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Overall freq. response *that* bad? - Click HERE for Original Thread
Onvinyl
Hi,
I made a few measurements:
first: Sweep from CD-> Voltage divider -> phonopre -> amp -> PC Soundcard
Looks like that:

please consider that linear (inside about 0,3dB), the differences at the edges are due nonlinearities of CD->amp->Soundcard loop

Now a triangle @ 1kHz of the cardas Test LP
Sweep from LP-> DL103/SME3009/TD125MKII -> phonopre -> amp -> PC Soundcard:

Not that bad, I'd say.

But now the cardas sweep from 30Hz - 30kHz looks like those tiny little creatures I saw last time in schools biology lesson:


I'd never thougt that this could be that bad!

The loudest part is around 14kHz, then suddenly falling

Is something wrong here? Normal? Anything else?
Rüdiger
Werner
The frequency sweep on the HFN test record is equally useless. I also have the Cardas, but haven't found the time to try it. Your images make me desparate, though.

Try a pink noise track and use a lot of smoothing. That gives results much more in line with what you'd expect.

Ah, you could also try the Cardas at 45rpm. If the frequency anomalies scale with speed they are on the record. If they remain in place they are in the replay chain.
Ouroboros
Is this really any worse than you would expect from a moving-magnet cartridge? The tip-mass resonance looks a bit low but that's all.

It is vinyl playback for heaven's sake! You can't expect too much from it, although it would be interesting to see the response using a good moving-coil cartridge.
Onvinyl
Hi Ouroboros,
as I wrote, it is a Denon DL103 MC-Cartridge, which is not high end, but certainly we do not see the datasheets flat respons from 20Hz to 40kHz...

@Werner: I will certainly try it at 45RPM

Rüdiger
Werner
A DL-103 measures quite flat. See here:



These are response and channel separation for a pink noise track. You have to compensate mentally for the -3dB/oct droop of the noise.


Doing so with different software fooled into thinking that the output of the cartridge is the response to the input generated by the sound card (which it obviously isn't) yields this: cheap old MM top, DL-103 bottom. Much more ragged, most probably due to the lack of synchronisation between input and output.





Incidentally, the 103 measures excellent in all respects. It is almost as flat as my Allaerts, has almost the same channel seperation, and one particular sample of 103 even had less distortion.
Onvinyl
Werner,
thanks for the instructive cartridge measurements. How was the test setup?

Rüdiger

edit: spelling
Werner
HFN test record with pink noise track, turntable/cartridge (Technics SL-D2 in above pix), phono pre (probably Rotel 970, don't remember), sound card (Terratec Phase 26 with heavy mods to compensate for Terratec design engineer's incompetence, end-of-rant), PC.
Demo Audition used to record and off-line spectral analysis, demo S-lab configured for real-time analysis with pink noise out/in.
Onvinyl
It's the sweep. The maximum is now at 18kHz.







I go and get me another test record, maybe I can find the HFN or somthing similar,
Rüdiger

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