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Bgt 29th October 2006 09:10 AM

BTW your NCD's sound really fine, tough to tell the difference with the 400AD. Trying to find them with different music. Some extra burn in hours will help I guess.(have about 100 now)
Think the neighboorhood will start complaning about SPL:D
Forgot its sunday:devilr:

t. 29th October 2006 09:23 AM

Quote:

Originally posted by Bgt
BTW your NCD's sound really fine, tough to tell the difference with the 400AD. Trying to find them with different music. Some extra burn in hours will help I guess.(have about 100 now)
Think the neighboorhood will start complaning about SPL:D
Forgot its sunday:devilr:



:D Thing is Bert I'd expect the NCD to sound a lot better mainly because they cost more than the UCD.
I'll admit my UCD's are sounding soo good at the minute, if I was too upgrade I'd want a noticeable improvement

IVX 29th October 2006 10:16 AM

Bert, 6V@500khz ripple is too much for a ribbon tweeters, which have very little inductance. If you will use claimed features e.g. "The switching frequency is adjustable in the range of 330 to 1000 kHz.", then will >9V@330 ripple, or about 20W@4Ohm continuously. BTW, how implemented interface with ATtiny13, i see no display and no buttons for software control of the switching frequency?

IVX 29th October 2006 10:33 AM

Quote:

Originally posted by Bgt

Lars, sorry, my fault:xeye:
Because I had to switch from 0-1V RMS to 1-10V RMS to get full output the DC content of the generator had to be adjusted.
When I did that it was ok, will make another photo now.
On the UCD I get the output to clip with a level less than 1V RMS.
The NCD needs more. This shouldn't be? 45db should be enough to get full output under 1V RMS?


Hmm..Where you found any words about 45db gain? I see only that -"Input Level 0.9V RMS (200W 8Ohms)" so 40VRMS/.9VRMS=44.4(4) times, but not db's, it's equal 20log(44.4)=33db.:)

soongsc 29th October 2006 11:53 AM

I think the 45db came off the NCD site. I saw it too.

Bgt 29th October 2006 12:08 PM

Quote:

Originally posted by soongsc
I think the 45db came off the NCD site. I saw it too.
correct

Bgt 29th October 2006 12:11 PM

Quote:

Originally posted by t.




:D Thing is Bert I'd expect the NCD to sound a lot better mainly because they cost more than the UCD.
I'll admit my UCD's are sounding soo good at the minute, if I was too upgrade I'd want a noticeable improvement

T, I look at it from a technical&sonic viewpoint, difference in way of designing/sound. If its no better, than yes, cheaper is better.
The UCD's are very robust also.

Bgt 29th October 2006 12:14 PM

Quote:

Originally posted by IVX
Bert, 6V@500khz ripple is too much for a ribbon tweeters, which have very little inductance. If you will use claimed features e.g. "The switching frequency is adjustable in the range of 330 to 1000 kHz.", then will >9V@330 ripple, or about 20W@4Ohm continuously. BTW, how implemented interface with ATtiny13, i see no display and no buttons for software control of the switching frequency?

IVX, how can 500khz do anything with a speaker???? I just cannot imagine this will translate to consumption in the tweeter. Mine is not hot after 4 days of 24h playing.
I don't know about ribbons.

Bgt 29th October 2006 12:17 PM

Quote:

Originally posted by IVX



Hmm..Where you found any words about 45db gain? I see only that -"Input Level 0.9V RMS (200W 8Ohms)" so 40VRMS/.9VRMS=44.4(4) times, but not db's, it's equal 20log(44.4)=33db.:)

You must be right, I think I measured about 1.2V rms for full output for me 100V on the scope. Is about 155Watts.

IVX 29th October 2006 12:23 PM

Quote:

Originally posted by Bgt


correct


Just someone has mismatching with times/db, so your UcD must be little bit louder indeed :)


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