Marmatsouris,
Well, it concerned the mains caps of the PS. Perhaps the ideal value of the caps depends on the size of the transformer?
I'll try the bypass caps. The problem is to integrate these with the shorter wires as possible. If the wires are too long, the benefit could be null...
For the moment i've put a 11Kohm resistor (kiwame) on the input, because my préamp has a very high gain. I'll try to remove it because i've compared the NCD with a "reference" DIY friend's valve amp.
I've not noticed that in highs, the ncd was not so detailed that the valve amp. It is remarquable with violins strings. The texture of the strings are less rich. But this valve amp is very very good!!!
I'll try to post some photos of my amp...
Well, it concerned the mains caps of the PS. Perhaps the ideal value of the caps depends on the size of the transformer?
I'll try the bypass caps. The problem is to integrate these with the shorter wires as possible. If the wires are too long, the benefit could be null...
For the moment i've put a 11Kohm resistor (kiwame) on the input, because my préamp has a very high gain. I'll try to remove it because i've compared the NCD with a "reference" DIY friend's valve amp.
I've not noticed that in highs, the ncd was not so detailed that the valve amp. It is remarquable with violins strings. The texture of the strings are less rich. But this valve amp is very very good!!!
I'll try to post some photos of my amp...
edge540 said:
Hi edge540
The by-pass caps "in theory" will have to be 10% of the value you want to bypass i.e for a 15,000mF cap the by-pass needs to be a 150mF which is impossible to find a good quality MKP of this value. Thus for a real world situation you will have to place a 1% value of the original cap i.e. 15mF which you can again by-pass with a polysterine one at 1.5mF.
With regards to the resistor you have put in series with the input of the NCD1 to lower the gain, i am afraid you have not done it right. You will need an L-Pad arrangement, i.e. one resistor in series and one to ground in order not to upset the circuit.
I believe Lars can help you with the correct values of the resistors.
Kind regards,
Nikos
marmatsouris said:
You 're right Nikos
I've removed these resistors and what an enhancement!!!
They were a filter and now the bandwitch is larger, especialy with bass. It's more live and more subtile.
It's always a good lesson to compare amps, and now with the resistors removed, i'm curious to compare it again...
Roger,
Yes i've changed the chemical caps with black gate's FK. It's difficult to tell you if there was an enhancement because i've mount it with another mods and there is a long period for breaking these. But I think it is benefic.
But the lead-free solve is an horror to desolve
Roger,
Yes i've changed the chemical caps with black gate's FK. It's difficult to tell you if there was an enhancement because i've mount it with another mods and there is a long period for breaking these. But I think it is benefic.
But the lead-free solve is an horror to desolve [/B][/QUOTE]
Hi edge540
What are the "other" mods you have carried out?
Also, the black gate caps you have installed are they the same value/voltage?
Many thanks,
Nikos
Yes i've changed the chemical caps with black gate's FK. It's difficult to tell you if there was an enhancement because i've mount it with another mods and there is a long period for breaking these. But I think it is benefic.
But the lead-free solve is an horror to desolve
[/B][/QUOTE]Hi edge540
What are the "other" mods you have carried out?
Also, the black gate caps you have installed are they the same value/voltage?
Many thanks,
Nikos
Lars,
Could you explain me in what to put a resistor at the input, could have a negative effect. I don't understand but it's evident when you hear!
It was a 11Kohm 5W kiwame.
Yet, i have follow the cookbook in case of a high gain préamp. Only, I din't put the cap because the outputs of my préamp have some.
Could you explain me in what to put a resistor at the input, could have a negative effect. I don't understand but it's evident when you hear!
It was a 11Kohm 5W kiwame.
Yet, i have follow the cookbook in case of a high gain préamp. Only, I din't put the cap because the outputs of my préamp have some.
NCD switching on and off
The NCD modules is switching on and off when using my tube cd-pre.
I have a Audio Aero Capitole cd-pre that is supposed to be connect directly to my NCD amp. The AAC is a tube preamp and have a pretty high voltage on the output. I was thinking about the trick on page 13 in the cookbook where it is advised using a resistor and a cap in series with the input.
Maybe a dumb question, but I am using balanced out/in only, so in order to reduce the inputsignal, how should I go forward in XLR modus? Shall I still use the zobel in series on + wire to the XLR female connector?
Roger
The NCD modules is switching on and off when using my tube cd-pre.
I have a Audio Aero Capitole cd-pre that is supposed to be connect directly to my NCD amp. The AAC is a tube preamp and have a pretty high voltage on the output. I was thinking about the trick on page 13 in the cookbook where it is advised using a resistor and a cap in series with the input.
Maybe a dumb question, but I am using balanced out/in only, so in order to reduce the inputsignal, how should I go forward in XLR modus? Shall I still use the zobel in series on + wire to the XLR female connector?
Roger
Attachments
Hello Roger
You should simply connect a resistor and the DC blocking capacitor in both the + and - inputs. So you need 2 resistors, and 2 capacitors.
Unless your tube preamp (which is unusual) has an effective DC blocking system built in, in which case you don't need the capacitors.
So simply connect the XLR plug as described in the cookbook, but add the resistor and capacitor in both 'hot' wires.
I have sorted things with eric, sorry for the late reply, due to my travelling in the last week, and not being online a lot.
Cheers Lars
You should simply connect a resistor and the DC blocking capacitor in both the + and - inputs. So you need 2 resistors, and 2 capacitors.
Unless your tube preamp (which is unusual) has an effective DC blocking system built in, in which case you don't need the capacitors.
So simply connect the XLR plug as described in the cookbook, but add the resistor and capacitor in both 'hot' wires.
I have sorted things with eric, sorry for the late reply, due to my travelling in the last week, and not being online a lot.
Cheers Lars
Re: Error fixing
So far, so good... Issue has been addressed and solved by Lars. Just waiting for the last parts (Softstart/Filter Combo).
I've just finished installing AutoCad to do some case modeling after drawing some rough sketches with pen and paper.
This is fun as well. Takes a big chunk out of my sleeping hours and whisky supply (everybody here joins in the discussion what art is and should be(…) and minds are more up to this challenge after one or more drinks ;-) ) Still, it's like planning a holiday... pre-fun !!!!
I might also be lucky to have found someone to do the actual CNC work for me. Just have to wait if he is still willing to do so after he has seen my design... ;-)
So, things are going slowly but steady… cheers, Eric.
raintalk said:
So far, so good... Issue has been addressed and solved by Lars. Just waiting for the last parts (Softstart/Filter Combo).
I've just finished installing AutoCad to do some case modeling after drawing some rough sketches with pen and paper.
This is fun as well. Takes a big chunk out of my sleeping hours and whisky supply (everybody here joins in the discussion what art is and should be(…) and minds are more up to this challenge after one or more drinks ;-) ) Still, it's like planning a holiday... pre-fun !!!!
I might also be lucky to have found someone to do the actual CNC work for me. Just have to wait if he is still willing to do so after he has seen my design... ;-)
So, things are going slowly but steady… cheers, Eric.
Good Luck Eric.
I got so used to travelling for extended periods, (40 hours this weekend from Wales to Denmark), that i am now planning a holiday in the autumn, to Western Australia (upcoast on bike, and staying at B&B's). Something to look forward to!
Will bring an e-mail phone of course, so i can be online now and then
I got so used to travelling for extended periods, (40 hours this weekend from Wales to Denmark), that i am now planning a holiday in the autumn, to Western Australia (upcoast on bike, and staying at B&B's). Something to look forward to!
Will bring an e-mail phone of course, so i can be online now and then
Softstart
"-----Original Message-----
From: Lars Clausen [mailto:info@newclassd.com]
Sent: zondag 11 februari 2007 3:17
To: wtfaidh
Subject: Re: NewClassd Dual-Mono Set Soldering Error ???? 20070209
Hello Eric
The soft starts are getting made in the next week, so just about ready.
"
Should be at our doorstep soon (within 2 weeks?)...
"-----Original Message-----
From: Lars Clausen [mailto:info@newclassd.com]
Sent: zondag 11 februari 2007 3:17
To: wtfaidh
Subject: Re: NewClassd Dual-Mono Set Soldering Error ???? 20070209
Hello Eric
The soft starts are getting made in the next week, so just about ready.
"
Should be at our doorstep soon (within 2 weeks?)...
I got tired of waiting for my final PSU parts the other day, and threw together an amp with the single PSU I do have. Given that it's still a far better power supply than my ZAPpulse 2.3SE had, it's a bit unfair to compare the two, but it should come as no surprise that the NCD has it predecessor beaten hands down at just about anything. The tight, warm bass, the precise soundstaging and the relaxed, natural feel to it all are things worth pointing out.
I can't wait to get this amp properly made and hook it up to a more capable CD player.
I can't wait to get this amp properly made and hook it up to a more capable CD player.
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.