Topic: Just a couple of questions from a beginner

Hi all, I'm set on buying the ADI-2 DAC today and have read the manual and forum in preparation. I'm a little unsure on a couple of points so I thought I'd ask.

Firstly I'm not sure where to source an XLR to RCA cable that has pin 3 disconnected, as per the manual. I saw a thread on here about the same matter but the links to suitable products are now dead. I'm in the UK and I'm having a hard time finding a suitable lead, so if anyone could point me in the right direction I'd appreciate it. I'd like to run the RCA out to a headphone tube amp and run XLR out unbalanced to my speaker amp.

Second is that I'm a bit confused as to what output settings I should use for my speaker amp. I have the option on that amp to change a source's RCA input voltage to 4V, but obviously the ADI-2 has variable output too. What settings would be optimal in this situation?

Third is just a question of how often shipped units are flashed with the latest firmware. I have no access to a PC at the moment so would be unable to update the ADI-2 for a while. The dealer - Juno Records - said that the units were only just received in January so are likely to have the latest revision on them, is this the case?

I think that's it for now, thanks in advance for your help.

Re: Just a couple of questions from a beginner

Hi,

Regarding the XLR to RCA cable you could try designacable.com

The people there make custom cables and connectors. Their website can be tough to navigate, so it is probably best to just tell them what you are looking for and they'll build it for you.

Kind Regards

Rodney Ferguson

3

Re: Just a couple of questions from a beginner

Give Synthax UK a call. Such cables are usually easy to get, but as I am not in the UK I can't help.

You should set your speaker amp to the highest voltage (= lowest sensitivity)  available. The DAC can handle it all. Doing so you minimize noise, hum, mega volume surprises etc.

Regards
Matthias Carstens
RME

Re: Just a couple of questions from a beginner

Thanks Rodney and Matthias, I'll see if I can source some cables from one of the places you suggested. Could you clarify the output settings needed for XLRs running to the speaker amp's RCA inputs, set to 4v as you advise? Am I right in thinking that converting a balanced signal to unbalanced will affect the power my amp receives? If so, what reference level should I choose to maximise the SNR? I'll be using the outputs as fixed.

Just to repeat my query about the firmware a unit received in the UK in January might have - do you update units to the latest firmware before dispatch? There's some great features that have been added since the product's release and it'd be fab if it was up to date out of the box. Thanks again for your help.

5 (edited by Curt962 2019-01-13 23:36:44)

Re: Just a couple of questions from a beginner

JP,

I received my new ADI-2 DAC on 28 Dec here in the US.    It was loaded with Firmware 21.   

There were several FW updates done in Late December which explains how this can be so.  My Unit was simply in-transit. 

FW Updates are remarkably Pain-Free, so you'll have no difficulties!! (Visit the RME Website for the Newest Drivers)

This is a fantastic unit, and Trust you will be Delighted!

Curt

Re: Just a couple of questions from a beginner

Thanks Curt, I placed my order so it should arrive on Tuesday with a bit of luck and a following wind. It's not a big deal which firmware it's running, it's just I'm without a (working) PC at home and installing programs at work is out the question so I guess I'll just have to beg, borrow or steal a laptop from a friend or family member. Either way I'm looking forward to taking delivery, the specs on the unit are top tier and I've never seen one so versatile. I'm glad you're enjoying yours! smile

I found a company to make me a cable (tha ks for the help) so what I actually need to know now is what power the balanced outs produce when wired as advised. Is it the equivalent of 2v so they can be treated like the unbalanced outputs? I'll be setting them as fixed outputs, I need them to be the same volume as the (also fixed) RCA's, but I'm genuinely confused what output setting I need to use.

I think I'm correct that +7dBu with the volume set to 0 is correct for the RCA outputs (I won't be using auto reference levelling) but I'm stumped what dBu setting the XLRs should be set to with the volume at 0, especially if I set my amp to 4v as was recommended. If you could help me out with that I'd really appreciate it, I've Googled my fingers off and I'm still none the wiser. Thanks once again!.

(by the way - you realise that this is what you get when you release professional quality equipment to home users - idiots like me!)

7 (edited by N00b 2019-01-14 11:32:37)

Re: Just a couple of questions from a beginner

Like Matthias said, set your amp to the lowest sensitivity (highest voltage).
Then, on the ADI-2, to keep it simple, you can turn on the Auto Ref function on and set the volume right (starting by the lowest volume).
Your ADI will switch automatically between the different output levels and you won't have to bother. wink

And if you wan't more info between dBu, voltages etc. : http://www.sengpielaudio.com/calculator-db-volt.htm

Re: Just a couple of questions from a beginner

JP,

As an equally new RME User, I simply let "Auto Ref Level" feature worry about the Math.   The User Manual discusses the matter in far greater detail than I can.

Much as you, I'm using my ADI-2 to drive Active Speakers, and Subs.   No headphones involved.    Given that Ambient Noise levels in even a Quiet Room are surprisingly high, that LAST DB of SNR may go un-noticed.   

Let Auto-Ref get you started, I'd Wager you'll be pleased right there. 

All the Best!

Curt

Re: Just a couple of questions from a beginner

Thanks guys, I think from your responses I'm obviously sweating the details too much - the unit is clearly far cleverer than I am so I'll let it do its work (at least until I understand exactly what's going on - I'm determined to get my head around it!). Thanks for the link, N00b, I'll check it out and hopefully the mist will clear.

Using the DAC straight to monitors and a sub? I bet it sounds phenomenal, Curt. I'll be using it primarily for headphones as I couldn't find a DAC/amp that was anywhere near as clean and versatile. However, you're right, with it driving my stereo setup too, extracting every possible dB of SNR isn't that important at all - my amp, speakers and ears are the bottleneck!. I think I got a bit hung up on the numbers. Let's call it over-excitement!.

Thanks again guys, with a bit of luck this'll be the last time you hear from me. But don't count on it smile

10 (edited by Curt962 2019-01-14 18:26:02)

Re: Just a couple of questions from a beginner

JP,

Don't judge yourself too harshly.  You cannot possibly be any more of an RME Beginner, than I.

Tomorrow is the Big Day??  I hope your New DAC arrives on-time.   Enjoy!

Re: Just a couple of questions from a beginner

It's just me, I'm back!. It arrived on time and despite the initial intimidation of that menu system I've got it dialled in perfectly for all my headphones and the external amps too. It arrived with firmware 22, I'm thinking about getting a Windows tablet to update it and run my music from. It's a fantastic unit, the difference between it and my previous gear is clear. It beats my old headphone setup hollow and the DAC feeds my amps better than anything I've tried.

There's one issue that is bugging me and I'm struggling to find a solution. When using 12ohm IEM's I can hear interference. It's quiet but it's there with any source, and it changes depending on where and how I position the power supply. I can sometimes get it so it's silent, but then it comes back. I popped some ferrite core suppressors on and it did help a little (I think, it's difficult to tell), it's running through one of those Tacima strips (although I don't put a lot of stock in it) and despite my best efforts to isolate the wiring I just can't eliminate the interference for good.

What's the best way to have the cable in terms of coiled vs straightened? The lead only needs to run a foot or so from the socket so I've tended to leave the thin wire to the DAC coiled with a suppressor around it. Should I uncoil that? Would shortening the figure of 8 mains wire help? Or coil that up?. It's not a huge deal, but hearing interference between songs or in quiet passages is a bit distracting, especially now I've heard how ghostly quiet it can be when it's all working perfectly, it's really remarkable. I've removed as many other appliances and plugs from around it as possible, there's essentially just the ADI-2 running off that Tacima.

Any hints and tips? Once I can get this sorted it'll be absolutely perfect smile

12

Re: Just a couple of questions from a beginner

You need to check the whole setup.
Is the Phones out set to Lo Power?
What happens if you reverse the power supply plug?
Are we talking about the ADI's power supply?
What is connected to the ADI, and what happens to the interference if you disconnect USB or SPDIF coax or RCA? It goes away. So there is a ground loop between the devices and you need to break it.

Regards
Matthias Carstens
RME

Re: Just a couple of questions from a beginner

The IEM output is set to low power - in fact it can't be set to high power, at least not on this firmware. The power supply plug can't be reversed at the power end in the UK, but I reversed the figure of 8 end and it's no different. Yes I'm using the power supply that came supplied with the unit. I just unplugged everything except the power and the interference is still there (it sounds like faint static). Depending on where I route and place the wires and SMPS I can increase or reduce the static. I've found a spot where it's minimised, but it is still present. It's definitely not a ground loop.

14

Re: Just a couple of questions from a beginner

Ok, DAC IEM does not have low power option.

We had such a case before, electrical ground was missing. You should connect the DAC's ground (ground terminals or housing) to something that is well grounded. Then the interference will be gone.

Regards
Matthias Carstens
RME

Re: Just a couple of questions from a beginner

Old school eh? Okay, I'll give it a try tomorrow, I'll have to dig some speaker cable out, there's copper piping nearby so it'll be easy enough.

Re: Just a couple of questions from a beginner

I'm afraid that didn't work, I had the unit grounded to a copper water pipe and I could still hear interference. The power supply is apparently just picking up RFI/EMI and passing it straight through. I have other supplies I could try - to eliminate the supplied PSU being the cause - but frankly I don't want to plug any others in or risk my warranty. At the moment I have the DAC, cables and SMPS positioned so it's rare and barely noticable so I'll make do with that. Perhaps when I rearrange my room and equipment I'll be able to shield the supply/cables from whatever they're picking up. Cheers for your help anyway.

17

Re: Just a couple of questions from a beginner

That is astonishing. Does the interference change when you touch the unit's housing?

The ADI runs with many standard power supplies as long as they are in the range of 9 to 15 Volts and supply at least 1A. Important is the polarity on the connector, + inner pin. So if you have something that matches simply try it.

Regards
Matthias Carstens
RME