does MacBook Pro need a DAC?

Not an engineer with a basic question. Just got a new MacBook Pro. It has AudioMIDI setup with format up to 96k hz.
I am using it by plugging in a cable into a headphone jack with the other end going into the receiver. A friend suggested I get a DAC. but I don't see what purpose would an additional DAC serve. Isn't my MacBook Pro already converting digital to analog signal? and is it doing it efficiently? enough for high quality reproduction? thanks in advance to all who respond
Does not require an external DAC, but one can improve sound quality. You may or may not think it’s worth the effort.
I plug my RCA to mini-adaptor into the headphone jack on my MacBook Pro, that's how I watch movies. Then to improve the sound I move one Synergistic ECT and stick it on the laptop. Finally I place one of the amazing eCards on it. These improve both image and sound. It works really well and my standards are fairly high.

Yes you can do even better with a DAC. A DAC that will also sound even better with an aftermarket power cord. And sitting on Cones. On a good Shelf. With a better interconnect. Before you know it you've spent as much as the laptop, which ultimately is what you still have, a movie off a laptop. Which can be quite good, and very cost effective. But only as long as you let it be cost effective.

I use a dac with my macbook. Makes a huge difference, even a cheap DAC makes a big difference.
Well in that vein maybe he should get an isolation platform and black diamond racing cone feet as well as an aftermarket power cord with Bybee purifiers for his MacBook.  Come on the OP just asked a simple question about a DAC
Depending on your "receiver", you may do better with USB, HDMI or even ethernet/wifi from your MacBook Pro to your "receiver"... I have used all three from my MacBook Pro to my Yamaha AVR, which in my opinion, sounds much better than analogue headphone audio out from the MacBook Pro... In my case the Yamaha AVR has a nice Burr Brown DAC built in... I have since upgraded to a Lumen U1 Mini streamer and Chord Qutest DAC for yet another level of audio nirvana...
Does not require an external DAC, but one can improve sound quality. You may or may not think it’s worth the effort.

All true. Just to expand. a) the MacBook pro has a built in DAC =. b) it is mediocre. c) what is your quality standard? In a reasonably resolving audiophile system, even a $99 Schiit Modi will destroy the internal DAC. A real DAC is a revelation.

Caveat #2: This is about very high quality sound. none of this matters without a good --> to very good system. YMMV.

Part of the answer to the OP's question is another question.  What are you listening to using your MacBook Pro as the source?  Music, movies and videos? Another question is whether your receiver and speakers will readily allow you to hear the greater resolution/clarity of a separate external DAC.  

In general, I agree with aka_ca.  You can achieve a significant improvement in sound quality with a modestly priced Audioquest Dragonfly DAC, which plugs into one of your laptop's USB ports. Is it necessary?  No.  But if you listen to music, particularly acoustic music (classical, jazz, acoustic guitar), the improvement in sound quality should be very noticeable. For rock music with lots of electronic amplification, probably less so. For movies, a lot will depend on how much you listen to vs. watch them.  

A number of dealers who sell these external DACs have good return policies, so you can try one and see if the difference in sound is enough to justify your spending the money for it.  
Take a look at a Schiit Modi 3,  excellent performance and inexpensive.  You will hear a difference immediately. 


And other Mac book(Pro)  experts- I am interested in an older model that has the Super Drive (CD/DVD playback). And suggestions?

Happy Listening!
Any outboard DAC will likely be better than the internal one.  I’ve found that a good DAC is key to having the music converted properly. Even with cheap speakers you’ll likely hear a quite noticeable improvement.  When I moved to an outboard DAC on my Mac Mini, a Meridian Director,  I was amazed at the improvement. So much that after a couple weeks I upgraded to the Schiit GUNGNIR Multibit. It was crazy how much better the music was.  Two hours into the GUNGNIR and I knew I couldn’t live with it. I had to have the Yggdrasil. All three upgrades within a six week period.  The DAC is extremely important. It’s where the music starts. 
If money is an issue, you can get Audirvana for $79.00  It is a vast improvement on the built in DAC.  

I have an external DAC in my main system and use a Innuos Roon core, but when I travel I can even hear a huge difference using my MacBook Pro and a bluetooth speaker
I use this for my digital files in an otherwise high quality analog system:

MacBook Pro >  USB (C TO MICRO USB CABLE) > Chord MoJo > Black Dragon (MINI PHONO TO RCA CABLE) > Preamp

This is a reasonably low cost solution providing very good sound for me. Depending on the quality of your receiver, this may provide a substantial increase in SQ. Good luck.

Not using a DAC with a Macbook is like not using a decanter with a fine red wine. f1status above has it right. Your learning curve may not be as steep as his, but every step will be a big one. Start with any of the cheap DACs mentioned above.
Just listen to it for a while first.  Just enjoy your music, movies etc..
Whenever you are ready, borrow a dac from your buddy and just see if you can hear the difference.

My PC's built in chip set failed. Followed by an failed add in sound card a year later. I moved onto external DAC/amp at that time and brought my stack forward onto every new PC build for quite a few years now.
If you watch movies, then it is definitely better to take advantage of your receiver's DAC/surround sound processor.

If you listen to music (and that is the impression I get), give your receiver's DAC a try and keep it that way if you like the sound. If you want even better sound quality, go for a better, standalone DAC.

(Was it Neil Young who recently said that the Macbook Pro has Fisher-Price audio quality?) 
I run a USB Audio to my McIntosh MA8900 and it works fine. Not the best out there for sure (given the limitations of the MacBook) but it is affordable until I get a better solution.
i listen to Tidal. Master tapes are favorites of course. Based on what you all said here, I decided to go with an option I can afford at the moment, Shiit Midi 3. My tastes are eclectic but tend to new classical music. Will post my experience with the DAC, after I get it. 
Badger_erich: Could you, please, post if/when you find a different solution from the one you currently use? I have a Rotel and B&W 805s at the other end. am already quite happy with the sound 
thanks to you all. I really appreciate you taking time to help me.
If money is an issue, you can get Audirvana for $79.00  It is a vast improvement on the built in DAC. 

Either i'm missing something here or need to point out an error.  Audirvana is a media player (software). It is not a hardware digital-to-analog converter.  If you use Audirvana (or itunes or any other player) you still need a DAC to physically create the analog wave-form from the code.  The MBP has a cheap one built in.  You can buy external, better ones from $100 -->> $10,000, with diminishing marginal returns.
Someone also asked about the superdrive.  In general any such removable, optical media, compared to playing the ripped file off the HDD or SSD (better) will generate higher noise at minimum. Whether you find this significant depends on many factors that i wont get into.

Coincedently, this weekend I received a used, Audioquest dragonfly, black that I bought for $50 on eBay.
It was a very noticeable improvement over my 2016 MacBook Pro's analog output. The mids and highs were much more clearly defined...making the Mac DAC seem quite muddy and distorted.
It's not as good as using the DAC in my Marantz cd6006, but it's my laptop.
Some MBP laptop's headphone jack (3.5mm) is also an optical output!  Really.
when sending audio out, look straight in to the empty jack... If you see a little red light inside, then it's a digital optical out that can connect to a optical input on a surround receiver or any device with an optical input.

Oh, hell yes...
 you. Definitely need a DAC for Mac Book Pro myself I’m replacing my PS Audio DAC III
with either a Schiit Audio Gungnir or if I can get my hands on Denafrips Ares II DAC
both are R2R DACs.
As many have stated a DAC will make for a significant improvement. Evan a simple USB driven one such as the Audioquest Dragon fly models or even a Schiit Modi 2. 
If you want to use the Mac port as a toslink connection, you will need to buy a miniplug extender for your toslink cable or buy a new toslink to miniplug cable.

if you want anything more than background music, you will need to use an external dac. As with most components, the better dacs will cost more.
quick comment: there is talk here of the headphone jack being optical as well. Maybe, maybe not, either way don;t use it. Toslink is merely the optical version of SPDIF. It has some disadvantages - limited to 96 kHz, and very jittery. Since you have USB, use that instead. Toslink is the last choice for great sound.
many thanks to everyone who responded to my original question.
following consensus advice, i got a DAC, cheap one, Shiit Modi 3.
And you were RIGHT as far as I can tell. Detail, detail, detail -- much more of it.
Modi 3!
What an excellent bang for the buck product.
Maybe one of the best buys currently out there.

Is there an equivalent to the Dragonfly - compact quality converter - but for audio in (microphone)?