drop in
The DIR9001 modules are drop in for the 8416 module except for what I have said about the source selection not working right and also that my upsampling modules don't make any sound with the DIR9001 in front of them.
assume if source selection is not needed and upsampling modules is void, will dir9001 works?
Ryssen
is your configuration like this
dir9001 - upsampling module - scr (receiver) ?
Ebay
The JT-11- EMCF for $50 each on ebay right now are a great deal if you can get them to ship internationally. I have purchased from them twice and they were shipped out the same day.
Same board
It is all the same big Dac Board. You can interchange any of the modules on the same board which is one of the fascinating aspects of the design. I admire the way such different circuits were packaged into modules that all use the same pin connections to the main board.
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It is all the same big Dac Board. You can interchange any of the modules on the same board which is one of the fascinating aspects of the design. I admire the way such different circuits were packaged into modules that all use the same pin connections to the main board.
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Has anyone listened to JT-11- EMCF, DMCF and BMCF? Was there any notable audible difference?
How does LL1690 compare with the Jensens? I use pure silver ribbon as interconnects in all my mods and am slightly concern that Lundahls may sound too bright…. so any input here from people who actually compared the abovementioned transformers is highly appreciated.
Boky
How does LL1690 compare with the Jensens? I use pure silver ribbon as interconnects in all my mods and am slightly concern that Lundahls may sound too bright…. so any input here from people who actually compared the abovementioned transformers is highly appreciated.
Boky
true but base on your explanation i'm worried if the diy dir9001 didn't work...
have you done any mod to the cs8416 chip ?
Legarem prefers the DMs over the 1690s. They are both excellent trafos but have very different construction. The 1690s are much costlier but that in itself doesn't make them better. The BMs are just larger. The DMs have flat response to the limits of my signal generator.
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The BMs are probably overkill at this signal level, but what the hell!
LL1684
Don't forget that LL1690 is an input transformer with higher resistances and possibly higher inductance? (they don't list this on the spec sheet) which may be why some users have found it to sound a little thin. Maybe it is interacting with the interconnect that is following it. It really looks to me that the LL1684 would be the one to try for this application if you want to play with an expensive Lundahl.
Latecomer Questions
Is there a way to search just one thread on the forum? I have actually read most if not all of the thread and I suspect that a lot of my questions are answered, but I just can't re-read the whole thread. Anyway, if one of you transformer experts would be willing to set me straight or point me in the right direction on at least some of this it would be hugely appreciated. Here's what I can't figure out.
Why are so many using 600 ohm/600 ohm transformers? The CS4398 spec says 1K Minimum AC Load Resistance (and max capacitance 100pF). If the secondary is loaded with a higher impedance then the AC input impedance will actually be higher than 600 ohms, but I'm curious why more people haven't used 10K/10K or even a 10K stepdown since 7V P-P seems like a lot of output for a preamp. I noticed that Jensen uses 600/600 in their AS093 app note - has anyone tried that circuit?
How are these hooked up? I saw one schematic showing the primary connected directly to AOUT+/AOUT- with a cap across the primary (HF filtering I presume) and an anti-ringing series cap/resistor combination on the secondary. Is that all there is to it? Does the lack of filtering allow much HF noise to pass downstream into the preamp? Jensen's app note has 249R series resistors plus more filtering. Seems like that might be safer.
Based on the info in the thread, I'm ready to start playing with transformers, but I'd like to get an idea of what the best impedance combination before I start ordering. I'd order several different transformers from Edcor since they're cheap if I could get past their VerySilly terms and conditions checkbox. In particular, the 2.4K primary/600 ohm secondary looks very interesting. Is there an online retail distributor for Edcor?
thanks a bunch,
Jim
Is there a way to search just one thread on the forum? I have actually read most if not all of the thread and I suspect that a lot of my questions are answered, but I just can't re-read the whole thread. Anyway, if one of you transformer experts would be willing to set me straight or point me in the right direction on at least some of this it would be hugely appreciated. Here's what I can't figure out.
Why are so many using 600 ohm/600 ohm transformers? The CS4398 spec says 1K Minimum AC Load Resistance (and max capacitance 100pF). If the secondary is loaded with a higher impedance then the AC input impedance will actually be higher than 600 ohms, but I'm curious why more people haven't used 10K/10K or even a 10K stepdown since 7V P-P seems like a lot of output for a preamp. I noticed that Jensen uses 600/600 in their AS093 app note - has anyone tried that circuit?
How are these hooked up? I saw one schematic showing the primary connected directly to AOUT+/AOUT- with a cap across the primary (HF filtering I presume) and an anti-ringing series cap/resistor combination on the secondary. Is that all there is to it? Does the lack of filtering allow much HF noise to pass downstream into the preamp? Jensen's app note has 249R series resistors plus more filtering. Seems like that might be safer.
Based on the info in the thread, I'm ready to start playing with transformers, but I'd like to get an idea of what the best impedance combination before I start ordering. I'd order several different transformers from Edcor since they're cheap if I could get past their VerySilly terms and conditions checkbox. In particular, the 2.4K primary/600 ohm secondary looks very interesting. Is there an online retail distributor for Edcor?
thanks a bunch,
Jim
look in the top right hand corner of this page there is a button for 'search this thread' so you just have to enter the thread you want to search and hit that. its next to 'thread tools' and 'thread ratings'
Thanks for that - I'm not sure how I missed it. Now that I'm tapped into the motherlode of information, much of what I asked is answered -
- There doesn't seeem to be a consensus on transformer impedance.
- Some folks connected the transformers directly, others have series resistors for a low pass filter.
- and after I sent Edcor an e-mail grouching about their T's and C's they suggested I call and order with a credit card. That's easy enough.
So I'll pick up a couple of transformers and start tinkering.
Jim
Jensen white papers
Read through the white papers at Jensen for an explanation of transformer impedance. Also, you may find the output to be a little low if you go less than 1:1.
Read through the white papers at Jensen for an explanation of transformer impedance. Also, you may find the output to be a little low if you go less than 1:1.