It depends on what grade of ceramic mic is specified V what is actually supplied/fitted. Some ceramics are not cheap at all but have good stability and low loss under varying conditions which enables their use in many audio applications. Others may be OK as snubbers in a power supply but that's about all.
Here's some more of the cable tale from Naim to keep you AV watchers amused:
Here's some more of the cable tale from Naim to keep you AV watchers amused:
When I last visited the Salisbury factory (in the 80s) it was like a typical SME building in an industrial area with assembly line and test room. Possibly entirely manual assembly and component sorting. All clean and up to date at the time. You wouldn’t know you were in rural Wiltshire.
I personally don’t recall JV every spouting complete BS. He was very careful what he said; he was not always open, but avoided outright lies. The good old days.
I personally don’t recall JV every spouting complete BS. He was very careful what he said; he was not always open, but avoided outright lies. The good old days.
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Actually, JV said he didn’t need to be too secretive because he discovered that people didn’t tend to take it on board anyhow. He told me stuff that I just didn’t get at the time; I understood the words but why it was important and the mechanisms behind it weren’t obvious to me at all.
I have to respect the engineering savvy and versatility he had. He was previously a sort of car mechanic and he raced Minis for goodness sake. A lover of music he was too.
I have to respect the engineering savvy and versatility he had. He was previously a sort of car mechanic and he raced Minis for goodness sake. A lover of music he was too.
Here is the snapshot of the build. I used SMPS instead of linear power supply and output voltage is 41v DC which is close to recommended 40v DC.
I think that I measured the bias voltage incorrectly. Sorry I am total novice on electronics.
I put positive probe on one end of R29 resistor (red arrow on the attached photo) and negative probe on the other end of R29 resistor (Yellow Arrow) and the DC voltage is 0.5MV on both sides and it does not change when I turn the trim pot at all.
I think that I measured the bias voltage incorrectly. Sorry I am total novice on electronics.
I put positive probe on one end of R29 resistor (red arrow on the attached photo) and negative probe on the other end of R29 resistor (Yellow Arrow) and the DC voltage is 0.5MV on both sides and it does not change when I turn the trim pot at all.
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Good day
Dear Traderbam what you think about:
What happens when DIYers make of clone Naim amps and not have naim sound when work is done ?
I think your story is same with working stories diyers naim,s clones
)Many things in naim amps make for sound
And when you DIY your naim clone your not have of all naim fabric experience and methods and others
Simple amp and schematic but not simple building …
Those pots are multi-turn (often 20-25 turns full travel). Did you keep winding them?
There is not easy to find real schematic. power transistors are not usual type. Also, preamp is related with Naim sound. I've still not tested with real Naim PSU design.
Simple amp and schematic but not simple building …
It could be helpful to know that some of the components in Naim's 250R3 2-channel board shown here are different values or types to those in the early, single channel NAP 250 Board, which most clone boards and cheaper kits seem to follow. That's often published with the kit details of the better clone boards. So, it seems unlikely that a clone kit of the original version using those boards, is going to sound exactly the same as genuine NAP250 products. In any case, there will have been revisions and improvements over some 50 years in production and you won't see those on an early schematics or products.
FWIW, I've assembled and assisted on dozens of different NAP250 based clones and still haven't heard one that comes close to Naim's particular sound quality when assembled according to the schematic or parts overlay. It's a good to see you have fitted what looks like genuine XTX653/753 semis in the VAS though, since these are universal and significant contributors to the original Naim sound.
I've posted this link to Naim schematics, info and DIY clone designs many times. It's old but contains interesting and some useful info buried in the index somewhere: http://www.acoustica.org.uk/t/naim/power_amps.html
FWIW, I've assembled and assisted on dozens of different NAP250 based clones and still haven't heard one that comes close to Naim's particular sound quality when assembled according to the schematic or parts overlay. It's a good to see you have fitted what looks like genuine XTX653/753 semis in the VAS though, since these are universal and significant contributors to the original Naim sound.
I've posted this link to Naim schematics, info and DIY clone designs many times. It's old but contains interesting and some useful info buried in the index somewhere: http://www.acoustica.org.uk/t/naim/power_amps.html
Yes, there's been a compete reworking of the NAP200, 250 & 300 and the addition of DR versions, designed by the new Naim team. They have some obvious features of the early products but as I read it, Steve Sells (ex-Roksan) does the design work and there are videos introducing him as their lead engineer. I have a Nait 5si myself, also designed by Sells but I find its sound quality is distinctly different to earlier Naits 2, 3 and similar small amplifiers like NAP90 which actually made Naim products as popular as they became in the 1980s-2000.
I'm not sure I like the new Nait sound either but I have yet to try it with something more suitable for the higher power than my present speakers.
I'm not sure I like the new Nait sound either but I have yet to try it with something more suitable for the higher power than my present speakers.
Correct The Nait 5i/5i-2/5si have a different sound between old naim sound
My friend Stanislav get Nait5i and listen this
Also connecting Nait1 and NAP250 CB and his say “Oleg the Nait5i have very flat sound and not have naim panch and emotional music stage between old naim Nait one and NAP250/NAC52
But more people’s love the Nait5i/5si
Maybe his not listen old naim maybe not)
P.s the Nait5i/5si a first naim integral amp without preamp. Just volume reg)
But if you connecting in to source NAP without nac preamp you get flat sound)
My friend Stanislav get Nait5i and listen this
Also connecting Nait1 and NAP250 CB and his say “Oleg the Nait5i have very flat sound and not have naim panch and emotional music stage between old naim Nait one and NAP250/NAC52
But more people’s love the Nait5i/5si
Maybe his not listen old naim maybe not
)P.s the Nait5i/5si a first naim integral amp without preamp. Just volume reg
)But if you connecting in to source NAP without nac preamp you get flat sound
)
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Thanks Oleg, for your comments on Nait5 models. It confirms my experience with using a simplified NAC42 clone to increase the input power (i.e. the current) capability for use with my usual music sources that have typical Japanese style RCA line level outputs.
A professional standard line level signal could be up to 3.5V peak to peak but consumer audio gear is usually intended to work with a standard maximum line voltage of 1Vp-p. That's lot of difference if your amplifier is designed for pro. standard input signals and/or has a lower than usual input impedance. So, If our audio output sounds flat, I think it is likely to be an input impedance problem, since we know that there is an adequate signal voltage level available from the source. I've looked at the 5i schematics to find an internal solution but I'm unable to calculate the existing input impedances. I guess I still need a flat +3-6dB buffer inline with the signal source. So, when I get around to trying this out, I'll post a comment, assuming it does improve something about the sound quality.
A professional standard line level signal could be up to 3.5V peak to peak but consumer audio gear is usually intended to work with a standard maximum line voltage of 1Vp-p. That's lot of difference if your amplifier is designed for pro. standard input signals and/or has a lower than usual input impedance. So, If our audio output sounds flat, I think it is likely to be an input impedance problem, since we know that there is an adequate signal voltage level available from the source. I've looked at the 5i schematics to find an internal solution but I'm unable to calculate the existing input impedances. I guess I still need a flat +3-6dB buffer inline with the signal source. So, when I get around to trying this out, I'll post a comment, assuming it does improve something about the sound quality.