PDA

View Full Version : Running in a DAC



foxysounds
25-03-2009, 16:30
I'm thinking of upgrading my system with an external DAC - probably one of Stan's. However, I'm a little concerned about the long run-in times some people are experiencing.

I don't get to spend nearly as much time listening to my Hi-Fi as I would like so anything that takes a long time to run in (and might actually detract from my enjoyment of my system while doing so) is going to lead to frustration.

One possibility is to buy a second hand, already run-in DAC of course. Is a DAC a safe kind of thing to buy second hand or is there much that can be damaged if they have been misused?

If I buy a new one and run it in myself, am I right in assuming that in order to ensure that all of the components are equally run-in I would need to have an input connected to it and sending data and an amp connected to the output and switched on with speakers connected to the amp? Can any of that be skipped so that it can be run in silently over several nights without an excessive electricity bill at the end?

Also, if the DAC has multiple inputs and outputs (like the Beresford TC7520), does each input that I intend to use need to be run-in seperately or do they share the components that benefit from running in? The same question would apply to the outputs, including, in the case of the TC7520, the headphone output. I understand that the headphone output, when engaged, stops one of the other outputs so if the outputs need to be run in separately then I guess I wouldn't be able to run in multiple outputs at once?

Many thanks,

Simon.

NRG
25-03-2009, 16:58
No, if your CD can be put on repeat or if you stream from PC/MAC and can enable a repeat function or simply play your whole HDD music collection, connect up to the DAC select the correct input and press play...you don't need the amp and 'speakers to be on. The 7510 still took an age to fully run in but it was very lisenable after just a few days...

DSJR
25-03-2009, 17:08
I'm honestly wondering if the thing needs to be fed a signal 24/7. Some fussy electronics come on song just by being left powered and as the "electrical annealing" takes place, the warm-up time from switch-on gets manageable too. Anyone telling you that Naim takes five days plus to come on song once well run in for example needs to get their stuff re-aligned, as it's almost certainly drifted off.

Perhaps Stan can confirm if my suggestion of just leaving it on for a few weeks is sufficient.

By the way, your ears/brain/mind will take a day or two to adjust to any differences you may or may not hear and this can be confused with changes in equipment when it actually isn't.......

leo
25-03-2009, 19:59
If the dacs output stage uses say a +v rail supply the Coupling caps as well as all the decoupling caps will always have a DC bias on them, you don't need any signal to form the caps etc when run like this, just make sure theres some sort of load on the dacs analogue output (can be plugged into a switched off pre/amp) and leave the dac powered up
Some people like to switch the thing on and a off a few times a day too, the recharging and discharging of the caps may or may not speed up the burn in process

markf
26-03-2009, 02:31
You need to find some way for the DAC to read and convert all the possible input values ,ie 0 to FFFF if it's 16 bit
0 to FFFFFF if it's 24 bit. Not sure if playing music will actually hit all the values ,you will probably get there by playing alot of your collection,
but it would be quicker to use a set of test signals.

kalozois100
26-03-2009, 05:17
I think the burn in period for a Dac is part of the magical experience of getting one. When i moddified my tc-7510 i had to burn it in again due to new opamp and caps. Unlike when i bought it new ( and wasnt aware of the importance of burn in) i was not dissappointed when i first hooked up the Dac. Many who buy External Dacs of different makes and price ranges are dissappointed when they first hook up a new fresh Dac. once i realised it worked o.k. i put the cd to dac on repeat and silenlty left it on for 4 to 5 days. in the mean time i listened to alot of vinyl again that i had not for quite a while whilst it was burning in. This also gives you a good reference point when you finally listen to the burn't in Dac. when the dac sounds extremely close to the that of the vinyl sound you realise what a bargin the dac is for the price and the enjoyable sound ( with a good transport) it can offer!!! :)

foxysounds
30-03-2009, 11:40
So, to summarise:


Depending on the design of the DAC it may or may not need an amp connected while burning in
If an amp is connected it does not need to be switched on


So, does it matter which set of outputs the amp is connected to?

Does each input have to be burned in separately?

Thanks,

Simon.

StanleyB
30-03-2009, 13:14
So, does it matter which set of outputs the amp is connected to?

Does each input have to be burned in separately?

You don't need to have the amp on during burn in, and you can use any input.

Stan

Ali Tait
30-03-2009, 13:28
Just plug a source into it,a cd player or pc,turn both on and play music.No need to attach amp etc.

leo
30-03-2009, 19:30
Depending on the dacs output its sometimes best to plug it into something just to add a load, especially if it uses Coupling capacitors, the amp can be switched off

The Vinyl Adventure
30-03-2009, 20:14
when i got my first "hifi" it was suggested to me that i set the speakers up facing each other and reversed the polarity of one of them so as they would be moving in same direction as each other when face on... if that makes sence. this way i could leave them on all night at a slightly higher volume than if they were facing out into the room and they would burn in quicker. to this day im not sure if he was pulling my leg. i did it none the less!
these days i just put a cd on repeat at a volume that wont intrude. but even that is only when some clown turns my naim system off and it gets left off over night and sounds bloody rubbish in when i find out, shout at people, and turn it back on again in the morning.
in most cases as kalozois100 points out the burnin is part of the experience of hifi buying

and dont let anyone tell you its all in our heads, i guaruntee that with the right equipent it would be possible to measure a difference in the sound from my set up even when its just been left switched off (i know this is slightly different to "burning in" but im sure some of the same priciples must apply)

leo
30-03-2009, 22:36
Running them like that is supposed to cancel each other out , gives the drive units chance to loosen up without sounding too loud

foxysounds
31-03-2009, 11:41
Many thanks for the advice everyone.

I should be ordering the DAC later this week. I'm pretty sure it will be Stan's new model because I was also thinking of buying a higher quality audio card for one of my PCs and Stan's new DAC would do both jobs.

Regards,

Simon.