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Other Stuff => Archived Manufacturer Circles => Hagerman Technology => Topic started by: jupiterboy on 30 May 2015, 02:45 pm

Title: Piccolo2 Output Impedance
Post by: jupiterboy on 30 May 2015, 02:45 pm
Remedial question, but how does the output impedance relate to the following phono amp? How does one determine a good match on paper?
Title: Re: Piccolo2 Output Impedance
Post by: poty on 1 Jun 2015, 08:37 am
I can't fully answer to this question, because there are a lot of possible versions of such interconnects, but I guess the Piccolo is designed with the "standard" 47kOhm load in mind (certainly changed in some usual way by an interconnect cable).
Title: Re: Piccolo2 Output Impedance
Post by: hagtech on 3 Jun 2015, 06:01 am
The output impedance of a PICCOLO2 is around 300 ohms.  That's low enough to drive just about anything but headphones.  Certainly no problem when loaded by a 47k phonostage.

jh
Title: Re: Piccolo2 Output Impedance
Post by: jupiterboy on 3 Jun 2015, 03:56 pm
Thanks guys. Jim, would you run into any issues using alternate loadings on the phono pre if you wanted to acheive a different loading? I can get 100K, 62K, 50K, 38K, 2K and 1K.
Title: Re: Piccolo2 Output Impedance
Post by: poty on 4 Jun 2015, 07:00 am
Thanks guys. Jim, would you run into any issues using alternate loadings on the phono pre if you wanted to acheive a different loading? I can get 100K, 62K, 50K, 38K, 2K and 1K.
This question has been discussed (in the previous version - Piccolo). I'm not native speaker so correct me please if I understand your question wrong: would you like to use different values for R3? It's OK, no issues.
Title: Re: Piccolo2 Output Impedance
Post by: jupiterboy on 4 Jun 2015, 06:08 pm
Thanks for the response. To clarify, I am talking about loading values on the phono preamp rather than the piccolo head amp.
Title: Re: Piccolo2 Output Impedance
Post by: poty on 5 Jun 2015, 01:35 pm
Thanks for the response. To clarify, I am talking about loading values on the phono preamp rather than the piccolo head amp.
Sorry for misinterpretation... Well, why should you use the switching loadings then after the head amp? They (the different loadings) will not influence the input of Piccolo, so the only question is - what are you trying to achieve?
Title: Re: Piccolo2 Output Impedance
Post by: jupiterboy on 7 Jun 2015, 10:43 am
Full circle, back to the original question. I assume the spec was mentioned for a reason, and thought I might learn something. It would be about the handshake between the head and phono pre though. Nothing much to do with the cart. I know with my preamp I usually look at the sensitivity spec and the voltage going in.
Title: Re: Piccolo2 Output Impedance
Post by: poty on 8 Jun 2015, 11:06 am
I don't think there is much done on paper. Output and input impedances are only two bricks in the bridge between components.
In this case the input resistance of the phono pre is a great contributor to the noise, but it is usually bypassed by relatively low (~500-5k) cartridge output impedance. Piccolo has almost twice as better values as the best MM cartridge I know, so this is not the case of lowering the input resistance value.
According to the many use cases Piccolo does not have problems with driving low-resistance inputs. The only question left - what is the sweet point in distortions?
Title: Re: Piccolo2 Output Impedance
Post by: hagtech on 10 Jun 2015, 04:38 am
I don't believe there is a "sweet spot" for loading that gives minimal distortion.  It just gradually gets worse as you lower the loading impedance.  That is, 47k will sound a lot better than 47.

jh
Title: Re: Piccolo2 Output Impedance
Post by: G Georgopoulos on 10 Jun 2015, 04:47 am
I don't believe there is a "sweet spot" for loading that gives minimal distortion.  It just gradually gets worse as you lower the loading impedance.  That is, 47k will sound a lot better than 47.

jh

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