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Old 3rd February 2013, 05:03 PM   #11
Zeta4 is offline Zeta4  United Kingdom
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Yes it does. By my calculation with the 1:26 step up (for maximum gain) and
to provide 100R for the Denon the secondary load impedance needs to be 67K.
This includes the grid leak resistor. So to provide the correct load for the Denon
the grid leak needs to be increased to say 68K with no other load resistor.

47K on its own provides a load of 69R for the Denon which may be near enough.
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Old 3rd February 2013, 05:07 PM   #12
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Let's start again, you have a cart Denon DL103

Output voltage 0,3mV
Load impedance > 100 ohms
output impedance 40 ohms

Ideally you need a MC step-up 1:10 = gain 20 dB

Your step-up minimum position is 1:18 = gain 25,11 dB and your cart sees a load impedance of 145,1 ohms that is OK for you cart > 100 ohms, if you want increase or decrease the load impedance seen for your cart you must use the last calculator (resistor tuning) to accomodate the load impedance that you want.

I hope now this help.
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Old 3rd February 2013, 06:21 PM   #13
rongon is offline rongon  United States
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Thanks so much y'all. I guess I can use the 300R primary and take it from there. I appreciate your patience with me.
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Old 3rd February 2013, 08:22 PM   #14
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It's a good point to start, good luck.
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Old 3rd February 2013, 09:31 PM   #15
martyh is offline martyh  United States
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Not to throw a wrench in the works or to be a butinski but I like the 103 loaded down. 60 Ohms is best to my ears and I have tried with multiple transformers. Might be a system thing, I use the cart on a SME series two with a modified (gain reduced) ARC PH3. Donít be afraid to try it down to the source impedance of the cart.
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Old 3rd February 2013, 10:05 PM   #16
rongon is offline rongon  United States
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Quote:
Originally Posted by martyh View Post
Not to throw a wrench in the works or to be a butinski but I like the 103 loaded down. 60 Ohms is best to my ears and I have tried with multiple transformers. Might be a system thing, I use the cart on a SME series two with a modified (gain reduced) ARC PH3. Donít be afraid to try it down to the source impedance of the cart.
It's funny you should mention that. I like my DL110 loaded with 1000R, even though Denon recommends a 47k load. The difference is night and day better loaded with 1000R. I'm going to try the DL103 into each of the three primaries of the TKS-27 (150R, 200R and 300R), with the secondary working into the standard 47k load. I guess we'll see which one I like best.

Once again, thanks to all for the answers.

--
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Old 26th June 2013, 07:13 AM   #17
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Hello,

I have 1:10 Tamura transformer (small cylinder like those that used for the studio equipment, model datasheet is unknown). As seller said, primary is 150 Ohms impedance, secondary is 47K impedance. DC tester shows 20 Ohms on primary and 780 Ohms on secondary.

Using the calculator from the link above, I see that DL-103 is getting 470 Ohms which is too much, and I have to add resistor of 12K to the MM-input (47K) in order to get 100 Ohms. Is this correct?

Last edited by vitalbesson; 26th June 2013 at 07:16 AM.
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Old 26th June 2013, 08:02 AM   #18
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My cart is a DL-103R. SUT is a Cinemag wired for its maximum 30db gain. Phono is 45db gain. In my system that combination offers the best dynamic performance. I've 2 other makes of SUT wired around that figure with similar results. Switching them to lower gain reduce the dynamics a great deal.I've not had opportunity to hear any of 10X gain. I'm remain skeptical of any SUT with only 10X gain or >150ohm input impedance. Its been my assumption could be more suitable for microphones but not MC cartridges for vinyl play in practice. Having said that, personally I insist a SUT with in the region of 30X ratio with 47Kohm secondary output to the next stage at 40-45db gain, nothing less.

Last edited by coolmaster; 26th June 2013 at 08:07 AM.
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Old 26th June 2013, 08:19 AM   #19
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103R require different load than simple 103.
As for the turn ratio etc - for the moment, I have no other options. Only one I've tried - Beyer Dynamic with 1:15 ratio. Tamura performs better, exactly in dynamic, which is kind of opposite to what you are saying. Sonically they are more or less close, but Tamura shows more dynamic. I'm not sure about the correlation between ratio and overall sonic performance, never heard about it.

Some more details to add to the question above. Before MC transformers I used DL-103 with additional tube stage. Cart load was 180 Ohms resistors. After replacement to transformers I see in spectrum of the recorded sound (same record, same fragment pick), that now highs is getting a little up from the 20-22 kHz to 48 kHz, like 1...2 dB higher with transformers, than it was with the tube. In the area of 20 Hz...20 kHz spectrums are identical. Is this behaviour related to less load to the cart? That is probably not that much important, but good to know.
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Old 26th June 2013, 09:33 AM   #20
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I think it boils down to how the thing is constructed, its size, resultant transient and frequency response that make them all sound different even though they may pose the same boost ratio. Bigger transformers offer bigger bass response in practice (of course there's trade offs in some areas). In use and to my ears, if I switch to the higher impedance, the effect is like I've turned down the bass a couple of notches.
In practice its the same with tube output transformers, each are unique in its own quality, and the associated circuitry have to be custom tuned to obtain the flattest frequency response at the output.
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