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Old 20th February 2014, 06:40 PM   #12111
Salas is offline Salas  Greece
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Originally Posted by rclourenco View Post
Correct, I went for the 43db version. Latter if need I can upgrade or use in-house setup transformers. I will look for the US supplier for the cart.
Better avoid transformers when you will want to try MC or LMC since its only a matter of very few parts changing to convert the FSP for gain. Unless you want to benefit from balanced impedance primary floating transmission. That gives common mode rejection to all the nasty things noise from nearby equipment and mains cables that couple to a strong magnet low signal cart and its single ended cable run. Really good balanced primary SUTs cost much, or are very difficult to self make precisely, interfere a bit also. Still with a 2.5mV 150 Ohm cart like the 10X5 and 43-46dB gain those noise coupling things will be pressed down very low, and its a good source impedance for a JFET to see.
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Old 21st February 2014, 06:54 PM   #12112
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I am looking through my parts bin to find some nice brands of not too big caps and a good in Early voltage and HFE pair of NPNs capable of circa 0.1A bias for a second order classic capacitance multiplier duet on a smallish matrix board to fit near the DC inputs, which is easy to make and test since I just got the simple raw supply with 180mV pk-pk ripple, no RC, no rail extras, but when I disconnect the TT I hear no kind of buzz only mild hiss (mainly from the load resistor, if I short the input 80% goes) with the volume full up. Hmm, I hope it will change something to the better in resolution or ambient cues at least. Or to just interfere with the dynamics, in that case I can keep it for other uses. Its a handy filter cell anyway. Did you manage Kean's low Zout multiplier anybody by now?
As I claimed, I have the exact same phenomenon when I disconnect my TT. Wander too if someone got tested properly build K Multiplier.
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Old 22nd February 2014, 08:11 AM   #12113
Cobra2 is offline Cobra2  Norway
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About the AT 33PTG II; try easing up the load, I had good results with 300-475 ohm, 220 ohm took away some of the fun...(in my system, on another riaa).

Arne K
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Old 22nd February 2014, 11:39 AM   #12114
Salas is offline Salas  Greece
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Originally Posted by Cobra2 View Post
About the AT 33PTG II; try easing up the load, I had good results with 300-475 ohm, 220 ohm took away some of the fun...(in my system, on another riaa).

Arne K
I will give it a go up and down the scale again when it will have 50hrs on it. Got the 300 & 430 Ohm ability too in the DIP switch. TT & rest of system tonal synergy are big factors though. How do you like this cart in general?
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Old 23rd February 2014, 12:35 PM   #12115
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Changed input load to 200ohm, the plan was to see if the midbass could be reduced
Went from 100ohm naked Z-foil to a 200ohm Dahle cmf55

The change was as expected , a little less midbass along with the other disadvantages you could expect going from a excellent resistor to a fairy ok resistor,

The bass peak is less prominent along with some reduced lower bass,
Not good to say how much is because of the change in value VS how much is because of the change in quality.

For those who are interested the CMF55 has some artifacts in the treble (distortion) the sound-stage is smaller and the lower bass is less detailed

Will order 150ohm and 200ohm in naked Z-foil,
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Old 23rd February 2014, 01:19 PM   #12116
AndrewT is offline AndrewT  Scotland
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Use a second metal film resistor in parallel to the cmf55 200r.
Try 200r and 300r to 390r, to hear how it compares.

You could even try 300r metal film and 560r carbon film with the cmf55 to get back to ~100r
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Old 23rd February 2014, 03:01 PM   #12117
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Turbon, it is likely that the rubber suspension in your P8ES has gotten stiff.
I offer a service to replace that rubber with a variety that lasts.
The cartridge also gets retuned.
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Old 23rd February 2014, 03:26 PM   #12118
Turbon is offline Turbon  Sweden
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Originally Posted by Joachim Gerhard View Post
Turbon, it is likely that the rubber suspension in your P8ES has gotten stiff.
I offer a service to replace that rubber with a variety that lasts.
The cartridge also gets retuned.
This is interesting Joachim. Could you PM me some details with price, round trip time and maybe some references

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Old 23rd February 2014, 04:47 PM   #12119
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Old 23rd February 2014, 04:57 PM   #12120
Turbon is offline Turbon  Sweden
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Especially if they have success - I admire them too...
I don't mistrust Joachim but references are always nice. If it turns out as I believe it will I will use him for the coming works I need to be done .

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