Best way to get audio from iMac to Amplifier

Vazzyb

macrumors member
Original poster
Mar 18, 2009
99
0
Cambridge, UK.
Hi

I wanted to know what the best way to get audio from my 2011 iMac to an external integrated amplifier was. The amplifier has both digital (optical) and analogue (phono) inputs; its a Rotel RA 1520.

My primary concern was that I wanted to keep the quality of the sound as high as possible. The rest of the system was designed with quality in mind. Therefore using a stereo jack to phono adapter is probably not a good idea.

Are there digital alternatives? eg. using an external sound card with an optical output?

Its not just music that I want to send to amp, its also the sound from movies. For music, I think I could use a Sonos.

Thanks very much

Vb
 

thebignewt

macrumors regular
Jun 10, 2011
119
0
I don't think there's an easy wired connection. I use an Airport Express and a simple RCA wire to connect it to my receiver for my home stereo (pretty good Klipsch speakers). The only ouput connections for that unit is 3.5mm headphone jack, and a USB for a printer). That only plays iTunes music library, I control that with my iPod touch and the free Remote app. I also bought an Apple TV (they are both about $100). I connect that using an optical audio wire to my surround sound amp that's with my HDTV and speakers (Paradigms). It also has an HDMI output. That will also play my iTunes music library (as well as video). An apple remote comes with that unit and the menus are on the TV of course. I you are bent on optical wire then you'll have to use your TV to make selections. I suspect both ways will sound good, at least they do for me.
 
Last edited:
Comment

aliensporebomb

macrumors 68000
Jun 19, 2005
1,844
223
Minneapolis, MN, USA, Urth
Why not

Why not use an optical cable from the audio out to the SPDIF in on the Rotel? It's a mini SPDIF cable on the iMac end and depending on what your Rotel has you might go mini or full side SPDIF. I've been using the digital inputs on my iMac from a digital audio mixer (full size SPDIF out) and it works well. They are digital in/outs on the iMac machines.

Interesting that you have a Rotel amplifier - I do too but it's about twenty years old and still works great. No digital I/O there so not quite sure what I would use.
 
Comment

88 King

macrumors 6502
Jun 18, 2011
377
0
London, UK
The imac have optical out through the headphone jack.

The cheapest solution is to get 3.5mm headphone jack to optical converter.

If you want to spend money on external sound card, I think it’s better to get a digital audio converter (DAC). I’m using DacMagic by Cambridge Audio, it produces very good sound for reasonable price.
 
Comment

zarathu

macrumors 6502
May 14, 2003
274
46
I'd use the headphone jack into the tape or the cd input. I don't know what other choice you have. Of course if all you are transferring is mp3's it may not make that big a difference. Sampling rate on mp3's is not that super.

What kind of audio are you transferring out.
 
Comment

MaloCS

macrumors regular
Aug 11, 2011
240
394
I just did what you are trying to accomplish.

You'll need the following:
  1. Belkin Toslink cable with 3.5mm adapter Link to Belkin Cable >>
  2. A stereo/tuner/receiver with optical input or...
  3. An external DAC (Digital Audio Converter) with optical input and RCA outputs. Link to External DAC >>

The first thing you'll want to do is set the audio output jack on the rear of the iMac to digital output via the audio preferences.

Then you connect the 3.5mm adapter to one end of the Belkin cable and insert it into the audio output jack on the rear of the iMac.

Finally, you plug the other end of the Belkin cable into an optical input in either your receiver or external DAC. If you choose to use an external DAC you will need a set of RCA stereo cables to get the audio signal from the DAC to the receiver. It looks like your receiver has an optical input so you do not need an external DAC. The only reason to use an external DAC in your situation would be to bypass your receiver's on board DAC if you were unhappy with it. In my particular case I'm using a receiver from the early 1970s so an external DAC is a necessity.

One thing to take note of is that once the audio output is set to digital the iMac locks the volume to 100% and prevents the user from adjusting it. I'm assuming that Apple locked the volume to 100% because the receiver will now control the volume.

Keep in mind that you may find similar/comparable products online for much less money. The links I provided are just to give you an idea of what type of equipment you need to in order to obtain the best quality sound out of your stock iMac. Of course, you can always choose to install a professional grade external sound card but I don't feel that's necessary for audiophile stereo playback.

Some people claim that internal computer noise can seep into the on board audio circuitry and degrade the signal but in several years of using my computer as an audiophile listening source I haven't noticed it. Your ears may be more sensitive then mine but I would give the above setup a try before dropping the coin on an expensive external audio card.
 
Last edited:
Comment

aliensporebomb

macrumors 68000
Jun 19, 2005
1,844
223
Minneapolis, MN, USA, Urth
Fwiw

For what it's worth I've professionally produced at least a dozen commercially released compact discs using Macintosh internal audio circuitry.

Nobody has ever complained about the audio not sounding "clean" enough that I've been aware of.

Most folks are stupefied it was recorded on a Mac in a small studio/office.
 
Comment

Alinoe

macrumors newbie
Aug 25, 2011
19
1
Your iMac has an optical out port. If your amp has an optical in port, why bother with a DAC (unless you're a serious audiophile)? Just get a cable.
 
  • Like
Reactions: chabig
Comment

Fishrrman

macrumors Core
Feb 20, 2009
19,014
6,483
"I wanted to know what the best way to get audio from my 2011 iMac to an external integrated amplifier was. The amplifier has both digital (optical) and analogue (phono) inputs; its a Rotel RA 1520."

I went to the Rotel page and looked at the manual (which has a diagram of the back), and I didn't see any "optical input". Are you _sure_ it has a digital input?

Do you know what kind of input connector is on the amplifier?
Do you know what _type_ of digital input format the amplifier can support?

IF the input is digital/optical, you should be able to use a simple TOSLINK digital/optical cable to make the connection.

You MAY need small "adapters" on either end of the cable. Most TOSLINK cables come with a "rectangular" type of plug that looks like this:
http://www.parts-express.com/pe/showdetl.cfm?Partnumber=180-950&FTR=180-950

You can get a small adapter for the iMac end that looks like this:
http://www.parts-express.com/pe/showdetl.cfm?Partnumber=180-968&FTR=180-968

Here's the same kind of adapter with an "L-shaped" end that swivels (very handy):
http://www.parts-express.com/pe/showdetl.cfm?Partnumber=180-958&FTR=180-958

Here's an "extension coupler" that lets you hook 2 cables together end-to-end:
http://www.parts-express.com/pe/showdetl.cfm?Partnumber=180-966&FTR=180-966

Whether you will need the same adapter on the "amplifier end" depends on what kind of connection port it has.

IMPORTANT: if the amplifier has a "phono type" SPDIF input (looks like an "RCA" phono plug), you may need some kind of "converter" to go between them. The converter doesn't change the signal from digital to analog, but instead "converts the format" between connectors.

There is a length limitation, however. The following info is snipped from widipedia:
"TOSLINK cables are usually limited to 5 meters in length, with a technical maximum[1] of 10 meters, for reliable transmission without the use of a signal booster. However, it is very common for interfaces on newer consumer electronics (satellite receivers and PCs with optical outputs) to easily run over 30 meters on even low-cost ($0.75/m) TOSLINK cables. TOSLINK transmitters operate at a nominal optical wavelength of 650nm(~461.2 THz)."


Again, after a quick review of the manual for the above amplifier, I didn't see any "digital input".

If that's the case, you could still get music out of the iMac and into the amplifier by using a USB/DAC converter box. There are many of them available:
http://www.amazon.com/s/ref=nb_sb_noss?url=search-alias=aps&field-keywords=usb+dac&x=0&y=0
 
Comment

911scanner

macrumors member
Jan 31, 2011
48
0
I too was having this issue when I first purchased my iMac 11,3. I wanted to use my truly digital integrated amp (that I already owned) with some decent bookshelf speakers.

In my quest, I used a digital out cable from the headphone jack for awhile. I liked this method, except for needing better speakers and the lack of volume control integrated into the Mac.

Then I started considering amplified bookshelf speakers. I stumbled on the AudioPro LV2 speakers and have been happy as a clam ever since.

Not an inexpensive option, but you will be amazed when you hear them.


MM
 
Comment

Dtilac

macrumors newbie
Aug 7, 2019
1
0
I just did what you are trying to accomplish.

You'll need the following:
  1. Belkin Toslink cable with 3.5mm adapter Link to Belkin Cable >>
  2. A stereo/tuner/receiver with optical input or...
  3. An external DAC (Digital Audio Converter) with optical input and RCA outputs. Link to External DAC >>

The first thing you'll want to do is set the audio output jack on the rear of the iMac to digital output via the audio preferences.

Then you connect the 3.5mm adapter to one end of the Belkin cable and insert it into the audio output jack on the rear of the iMac.

Finally, you plug the other end of the Belkin cable into an optical input in either your receiver or external DAC. If you choose to use an external DAC you will need a set of RCA stereo cables to get the audio signal from the DAC to the receiver. It looks like your receiver has an optical input so you do not need an external DAC. The only reason to use an external DAC in your situation would be to bypass your receiver's on board DAC if you were unhappy with it. In my particular case I'm using a receiver from the early 1970s so an external DAC is a necessity.

One thing to take note of is that once the audio output is set to digital the iMac locks the volume to 100% and prevents the user from adjusting it. I'm assuming that Apple locked the volume to 100% because the receiver will now control the volume.

Keep in mind that you may find similar/comparable products online for much less money. The links I provided are just to give you an idea of what type of equipment you need to in order to obtain the best quality sound out of your stock iMac. Of course, you can always choose to install a professional grade external sound card but I don't feel that's necessary for audiophile stereo playback.

Some people claim that internal computer noise can seep into the on board audio circuitry and degrade the signal but in several years of using my computer as an audiophile listening source I haven't noticed it. Your ears may be more sensitive then mine but I would give the above setup a try before dropping the coin on an expensive external audio card.
Hello,

Do you know a solution for Macbook Pro please?

Thanks a lot
[doublepost=1565212457][/doublepost]Hello,

Do you know a solution for Macbook Pro please ?

Tanks a lot
 
Last edited by a moderator:
Comment

mikehalloran

macrumors 68000
Oct 14, 2018
1,711
434
The Sillie Con Valley
The 3.5mm to optical adapter is under $3 if you shop around — this is a lot more.
https://www.amazon.com/Recoton-Fiber-Optic-Toslink-Adapter/dp/B0002MQGRM
Only use it if the amp/controller has an optical in. Otherwise, use a 3.5mm stereo out analog. If you don’t feel good paying under $25, Monster makes one.

RCA phono or 1’4” phone inputs, get the right cable. No other adapter is necessary. Phone refers to old phone company switchboards, BTW.

I mastered many CDs on my 2010 with the same setup as a 2011. I use a very high end studio monitor with a 3.5mm to 1/4” male R/L to my current monitor controller, Being passive, it doesn’t have optical in. The cable cost me $15 or so since I had it custom made at Markertek—I wanted the cables a custom length, otherwise I would have bought off the shelf.

My old controller had an optical in. Optical has latency that cannot be avoided—if output only, not an issue. anyway, my new controller sounds better (for the money I paid, it should!). It could be that the DAC in the old controller was inferior but there were other issues so it’s hard to nail it down to any one issue.

Since I went analog instead of optical with my new controller, transferring it to my iMac Pro couldn’t have been easier. Unplug from my 2010, plug into my iMP. Since 2017, Macs do not have optical outs.
[doublepost=1565237770][/doublepost]
and the lack of volume control integrated into the Ma
Yea, that. That’s why I recommend a monitor controller. I can reach out and turn a knob without futzing with internal controls. 3 pages from $49 to $4,000
https://www.sweetwater.com/c417--Studio_Monitor_Management
[doublepost=1565237890][/doublepost]
Do you know a solution for Macbook Pro please ?
What year and model? It makes a big difference.
 
Last edited:
Comment

cynics

macrumors G4
Jan 8, 2012
11,547
1,863
If you are going to go the route of optical from Airport Express I would recommend using a mini toslink to toslink cable over an adaptor + toslink cable. Get as short of cable as you can comfortable use.

This is only my personal experience but I would get some type of modal distortion using an adaptor I had.

Apple may have fixed this by now but the pause between iTunes songs and sample rate adjustments would cause some receivers to jitter since the DAC wasn't prepared for that. Swapping a Sony receiver with a Yamaha receiver from another room fixed that for me. Back then a DAC would need to have very good jitter attenuation to account for how Apple was handling the signal. The problem was that jitter attenuation wasn't the focus for many DAC manufacturers. So a cheap DAC or one in a cheap receiver might work fine while a 1000+ dollar DAC would jitter all the time.

Once I got my setup perfect I was completely unsurprised to find no discernible difference between analog and digital audio quality when output from an Airport Express. Personally I think only the most obnoxious of audiophiles should worry about it the AE and toslink.
 
Comment
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.