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#71
12-13-2015, 12:19 PM
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3. The whole system:
Do not ask me if a Lamm amp can handle the high gain Shindo VR - so that you can get normal gain situation together with your Avantgarde - I doubt it..... I have to look the specs and especially the input sensivity - how is VR with a line signal matching with your Lamm??? - Let´s say a CD player with 2V output gain??? - If that works than you can move on - of not, you have a compatibility problem between VR and Lamm. You should also have a look to input and output impedances of am and pre. Do not blame us ;-))) - if there is again too much gain....read trough all posts again - it is important, that you understand the whole system with all gain stages.... Yes, you right. VR-Lamm is a weak link in terms of the gain compatibility. VR with CD input (2 mV) does have too much gain, with the volume control on VR at about 8 o'clock position. There is a way to address that, and it was "approved" by Lamm himself - lower Lamm input sensitivity using voltage splitter (just a different value resistor), and that will reduce Lamm gain by about 15 dB, or even more. Lamm input sensitivity is 0.85 dB and most Shindo amps is 1.0 mV, not too much of a difference, and is possible to correct. With regards to a whole Shindo system, it is a commitment, that I' not ready for at this juncture. 
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#72
12-13-2015, 02:36 PM
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Hi Ekki:
The SUTs simply bridge the MC connectors (cartridge) on one side, to the MM phono stage on the other side. And the input impedance of every Shindo pre-amp at the V-R level and above is 100 kOhms here. The Aurieges, Monbrison, and Masseto...and I'm assuming the Partarger are/were 47 kOhms. Vosne-Romanee Here is a schematic of the SUT implementation and the ability to lower the effective impedance, and thus the reflected impedance seen by the cartridge:  My SUT that I made using Lundahl LL1933 modules have two gain settings where the difference in the transformer is whether the primary coils are ran serial or parallel. I can and do load them however I want 1:16 up to ~180 ohms and at 1:8 up to ~600 ohms. I have number of Shinkoh tantalum resistors in different values to adjust my loading within these ranges. Currently with a Denon 103R I am running @ 1:16 with an effective loading of 100 ohms. http://www.lundahl.se/wp-content/upl...heets/1933.pdf You can read an introduction to selecting and setting-up SUT's here. K&K also has calculated resistor values for most of the Lundahl transformers. Kevin @ K&K is about the best person to speak with other than Per Lundahl himself. Kevin is the global expert at selecting and setting up Lundahl transformers. K&K Audio | Moving Coil Step Up Guide mc step-up transformers explained I agree that the total gain through the pre-amp would require us to know the cartridge output -> MC SUT -> MM -> Line stage. But we do know the approximate sensitivity of the MM stage and the output of the cartridge so an approximate step-up ratio, and as you estimated we know about what load the cartridge would like to see. My view isn't looking at total gain. As far as I am concerned the amplifier and speaker sensitivity are irrelevant. I'm trying to look at how the cartridge should be connected via an SUT to the MM input and optimized here. The OP's concern with gain is DIFFERENT. He wanted to adjust his cartridge gain to compensate for the fact that he has 108 dB speakers and a NON-Shindo amp. The easiest solutions are to have a Shindo amp and adjust the gain there... that is what this feature is for in his products. This last part here is my opinion, and other than this I cannot add anything to this discussion. There are many journeys with respect to his overall configuration. But I would not be trying to offset a powerful and/or sensitive amp which is non-adjustable in the way that Shindo amps are, or run crazy sensitive speakers by turning my cartridge down. I agree with everything you conclude with. Best regards, Josh Quote:
Last edited by junker; 12-13-2015 at 03:28 PM.
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#73
12-13-2015, 03:01 PM
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Hi Junker
100Kohm - have you calculated that in your post about the turn ratio???? As you might know all SUT calculation vary with the input impedance of the RIAA stage.... I am not a FAN of loading wether the primary - nor the secondary - and it does not matter if you use a Shinkoh or a normal Vishay - a native SUT with his "natural" loading is in my opinion a lot better regarding the sound. Loading is popular - because it makes one SUT more flexible - but it is not the best way! It is a little bit too complicated and too long to explain here in detail why that is - so sorry for letting things unanswered. If you are more interested in a good read from one of the masters of SUT design - read Dave´s Intact Audio Site - and his forum. Have all a nice day Ekki
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#74
12-13-2015, 03:18 PM
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Yes, here.
http://www.audioaficionado.org/746406-post64.html The physics of a transformer limit the maximum step-up ratio so it is not always possible to achieve the correct load and high step-up ratio. Of course it would be better to have a perfect gain and loading but this often isn't possible without a parallel resistor. Having correct loading is more important than the sound of a parallel resistor. And who makes a 1:23 SUT? This is not practical. Quote:
Last edited by junker; 12-13-2015 at 03:27 PM.
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#75
12-13-2015, 05:08 PM
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"My view isn't looking at total gain. As far as I am concerned the amplifier and speaker sensitivity are irrelevant. I'm trying to look at how the cartridge should be connected via an SUT to the MM input and optimized here. The OP's concern with gain is DIFFERENT. He wanted to adjust his cartridge gain to compensate for the fact that he has 108 dB speakers and a NON-Shindo amp. The easiest solutions are to have a Shindo amp and adjust the gain there... that is what this feature is for in his products. This last part here is my opinion, and other than this I cannot add anything to this discussion. There are many journeys with respect to his overall configuration. But I would not be trying to offset a powerful and/or sensitive amp which is non-adjustable in the way that Shindo amps are, or run crazy sensitive speakers by turning my cartridge down. I agree with everything you conclude with.
Best regards, Josh" I don't necessarily want to adjust cartridge gain to compensate for something else. First of all, speakers sensitivity is irrelevant here, the gain structure of the system is. The main issue in my present setup, is the internal Shindo SUT is not designed for the cartridge as Koetsu with 0.5 mV output (as a matter of fact, for the majority of contemporary cartridges, that have an average output around that value) So, what I' trying to do, following an advise of many here, is to use external SUT with appropriate cartridge, so the combined output will be appropriate for VR MM stage. And this is not to compensate for anything, just to make it appropriate for the VR, so it's MM stage works within the design parameters. As I mentioned before, majority of Shindo own power amps have an input sensitivity of 1.0 V, vs, Lamm's 0.85, which is not a huge difference. Shindo uses adjustable input sensitivity pot to make it more flexible, but the same result can be achieved with lowering Lamm"s input sensitivity, using voltage splitter- same concept, as Shindo, just fixed. I don't think my speakers are not all that different from Shindo own designs- same above 100 dB sensitivity and 16 Ohm impedance. It doesn't seem, there is anything very special about Shindo amps specs, better suited for their own preamps for sure, and apparently voiced accordingly.
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#76
12-13-2015, 05:32 PM
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Okay. Then the answer is simple: for a 0.5v cartridge you would like a step-up ratio of about 1:6 to achieve 3mV. Done. The LL9226 offers an 1:5 (2.5mV) configuration and the LL1931/LL1933 provide for an 1:8 (4mV) configuration. Good luck.
And BTW when you say 1mV input sensitivity that is with the pot at full blast which no one does. Just FYI... Last edited by junker; 12-13-2015 at 05:40 PM.
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#78
12-13-2015, 06:56 PM
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Quote:
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#79
12-13-2015, 07:06 PM
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@Junker and of course @all;-))))
Sut loading is not comparable with resistor loading of an active RIAA stage.... For what do we need loading??? The best would be no loading at all - because loading with a resistor damps our cart. BUT - everyone will agree, that in very, very seldom cases an open MC Cart with no loading sounds good - there are RIAA stages were this is the case - but it is seldom seen. So what do we achieve with loading???? Our RIAA stages deal in a different style with the HF rise coming from our MC cart - with HF rise - I mean not the bump you see often with the frequency charts of your cart - I mean bumps in the region of 30Khz and above, which are not shown in the frequency charts - because they stop at 20Khz. What we think now is - we have to get rid of this HF shit, because it sounds bad - but we do not hear the HF rise directly from the cart - maybe our dogs can hear that, we can´t. But everyone will agree that a cart sounds better if we find the right amount of damping. The problem is - that our RIAA can not deal with the HF rise - we hear the effect of the HF rise through what our RIAA makes out of it. The RIAA has technical problems to handle the incoming HF from our MC cart. It starts to to oscillate and generates a sort of not harmonic distortion -and there are more problems which will be too much to describe here. As higher the capacitance of our arm cable or arm cable with phonocable (if the arm is not wired with a single run of cables) - as worse the HF will do his work with our RIAA stage. So we damp a cart, because we want to make the job for the RIAA stage easier and therefor we get a better sound. No RIAA is equal regarding the HF coming from our cart. And without the knowledge of capacitance of the used cable - tipps and hints of how much damping a cart needed is useless. That is one reason why two High End Freaks can debate days about loading experiences with one and the same cart! In general - transistor stages have more problems with HF coming from our cart than tube stages have - but there are also transistor stages which are constructed in a way, that they can deal with the incoming HF without sounding harsh - an example is the Klayne 7 and the new Willy Bauer RIAA - users of one of the two will tell you, they use their Lyra Etna with no damping at all - putting it directly in a 47 Kohm input - users of a Pass X Ono would cry out loud and argue - that is not possible - because they tried it - and it sounds ugly. More electrical damping (lower resistor figures) mean also we loose output (Lenz´s law!!!!), But also two users with a Klyne 7 might have different experience - in that example we have to ask which arm-cables are used - and what is the total capacitance of them. A transformer is a different animal - maybe you have recognized that you cannot compare damping results with an active RIAA stage with what is going on with a transformer. A DL 103 will sound in most active stages very nice with 400 Ohms loading (read what I have written so far - it is just a common example...) - with a classic DL 103 SUT the DL 103 sees at a RIAA input of 47Kohms 100 Ohm. And the DL 103 does not sound more damped with the SUT, than with the active stage (good transformer is a given fact here). If we would damp a SPU with an active stage to 60 or 50 Ohm, it would sound lifeless and dead - with a classic SPU SUT the cart is damped with around 60 Ohm. The reason for that is - that the SUT "amplifies" the MC signal in a total different way as our active stage does. The SUT has a much larger damping window for a given cart - than the active stage has. Normally we listen with an active stage while trying different resistors to the Treble performance and how fast the cart reacts to the transients of the music - as we also listen to a bloated bass. We try to achieve as much openess and sped as we can get with no harshness in the sound. Sometimes we find with an active stage - that this goal is only reached with only one specified resistor - lets say we think 400 Ohms are nice - 500 is too less the cart starts to get harsh on hot treble parts - like the human S - and with 300Ohm we hear the cart lost speed and agility. With a SUT it will never happen this way - you have a much wider spectrum regarding loading or damping, as with an active stage with the resistor damping. A SUT is not as critical as the active stage. So there is normally no reason to find the sweet spot - because it is not a spot, it is a range! What you do with loading the secondary is not only to get different damping figures with your SUT - you change a lot more in your SUT it gets a different dynamic character as without loading the secondary. I am not afraid of the "sound" of one single resistor - it is absolutely right, that we can not hear this passive element in our signal flow - but the resistor changes not only the damping our SUT gives to the cart - it changes his character - his dynamic character. Try to get rid of the resistor and listen carefully - important is dynamic and micro dynamic. Put it back and listen again........you will recognize a difference - as more you load the SUT down as more difference will be there - this is not subtile, it is dramatic! Let´s say you use a 3 Ohm SUT (1:30) with a Koetsu which needs a 5 Ohm SUT (1:26 - or 1:20) - than you can change the 3 Ohm SUT with resistors that it fits the bill - but it will NEVER sound as good as the 1:20 or 1:26 SUT - NEVER! The dynamic ability is now compromised. The Koetsu sounds like it will make you fall asleep. So it makes much more sense to give a cart a SUT which has a loading window which fits to the cart as loading the secondary to achieve the same figure - but with heavy compromise in the dynamic character of a given SUT. Now coming back to the RIAA stage - if you use a tubed RIAA, than it is again much less sensitive to the incoming HF from our cart, than an active transistor stage. At least matching a SUT to a given cart means to be in a compatible loading window for the cart and have the right amount of gain. Hope that helps Greetings from Berlin Ekki
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#80
12-13-2015, 07:34 PM
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@ Junker
Very nice system GREAT!!!!! - and your example shows, what I tried to explain - if a pre and an amplifier are made for another - means we have a good gain match - than it is no problem to get the volume pots to the section with the best performance - even with highly sensitive speakers - and there is also no impedance mismatch which will cause frequency anomalies. @maril555 Junker shows us here a classic Shindo system - all the elements work perfectly together. And I bet, he also was not born as a Shindo audiophile - but he made a decision, and now he enjoys something which goes in my opinion beyond what HiFi can create...... To the gain story: Think about it - at one point in your VR Ken Shindo managed to get a clean signal with a lot of gain - which is not an easy task!!!!! He tried everything to get a good SN ratio - and he uses for that tubes - that is even a much greater task! In your system you have to throw away all that gain (with a modified Lamm amp) - you damp the Shindo with 15db - Ken would go crazy about that!!!! It is as you buy a Porsche and put a trailer behind the car......you understand what I mean....????? Greetings Ekki
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