Line out from a portable unit

[sfbp 8]

If I set a minidisc or other portable to LINE OUT, what other problems can i expect feeding that into a common-or-garden sound jack on a mixer or other pro sound equipment? I have a cable with 3.5mm on one end and 6mm on the other (1/4"). Both are stereo jacks but the receiving end is defiantly mono. No idea how to fix that.

What I do know is that with some combination of adapters that the sound was very iffy and dependent on twiddling the jacks. However even with my nice new direct cable with gold contacts on each end there are still some problems with limiting (and the sink device supposedly has tons of headroom) as i increase the volume beyond about half way round the dial.

For the record, for this test I used an NW-HD5, battery fully charged. Sounds fine into headphones.

[kgallen 5]

Either:

• 3.5mm TRS (MD end) to 2x 6.25mm TS jack plug (mixer end)

Or if your mixer has them:

• Phono (RCA) inputs using a 3.5mm TRS to 2xRCA plug

The mixer probably has "balanced" jack inputs which use TRS. Using a "mono" TS jack plug makes the input "unbalanced".

The historical reason for TRS jacks was for balanced connections (Hot,Cold,Shield) versus TS jacks for unbalanced (Hot,Gnd) connections. The TRS format got "stolen" for stereo (unbalanced) connections. The TS "unbalanced" jack can be plugged into a TRS "balanced" input socket. Since the ring is the Cold connection, Cold gets shorted to Shield which results in an unbalanced connection.

If your portable is battery powered or using a Sony Class2 (no earth) PSU then there is no chance of a (mains) earth loop between MD and mixer.

After that you're into a "Direct Inject" (DI) box but you don't want to go there for this setup.

The "weird sound" is due to phase cancellation - I bet you lose most of the "centre field" of the stereo image, which is usually the vocals.

Post a front-on picture of your mixer then I can advise more directly.

[sfbp 8]

It's barely a mixer.

The absolute simplest thing that supports a "real" microhone and headphones and works with USB hopefully without any latency

I'm new at this "pro" stuff, all these galumphing great jacks I don't really want.....

The simple aim of this device (for me) is to input a sound stream from a music device, and mix that with speaking on a a microphone (plugs in on the left).

The rest ought to be do-able in software but this part seems easiest without.

[kgallen 5]

Is there anything on the back or is the input that 6.35mm jack on the front?

If it can support a "real" microphone then make sure that 48V phantom power is never turned on otherwise poof will go your MD... (probably phantom power is only on the XLR though, you should be safe with TRS jacks...)

I'll try and dig out some kind of manual so I can qualify my rash statements!

[BearBoy 11]

If it’s anything like the 8i6 then phantom power will only be on the XLR input. Best to check the manual though. 

[BearBoy 11]

Does it have SPDIF connections on the rear?

[kgallen 5]

Yea ok so that jack on the front is TRS balanced and there is only one channel on that box so if your MD material has any stereo material then you're going to need to merge them, which will take a couple of resistors and a bit of faffing about.

Otherwise you will need that 3.5mm TRS jack (MD end) to 2x 6.35mm TS jacks and just plug one of them into the Scarlett and you'll have to pick the left or right channel to work with...

[kgallen 5]

1 minute ago, BearBoy said:

Does it have SPDIF connections on the rear?

USB2.0 and line left and right according to the manual, so no.

[kgallen 5]

Regarding the mic, what have you got? You will be safe with the phantom if you have a balanced XLR cable (2 cores plus screen) and either a dynamic mic (like a Shure SM58) or a condenser mic (line a Sennheiser E614). For a dynamic mic (basically a loudspeaker in reverse), phantom=off, for a condenser, phantom=on.

 

(Not suggesting you have either of these mics, just pointing at something you can find a picture of).

[BearBoy 11]

Did you have the "INST" switch engaged when you were trying to record from your MD player? You possibly don't want that engaged as it is designed for recording something like an electric guitar straight into the interface.

[kgallen 5]

( @BearBoy - I think we've blown it. Stephen's gone to lay down in a darkened room...)

[BearBoy 11]

[sfbp 8]

Stephen was taking SO to post office to mail an unmailable parcel. Still unmailable as the address for mailing got left behind.

The mic is absolutely fine, its a Shure SM58. Thanks, I had already been warned about 48V. That thing is built like a tank though. What I am curious (RTFM) what the "Air" button does. Both inputs seem to work regardless of whether their associated button is pushed.

If none of this works, it renews my determination to revive the very old MOTU that I have that has ALL the things you mention. However I don't think my portable will give me SPDIF out so there's another whole layer of complexity feeding something that does Coax out. Incidentally the MOTU SPDIF connector is a 5-pin DIN (ugh). Nah, there's Coax too.

Blast, the postie says he was forbidden to bring the new (used) Mac and it's sitting at the Sub PO and won't be available till tomorrow. The MOTU absolutely refused to work with a Firewire 400 sound card in a PC, sigh, but I know it works fine with a VERY OLD Mac. Hence the excursion into Focusrite territory. Also curious because the Focusrite is the only thing that I can find that gets low latency because they have their own ASIO driver. So if I end on PC then I have to investigate sofware mixers, and on Mac maybe the Motu stuff will do what I need.

[BearBoy 11]

Re Air mode:

Activate the Air circuit on Scarlett 3^rd Gen’s upgraded mic preamps to make your guitars and vocals sound instantly brighter and more spacious, giving them a lustrous sheen that can make all the difference in the mix. Air emulates the technology of the same name from our legendary ISA preamp – just ask your local hit record producer how big a deal that is.
 

https://focusrite.com/en/news/introducing-scarlett-3rd-gen

 

 

[kgallen 5]

4 minutes ago, sfbp said:

What I am curious (RTFM) what the "Air" button does.

They've just got some shaping filters in there to make it sound a bit like one of their fancy mic preamps.

Think "UK Tuned" labels on Sony Minidisc players. Just a tweak to the frequency response characterictics of the post-DAC low pass filter.

[sfbp 8]

So it's really hot, then. Hot air, in fact.

It will likely NOT be convenient to find a Coax output, however I do have a converted TOSlink<->Coax and I just ordered another $10 wonder that extracts SPDIF Opt and Coax from an HDMI source (wonders will never cease!).

[kgallen 5]

I'm lost (or I missed part of the conversation!). What are you going to do with the SPDIF? There is no SPDIF on the Scarlett, so are you going to feed it direct to your Mac/Belkin?

[kgallen 5]

6 minutes ago, sfbp said:

So it's really hot, then. Hot air, in fact.

Indeed! :-D

[sfbp 8]

spdif would be another way to get sound in, 'tis all

[sfbp 8]

4 hours ago, kgallen said:

Yea ok so that jack on the front is TRS balanced and there is only one channel on that box so if your MD material has any stereo material then you're going to need to merge them, which will take a couple of resistors and a bit of faffing about.

Otherwise you will need that 3.5mm TRS jack (MD end) to 2x 6.35mm TS jacks and just plug one of them into the Scarlett and you'll have to pick the left or right channel to work with...

I cheated. I pulled the jack half way out. Works perfick, to quote Pop Larkin.

Nite all