Dave, thanks for all your effort , ive got one more idea as well that I'm going to try , let you know my , findings, have battery powered cd transport in RCA dac to preamp in RCA with the super modded audio horizon dac ,sound ,harmonic textures ,detail , weighting bottom,noise floor ,goose bumps everywhere Thanks guys for everyones thoughts suggestions your the best regards pavpet
How to get balanced inputs working
I have mbl 5011 preamp with a pair of balanced inputs ,when I run dac through it with switch on dac to xlr,which I know is fully balanced , I receive no audio, when I put switch on dac to rca I get. Music don't tell me mbl 5011 has a bogus balance input that's really unbalanced
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Al .. Reverse polarity makes perfect sense and what I first thought of if you flipped Hot and Cold PIN .. but not being very well versed in Balance Technology I knew you would know and respond .. I seem to remember some Agon members having a problem with this interface many years ago .. thats what made me think it could be Pavpet's problem Pavpet .. if my last post was a Long Shot .. this one is a Shot in the Dark I quickly read a review on your Pre at Dagogo ... from the article it says there are multiple volume controls to control different groups of outputs ... Dagogo Review Heres the blurb from Dagoo Of particular interest are the separate volume controls. The preamp has its own main volume control (it is a very high-quality analog potentiometer) which controls both of the separate output groups. Each output group has three separate outputs: one group with two XLR connections and one RCA connection, and a second group with two RCA connections and one XLR connection. Two separate, additional auxiliary volume controls allow you to control the relative output of each group, which gives you incredible flexibility." I know you know your Pre inside out ..so this is just speculation based on what I quickly read .. Dagogo says .. Two separate, additional auxiliary volume controls allow you to control the relative output of each group, which gives you incredible flexibility. Is there a chance you have the RCA and the XLR ICs plugged into different groups and possibly have the volume control on the RCA group turned up and the secondary volume control turned down that controls the group the XLRs are plugged into ? If both the RCA and XLR ICs are plugged into the same group ... that shoots that theory to Hell .. but if they are in different groups ... turn all the volume controls up if they are not ... or move the XLR to the same output group that the RCAs are plugged into and playing through if it isnt Just a Shot in the Dark "Big problems have small solution" . |
The performance of a digital cable, balanced or unbalanced, will often be significantly dependent on the relation between its length and various unspecified variables, including the risetimes and falltimes of the digital output signal of the CDP or transport, among others. More often than not, it would be desirable to avoid intermediate lengths such as 1 meter, and choose a length of about 1.5 meters (approximately 5 feet) or slightly longer, or, if practicable, a very short length (e.g., 8 or 10 inches or less). See this paper. Good luck! -- Al |
The audio horizon dac 3 has an input selector that is used to select between either 1) RCA INPUT or 2) XLR INPUT. This selector does not have anything to do with the output selection. From your above post, the dac is connected to the transport using a RCA connection; therefore, the dac's INPUT selector must be set to RCA for any signal to be outputted in either RCA or XLR output. Do you get any sound when your dac is switched to RCA INPUT mode? It is not clear that you have tried this. |
Thanks, Dave. An inconsistency or reversal of pins 2 and 3 in the connections between the DAC and the preamp would only result in an inversion of absolute phase, though, which would at most have subtle sonic consequences on some recordings, and no consequences on many others. It would not cause the audio to be absent. It is conceivable to me, though, that differences between the two preamps in how the grounding of pin 1 is handled could contribute to the (quoting from one of my earlier posts) "small differences in grounding conditions that may occur depending on which preamp is connected" that I speculated might "mean the difference between the DAC working and not working" when its input select switch is wrongly set to the XLR position. That speculation is also, of course, a long shot, but regardless of what is going on it would seem clear that the switch on the DAC should not be set to select an input other than the one that is connected, whether it happens to work that way or not. Best regards, -- Al |
Long Shot here ... dont certain/some European and Japanese Mfgers use a different PIN OUT assignment/configuration than the Standard XLR PIN OUT configuration that is used in the majority of the XLR configuration connections In a standard pin assignment ... Pin 1 is ground .. Pin 2 is positive and Pin 3 is negative Is it possible that Pavet's MBL pre may be using a different Pin assignment and not lining up with the Auto Horizons PIN 1 2 3 standard configuration .. From Wiki ... Prior to the introduction of this standard, the wiring of pins 2 and 3 varied. The pin 2 "hot" and pin 3 "cold" convention was typically used by European and Japanese equipment manufacturers, but American companies used pin 3 "hot" and pin 2 "cold". This caused problems when interconnecting equipment with unbalanced connections. The pin 3 "hot" convention is now obsolete but is still found on vintage equipment.[15] Pin 1 has always been ground and/or shield if the cable is shielded, and many connectors connect it internally to the connector shell or case Like I said .. LONG SHOT ... maybe you can check with MBL on their PIN assignment/configuration for their XLR connection on that model preamp and see if it aligns with the PIN out on the Auto Horizon Dac . |
03-25-13: PavpetI realize that is what you are saying. You are saying that when you apply a digital input signal to the RCA digital input of the DAC, and set the DAC so that its unconnected XLR digital input is selected, you get audio when the Sugden preamp is connected to the DAC's analog output via XLR, but not when the MBL preamp is connected to the DAC's analog output via XLR. My comments in response to that are in my preceding post. Regards, -- Al |
If you are saying that with the Sugden preamp everything worked well when the digital input to the DAC was provided on its RCA input connector, while the input select switch on the DAC was set to select its XLR input connector, that makes little sense. If that is really what was happening, the only explanations I can think of are that either the input select function of the DAC is malfunctioning, or its design is such that there is some amount of "crosstalk" (unwanted coupling) between its two digital inputs. In either case the condition would presumably be very marginal, such that small differences in grounding conditions that may occur depending on which preamp is connected would mean the difference between the DAC working and not working. That all seems very farfetched, but those are the only explanations that occur to me if the facts you have reported are accurate. In any event, if you are inputting to the RCA digital input on the DAC, its XLR/RCA input select switch should be set to RCA. Regards, -- Al |
Its a shame That I'm having a problem with the mbl balanced , because that's where the audio horizon shines more low level detail ,better tmber in voices ,larger soundstage , overall better musicality ,as the original hook up was with the sugden preamp in xlr and was awesome and the sugden is no mbl so I assume all these nice harmonic textures were from the dac |
It appears, as is typically the case, that the XLR/RCA switch on the Audio Horizons 3-series DACs selects between the XLR and RCA digital INPUT connectors, and has nothing to do with which analog output connector is being used. The XLR and RCA analog output connectors are presumably driven simultaneously, as Brf indicated. So the reason that you hear nothing when "XLR" is selected is that nothing is connected to the XLR digital input connector. The MBL preamp has nothing to do with the issue. The bottom line: Hey, no problem! Regards, -- Al |
What is the model number of the Audio Horizons DAC? And am I correct in understanding that the switch you have been referring to as the "switch on DAC" and as the "DAC switch" is located on the DAC, not on the preamp? Or are you referring to a switch on the preamp, which acts on the input of the preamp that is connected to the DAC? Regards, -- Al |
You might try to "reset" the 5011 back to factory settings. 8.1 Resetting to factory settings Follow the steps below to reset your preamp to the factory settings: 1. Switch the preamp off. 2. Press and keep pressed the fourth button on the right side of the display. 3. Holding the button pressed, switch the preamp on. The display will remain dark. 4. Release the button. 5. Switch the preamp off. 6. Wait five seconds. 7. Switch the preamp on. Factory settings: Out1 and out2 on, CD1, maximal display brightness |
Yes the audio horizon dac was working in balanced no problem ,can't get the mbl 5011 to work , in xlr , when dac switch on xlr with mbl hooked to balance no sound , as soon as I switch ,from xlr to RCA while still hooked to balance inputs ,music plays , I therefore assume mbl not true balanced input, or it has to be activated by mbl dac |