the psu.
At first, it sounded extremely boring. It did everything right (like mark levinson) but it didn't have anything special, no kick, no punch, nothing. Live recordings sounded like studio recordings. boooooooooring. Not musical. After a while it started sounding better.
Right now, it downright outperforms all gainclones i've built. 2 vingers in de neus en gaan met die handel !And that's only after about three hours. With the gainclones i've built i heard improvements right up to two weeks of playing-time. It already has fantastic detail and control in the lower frequencies. It's never struggling to do it right, it 'just does it'.
Strange (but cool) thing: hihats and cymbals and stuff really sound like somebody is hitting something made of metal, not like white noise. Very detailed but not sssssssshhhhh-ish.
.plan:
2x low esr 4700uF 63v (panasonic?)
1x 47uF BG std. 50v
1x 4,7uF BGN 50v.
... per rail
1x 500va dual 33v (amplimo) secondaries (-> ~47vdc) for two channels.
I'll let 'er rip for some time. Maybe, i'll swap the 22uF decoupling caps for something better (black gate? nichicon muse?) and i might change the ne opamp for an ad8620 (with an extra 0,1uF multilayer ceramic cap soldered between + and - directly on the opamp).
After having a few bottles of wine with a couple of friends, my critical listening skills have deteriorated somewhat
drink: ) but still, it sounds pretty good to me. Dead quiet, dynamic, maybe a little analytical and a little less musical but it's still burning in.
This amp really likes live-recordings. Studio-stuff is not it's pakkie-anj (thing).
Strange thing is that one channels runs MUCHO hotter than the other.... Anyone? (jp? bruno?) i'll try to make some measurements...
/matti
finished my ucd180 setup today!
No pic's yet... I'll try to post some tomorrow, if i can get a digicam.
My current setup is only for testing purposes. I dont have an adequate transformer yet. Psu bypassing also isn't up to (my) standards yet. Current setup:
22v /225 va (> ~30vdc) transformer
4700uF/63v jamicon / 1000uF 50v bc components (038 series) / 47uF black gate std. / 4,7uF black gate N series in the psu.
At first, it sounded extremely boring. It did everything right (like mark levinson) but it didn't have anything special, no kick, no punch, nothing. Live recordings sounded like studio recordings. boooooooooring. Not musical. After a while it started sounding better.
Right now, it downright outperforms all gainclones i've built. 2 vingers in de neus en gaan met die handel !And that's only after about three hours. With the gainclones i've built i heard improvements right up to two weeks of playing-time. It already has fantastic detail and control in the lower frequencies. It's never struggling to do it right, it 'just does it'.
Strange (but cool) thing: hihats and cymbals and stuff really sound like somebody is hitting something made of metal, not like white noise. Very detailed but not sssssssshhhhh-ish.
.plan:
2x low esr 4700uF 63v (panasonic?)
1x 47uF BG std. 50v
1x 4,7uF BGN 50v.
... per rail
1x 500va dual 33v (amplimo) secondaries (-> ~47vdc) for two channels.
I'll let 'er rip for some time. Maybe, i'll swap the 22uF decoupling caps for something better (black gate? nichicon muse?) and i might change the ne opamp for an ad8620 (with an extra 0,1uF multilayer ceramic cap soldered between + and - directly on the opamp).
After having a few bottles of wine with a couple of friends, my critical listening skills have deteriorated somewhat
drink: ) but still, it sounds pretty good to me. Dead quiet, dynamic, maybe a little analytical and a little less musical but it's still burning in.This amp really likes live-recordings. Studio-stuff is not it's pakkie-anj (thing).
Strange thing is that one channels runs MUCHO hotter than the other.... Anyone? (jp? bruno?) i'll try to make some measurements...
/matti
Matti,
I have heard it more that the amps will sound better after several hours powered up, it has something to do with the electrolytic capacitors.
In about +/2 weeks we will have our full round toroidel on stock , special designed for one or two UcD180.
Perhaps this is something for you?
One hotter as the other;
Did you mount the UcD180 on a small heatsink, or in free air?
There can be some difference in the idle current, in free air the difference in temperature is much bigger as when you mount it on a heatsink.
When you don't trust we can replace it, no problem!
Regards,
Jan-Peter
www.hypex.nl
I have heard it more that the amps will sound better after several hours powered up, it has something to do with the electrolytic capacitors.
In about +/2 weeks we will have our full round toroidel on stock , special designed for one or two UcD180.
Perhaps this is something for you?
One hotter as the other;
Did you mount the UcD180 on a small heatsink, or in free air?
There can be some difference in the idle current, in free air the difference in temperature is much bigger as when you mount it on a heatsink.
When you don't trust we can replace it, no problem!
Regards,
Jan-Peter
www.hypex.nl
withoud trying to flood this thread (i'll back off ) here a not-so good pic of the amp, with a cd case for sizing comparison. It's a temporary case, threw the clone i wasn't happy with anyway out, put in the amp. pic made with my phone, when i get my final enclosure i'll post another (hq?) pic.
) here a not-so good pic of the amp, with a cd case for sizing comparison. It's a temporary case, threw the clone i wasn't happy with anyway out, put in the amp. pic made with my phone, when i get my final enclosure i'll post another (hq?) pic.
An externally hosted image should be here but it was not working when we last tested it.
I've still a lot of small questions, and hope some have not already been answered elsewhere.
So we're back in analog circuit design.
Is the NE5532 mounted in 8-DIP or in SOIC format? Makes a difference when someone wants to upgrade the opamp. Or can this be done in the factory?
What requirements does the input stage have to fulfill?
As far as I could judge, it seems sufficient that the UCD-module has to see a differential, DC-free low-impedance circuit at his entrance. Designing another buffer/pre circuit without opamps and that meets those requirements would do it, no? Of course I make abstraction of the protection circuit. Please correct me if I'm wrong. Dreaming e.g. of a tube pre gain stage...
Can the 22µF coupling caps be removed when the input signal is DC-free (preamp with output capacitor)?
Isn't it more logical to put those caps at the entrance of the input circuit? The required value could be much lower then (high Z).
And finally, does the circuit require an additional speaker protection circuit, like those Velleman kit's? And what happens if we short-cut the output by inadvertance?
That's all, Folks.
Yves
Bruno Putzeys said:
So we're back in analog circuit design.
Is the NE5532 mounted in 8-DIP or in SOIC format? Makes a difference when someone wants to upgrade the opamp. Or can this be done in the factory?
What requirements does the input stage have to fulfill?
As far as I could judge, it seems sufficient that the UCD-module has to see a differential, DC-free low-impedance circuit at his entrance. Designing another buffer/pre circuit without opamps and that meets those requirements would do it, no? Of course I make abstraction of the protection circuit. Please correct me if I'm wrong. Dreaming e.g. of a tube pre gain stage...
Can the 22µF coupling caps be removed when the input signal is DC-free (preamp with output capacitor)?
Isn't it more logical to put those caps at the entrance of the input circuit? The required value could be much lower then (high Z).
And finally, does the circuit require an additional speaker protection circuit, like those Velleman kit's? And what happens if we short-cut the output by inadvertance?
That's all, Folks.
Yves
Matjans,
I have made you picture a little bit lighter
Small suggestion; turn the modules 90degrees, so that the T are right and left. And put all wires of the powersupply in the centre of the modules and make them some shorter.
Regards,
Jan-Peter
www.hypex.nl
PS I post next week on our website the price of our powersupply for the UcD180.
I have made you picture a little bit lighter
Small suggestion; turn the modules 90degrees, so that the T are right and left. And put all wires of the powersupply in the centre of the modules and make them some shorter.
Regards,
Jan-Peter
www.hypex.nl
PS I post next week on our website the price of our powersupply for the UcD180.
Attachments
Tangui said:I've still a lot of small questions, and hope some have not already So we're back in analog circuit design.
Is the NE5532 mounted in 8-DIP or in SOIC format? Makes a difference when someone wants to upgrade the opamp. Or can this be done in the factory?
J-P I think you should consider an "audiophile" version of your UCD-modules. I work also in the business so I know it's quite easy to only change same parts. AD8620 is substantially more costly but you can also charge more because those who know what AD8620 is know also that it costs more than NE5532. Those who don't know the difference triggers to the word "audiophile"
Tangui,
The NE5532 is an So8, easier to replace for a better device
Indeed the best would be a DC-free preamplifier with symmetrical output, a tube symmetrical design......that would be a very good I think!
Yes, if you are shure you have a DC-free preamplifier, you can save remove the 22uF coupling caps. I choosed for the coupling caps between the op amp and the ucD modulator, the op amp has a very low outputimpedance so the influence will be quit low.
The UcD180 is protected against low impedance and shortcircuit but there is no DC protection.
Per-Anders,
In a way the UcD is already quite "Audiophile", does the AD8620 sound so much better as other good op amps?
I will put mine mind on a modified UcD180 version......
Regards,
Jan-Peter
www.hypex.nl
The NE5532 is an So8, easier to replace for a better device
Indeed the best would be a DC-free preamplifier with symmetrical output, a tube symmetrical design......that would be a very good I think!
Yes, if you are shure you have a DC-free preamplifier, you can save remove the 22uF coupling caps. I choosed for the coupling caps between the op amp and the ucD modulator, the op amp has a very low outputimpedance so the influence will be quit low.
The UcD180 is protected against low impedance and shortcircuit but there is no DC protection.
Per-Anders,
In a way the UcD is already quite "Audiophile", does the AD8620 sound so much better as other good op amps?
I will put mine mind on a modified UcD180 version......
Regards,
Jan-Peter
www.hypex.nl
My amp is almost ready to rock...
Some pics...
I´ll be back with more pics and an evaluation of the sound...
/Stefan
Some pics...
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
I´ll be back with more pics and an evaluation of the sound...
/Stefan
oewaaaaaa !!
i'm a a very happy camper right now !
swapped the transformer for a 4x15v secondaries 500va i borrowed from a friend of mine. wired two secondaries in series to give me ~30vac which, after rectification, gives me +/- 43vdc.
remember the "poef" i mailed you about jp? Well, it's here. Hello music!
At first, my amp sounded slightly boring, like the musicians weren't trying their best, they just 'did another gig'.
Sounds more than fine to me now!
i'm a a very happy camper right now !
swapped the transformer for a 4x15v secondaries 500va i borrowed from a friend of mine. wired two secondaries in series to give me ~30vac which, after rectification, gives me +/- 43vdc.
remember the "poef" i mailed you about jp? Well, it's here. Hello music!
At first, my amp sounded slightly boring, like the musicians weren't trying their best, they just 'did another gig'.
Sounds more than fine to me now!
Some more pics...
Soft start:
Connections and on/off
Overview:
/Stefan
Soft start:
An externally hosted image should be here but it was not working when we last tested it.
Connections and on/off
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
Overview:
An externally hosted image should be here but it was not working when we last tested it.
/Stefan
peranders,
as i understand, NE5532 isn't minimal cost choice at all, but quite costeffective choice suitable for buffering. I tried lm833 and was surprised by the worse transparency vs modulator itself. Although it's very interesting about sounding AD8620 (and many others sorted by rating) as UcD buffer.
as i understand, NE5532 isn't minimal cost choice at all, but quite costeffective choice suitable for buffering. I tried lm833 and was surprised by the worse transparency vs modulator itself. Although it's very interesting about sounding AD8620 (and many others sorted by rating) as UcD buffer.
NE5532 isn't that bad but unfortunately I have never done a good test between opamps. I have tested a 741, 4556(?) and NE5534 in a phono amp and the difference was dramatic but I'll imagine that AD8620 is one tiny bit better than 5532 but I have never tested this having those opamps side by side.
Some other question: What is the estimated price for the UCD400?
Can I expect a slight worse performance for the 400 watt module compared to the 180 watt one? Normally low voltage amps are better than high voltage/ high power amps.
but I'll imagine that AD8620 is one tiny bit better than 5532 but I have never tested this having those opamps side by side.Some other question: What is the estimated price for the UCD400?
Can I expect a slight worse performance for the 400 watt module compared to the 180 watt one? Normally low voltage amps are better than high voltage/ high power amps.
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