How old is too old for a Dac?

Its all down to listening at the end of day.

I bought an Audiolab M Dac plus a few weeks back . I really like it.

Spoogemonkey,

To follow up, I suggest you set a budget for your DAC, and then choose two or three used components currently selling at that price, plus two or three current/new DACs at the same price.  For example, if your budget is $500, then look for used DACs currently selling around $500 regardless of their original retail price.  Audition and compare them in your system with new DACs selling for up to $500.

For new components you need to work with local dealers who will let you borrow demos.  Use forums and trusted reviews to narrow down your choices.

For used, as long as you don't over-pay and don't keep too long, you should be able to purchase and re-sell without losing any/much money.  For used, again I suggest to keep it to not more than five years old. 

As for Bryston, Ressonessence or any other brand, new or used really depends on your budget.  I mentioned specific brands because I and/or others I trust, have generally positive experiences with. If new ones fit within your budget, consider them. If only the used ones fit, then consider those instead.  Oppo as others here have mentioned also do well at their price point.  

I set a budget and look for a DAC that is used, however 3-5 years old. I believe I can purchase a better built DAC that way. Better power supply and analog output stage being a priority. I am a fan of external USB/SPDIF conversion so USB implementation is not an issue.

I have put to use a couple older DACs purchased in the last week:

A Audio Alchemy DAC-in-the-Box (~1994 model, $75) which I am using in the living room low budget system to augment audio from inexpensive BR players for Video. Works fine considering its age and am sure it helped smooth the sonics coming from many of the early model DACs sold in the 80s.

A Bel Canto DAC2 ( ~2004 model, $275) which I compared to a Schiit Bifrost Uber (2013 model, $225) in my second system consisting of a NAD236BEE driving B&W 685s via Audioquest cables. The Schiit won out for me in that system, having a less analytical sound probably due to greater 'digital bloom' from the DAC2 on some aggressive rock CDs. I did like the DAC2 when driving my Schiit Vahalla tube headphone amp. Seems to make for a more lively presentation. However, in truth I haven't spent enough time to fully appreciate the differences between these DACs.

 

I do 90% of listening via itunes/Apple music, I recently bid on a Redgum (Australia) DAC, i read great reviews, it was designed to be a DAC for a CD transport and was about $2k back then, its from the early 2000’s. I did not expect to win but i did, total delivered was $300, so i figured id try it in comparison to my exdisting iFI iDAC nano USB. The Redgum DAC only has SPDF in so i needed a USB to SPDF converted, i got a cheapo on amazon for $30.

I spent some time A/B’ing at home and i was shocked at how superior this old technologically inferior DAC sounded compared to the iFi ($200 new), hardly apples to apples but the iFI is capable of far higher resolution where the Redgum caps out at Redbook (44.1/16 bit). In my research i found that the Redgum has 5 power supplies and its own internal re-clock, where as the iFI is powered by USB and has a built in volume control (meant for portable listening). While the iFI souded great and WAY better than my Macbook internal DAC, the Redgum blew it away. Even at 100% volume on the iFI the Redgum seems twice as loud but where it really shined was the separation of instruments in the mid-hi frequency range, the outlines of each instrument or voice was more well defined, the music just sounded more lifelike.

At some point when the big audio streaming services bump up their specs and catalog i may need to upgrade but at this point i am very please with the old DAC nobody wanted anymore.

If it was high quality in its day, you dont need higher than Redbook resolution and will only cost you a few hundred bucks, you may as well take a chance. you may be pleasantly surprised.

Rig:
Apple Music/iTunes
--> Signstek Audio USB to SPDF converter
--> Redgum RG5 ENR DAC
--> Rotel 985BX integrated
--> B&W CM9 S2

there is a fair amount of recent research into noise injection

I am not clear on whether the engineers think that an optical of WiFi connection solves those problems or not

I'd bet you could find a new DAC that sounds better than one from ~~8 years ago even on redbook... the problem is to find one