After all's been said and done... Did the Sonic Impact T-amp live up to the hype?

[Nuuk]

except the "buy 2 charlize" part.

Sorry, I meant to say 'two for each room'! 😀

 

[mmm12dna]

thanks

thanks nuuk... 😀

the chance for me to listen to it stock is zero... sorry Yeo...

I know what Elna Cerafine sounds like and the balck Gates... i have tons...;-)

My PHY drivers are sounding more supple than what I though they could be.... I am still trying to break them in.... can't wait forever...

Phy, to my supprise, is very gentle at midrange and the high is very smooth.... so more Black gate the better....

and BG caps take one thousand hours to settle down...



But I listen to them after few hundred hrs anyway...

I got all the parts ready Yeo....!!!!

I just got beck from a protest in Washington DC(I live in IL)!!! there were about one million people there... don't let any other media to tell you anything differently...

 

[Nuuk]

I just got beck from a protest in Washington DC(I live in IL)!!! there were about one million people there... don't let any other media to tell you anything differently...

If that was about the same thing they protested about in London yesterday, you may care to know that the official attenence in London was 10,000 but those that were there said it was 100,000! 😉

 

[mmm12dna]

I saw a sign that says. "we should bomb Texas. It has oil too"... 😱

peace..

 

[ChuckT]

Hi DonJuan.

There is a +5Vgen pin that supplies 5V to another 5V pin (forgot which one or two). Just wondering if you have try to supply your own 5v to those pins.

 

[DonJuan]

hi chuckt

nope. you don't hv to supply 5v to it. we tapped it within the pcb.

donjuan

 

[ChuckT]

I recall reading a post that the 5V pins are critical and an external supply bring improvement. I couldn't find this post again. So I am guessing it is refering to the 5Vgen pin that supply 5v to the V5D & V5A pins.
Maybe I shall start a new thread on this.

 

[Diatone]

switch on thump on charlize

I have been told by more than one guys that the loud and scary switch on thump of the charlize is caused by the larger than necessary 10uf input cap, and changing to something smaller like 2.2uf does not affect the sound much and take a large part of the "pop" away.

Has any one testified this?

 

[Nuuk]

Yes, you will get some switch on noise even with smaller caps. But it really isn't difficult to make a 'soft-start' for these amps (as shown on the DiyParadise site or Decibel Dungeon). 😉

 

[KeithC]

I don't get a 'loud and scary thump' from my (unmodified) Charlize at switch on - regardless of psu - just a quiet click. Feel quite left out. Possibly other causes than psu, cct of input device maybe, or x over - mine's fed directly from RCA out of a Benchmark DAC1, and feeds Lowther single drivers.

Feel quite left out.

 

[Nuuk]

I don't get a 'loud and scary thump' from my (unmodified) Charlize at switch on - regardless of psu - just a quiet click. Feel quite left out. Possibly other causes than psu, cct of input device maybe, or x over - mine's fed directly from RCA out of a Benchmark DAC1, and feeds Lowther single drivers.

Poor Keith! Can you find yourself a really old mains switch? That should help! 😀

 

[KeithC]

Mains switch! Damn, why didn't I think of that!.

I rarely box up units as I prefer to connect direct to board, and even more rarely switch things off. So everything is plugged together, with the supply connected firstly from ups socket to conditioner, then conditioner to smp or analog convertor, then from convertor to amp. Any total switch off is done from ups front panel.

i think I have a switched 4 way somewhere, if I plug it in after the conditioner I can join in the fun

 

[Finnegann]

Finally someone else, who doesn't use a mains switch!

 

[KT]

I don't get a 'loud and scary thump' from my (unmodified) Charlize at switch on - regardless of psu - just a quiet click. Feel quite left out. Possibly other causes than psu, cct of input device maybe, or x over - mine's fed directly from RCA out of a Benchmark DAC1, and feeds Lowther single drivers.

Feel quite left out.

Keith,

Here's something interesting I notice with my Charlize: when I have my tube preamp powered up before I turn on Charlize, there is just a slight pop on the speakers. When the preamp is off and I power up Charlize, there is a loud, scary pop.

Maybe having the dac (or preamp) powered up in front of Charlize minimizes the pop? I don't know what the mechanics are, but I get the same results every time depending on whether my preamp is on or off.

The preamp has 2.0uF output caps, btw.

Best,
KT

 

[etsang3]

Hi I helped my friend to replace the original Elna ecap with
obbligato 2.2uF copper cap and the pop sound was gone.
The audio performance was improved also. (very good in playing jazz)

I have done the measurement on the amp. Here is the result and the waveforms recorded.
Idel Current : 13.2V / 90mA
Testing Load : 8 ohm
Voltage Gain : 11.7 (~ 20dB)
Freq.Low = 3.5Hz
Freq. High = 53.2kHz
Max. Power before Clipping is 25.2Vpp (9.9W / 8£[)
and 0.9A is drawn.

===============================================
With reference to 1KHz (10.3 Vpp)
I found freq curve boost up after 5kHz, peek at
20KHz and return to normal at 30KHz.

5kHz = +0.17dB
10kHz = +0.5dB
15kHz = +1.2dB
20kHz = +1.75dB
30KHz = +0.9dB
35KHz = +0.25dB
==============================================

http://i20.photobucket.com/albums/b206/etsang3/IdleHFNoise.jpg
http://i20.photobucket.com/albums/b206/etsang3/F-Low.jpg
http://i20.photobucket.com/albums/b206/etsang3/F-High.jpg
http://i20.photobucket.com/albums/b206/etsang3/Sq-10Hz.jpg
http://i20.photobucket.com/albums/b206/etsang3/Sq-100Hz.jpg
http://i20.photobucket.com/albums/b206/etsang3/Sq-1kHz.jpg
http://i20.photobucket.com/albums/b206/etsang3/Overshooted20.jpg
http://i20.photobucket.com/albums/b206/etsang3/Sq-10kHz.jpg
http://i20.photobucket.com/albums/b206/etsang3/Sq-20kHz.jpg
http://i20.photobucket.com/albums/b206/etsang3/Sq-30kHz.jpg

 

[Panelhead]

Turn on pop

I have moved my modded SI amps to the closet and moved on. My attempts at mounting at 1210 package poly cap and a good pad for offboard film caps did not go well.
The onboard ceramic input caps are responsible for most of the sterile sound and frequency deviations heard on instruments like piano. Getting rid of those ceramic caps will bring a dramatic improvement to all these amps.
I do not think there is a good way to get around the turn on pops. With my Lowthers even the stock ones gave a click. The 2.2 ufd gave a pop, 4.7 ufd gave a thump and crackle. I was too scared to try anything larger. The charging up of the polarizing voltage issue will not go away.
If I was not completely happy with my current amps, a Charlize would be in order though. Extensive work on several SI boards showed that there is a lot to be gotten from mods. Starting with something done right from the start would be great.

George

 

[BWRX]

Re: Turn on pop

Starting with something done right from the start would be great.

I'm working on that 🙂 How about a sneak peek? The board size is about 93mm x 66mm - a little bit bigger than a credit card.