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Old 6th November 2008, 08:27 AM   #181
Thomo is offline Thomo  United Kingdom
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Hi Salas. Many thanks for your help there, I will order some parts in today and also build a jig for matching the fets.

I have basically gone with a moving magnet cartridge (well it's a Grado so it's Moving Iron), because I got it cheap, and I will for now have to use my old SME Series III arm, which is not suitable for a moving coil apparently due to the knife edge bearings used.

I am still very new to vinyl replay, and am pretty much using a TT setup my dad gave me which he hadn't used for around 20 years!

I will report my findings on the phono stage.

Lee.
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Old 6th November 2008, 10:13 AM   #182
RCruz is offline RCruz  Switzerland
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Quote:
Originally posted by Thomo
Hi Salas. Many thanks for your help there, I will order some parts in today and also build a jig for matching the fets.

I have basically gone with a moving magnet cartridge (well it's a Grado so it's Moving Iron), because I got it cheap, and I will for now have to use my old SME Series III arm, which is not suitable for a moving coil apparently due to the knife edge bearings used.

I am still very new to vinyl replay, and am pretty much using a TT setup my dad gave me which he hadn't used for around 20 years!

I will report my findings on the phono stage.

Hi Lee

I am using an SME series II also with knife bearings and it works wonderfully with my MC cart (Benz ACE).

Maybe your series III is too light for the small compliance of the MC cart.... I do not think its imcompatibility is due to the knife edge bearing (These bearings are like dual unipivots)

Look and the Roksan Nima... it is a uinipivot and works perfectly with most MCs....

What make model is your TT ?

Looking forward for your input regardinf fet matching.

Regards

Ricardo
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Old 6th November 2008, 10:17 AM   #183
RCruz is offline RCruz  Switzerland
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Quote:
Originally posted by salas
Hi RCruz,

No, you have a different case. You have a Benz Clear high MC. The MM guys need avoid the input capacitance and need lower sensitivity. The cascode is a necessity for them. It adds more sensitivity to PSU, gets more complex, and yet has to persuade me for any sonic advantages in this kind of phono concept. You need the original circuit you aim at.
Thank you Salas.

I will follow your design very closely.

The PSU I am building uses a very good +25v super regulator (the same I am using in my CDP fet discrete output stage).

I believe It will produce very low noise and big dynamics.

In your first post you wrote you are not aiming to high quality sound but I really hope this RIAA can outperform the stock RIAA I am using in my Meridian 101.

Ricardo
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Old 6th November 2008, 12:28 PM   #184
RCruz is offline RCruz  Switzerland
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Quote:
Originally posted by salas
Thanks! Waiting to see your construction with Miniregs, your choice of components, etc. and learn your sonic experience and comparison to the original Pacific soon!
Hi Salas

How much current does this circuit need ?

I am building a PSU with a spower reg (by sercal) but maybe I could do it with a "softer" low current minireg.
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Old 6th November 2008, 04:19 PM   #185
Salas is offline Salas  Greece
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Hi RCruz, Lee,

Yes I wasn't aiming high, but the ball rolled and the outcome got really good. To the point that I asked for an old, almost non functioning Colin Walker CJ58 TT from a friend with an abused Mission arm, and decided to fix it so to explore beyond my SL1200MKII. Thanks to my good friend Michael and his practical ingenuity, the TT and arm are up, fully restored, Cardas rewired in proper balanced out and correct GND mode, and plays fantastic. Don't underestimate English 80's TT and arm technology or taste. They had a fresh, pacey musical approach that I don't find in many turntable$ of today. Lee is up for a surprise most probably. No CDP can even hint at the natural way of a good TT, warts an all. Just imagine that the record is picked up only, not synthesized from a code. A TT as a whole does 1-2% of mainly even order mechanical distortions and that's all. The signal starts a cm away from the groove as cut by the production, and gets routed directly to the phono pre. The poor CDP has to read well some modulation in an analogue way (like an optic TT), then translate it to a code, then translate again that code into signal, and then filter it! Its a miracle that a good CDP goes as far as it goes today. But its a digital synth, and it will always hint at that fact.

P.S. RCruz, your circuit needs 20mA per channel. (I plan to look for shunt FET DIY reg enhancement to top 317 class performance at a point.)

Click the image to open in full size.

Click the image to open in full size.

Click the image to open in full size.

THANX MICHAEL!
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Old 6th November 2008, 04:28 PM   #186
Thomo is offline Thomo  United Kingdom
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Nice work on the TT there! Those old Mission arms do get good reviews.

My TT is a Technics SL-120. Which was a forerunner to the SL1200's. Although, it does not share the cast resin bass unfortunately. I do believe that with some tweaks though, it could be very good.

Thanks again,

Lee.
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Old 6th November 2008, 07:14 PM   #187
massimo is offline massimo  Italy
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Wow! An original Mission 774 tonearm! Designed by John Bicht of Versa Design.
This should be the mkII version, according by the decoupled counterweight!
No silicon damper? The tank is empty.....

Xάiρω πoλ Kuρiε Salas! Kάλή σπέρά (sorry for the wrong accents)
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Old 6th November 2008, 07:23 PM   #188
RCruz is offline RCruz  Switzerland
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Awesome TT

What cart are you using ?

So you believe that this RIAA is good enough to be built with quality components... (I mean expensive ones) ?

Ricardo
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Old 6th November 2008, 07:27 PM   #189
RCruz is offline RCruz  Switzerland
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Quote:
Originally posted by Thomo

My TT is a Technics SL-120.
Hi Lee

I had one of those.... great bass.... do you have the SME III instaled ?
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Old 6th November 2008, 07:36 PM   #190
Salas is offline Salas  Greece
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Quote:
Originally posted by massimo
Wow! An original Mission 774 tonearm! Designed by John Bicht of Versa Design.
This should be the mkII version, according by the decoupled counterweight!
No silicon damper? The tank is empty.....

Xi o Kui Salas! K * (sorry for the wrong accents)

Nice to see you too. Good evening. No silicone damping because it mates OK with the Denon DL-160 (to answer RCruz too). The paddles in silicone oil bath are useful mainly to avoid bumpy behavior when there is a bad total moving mass and cart suspension elasticity combination. In arms that have that feature, if not needed to be employed, it just rounds resolution for no reason as far as I have experienced in the past. I will make a paper clip paddle and find some proper oil so to be fully restored in any case, bcs a ULM arm can always kick against a better future cart non the less.
The 774 has excellent transients till today, I can attest. I am chuffed.
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