How do activate bass boost/gain? I do not know how to put jumpers in or out.
A guide for a noob would be greatly appreciated.
Yes.. gently pull them with a pair of needle nose pliers. The jumpers are in pairs b/c each jumper is for a (left & right) channel. I can't remember if the red jumpers are for the bass boost or the black jumpers are for gain.. but you can insert/pull them "on the fly" (while the amp is powered on & being used), so you'll figure out which one is gain and which is bass boost very quickly.
I almost never used the high gain.. and I had the gain on my V4 lowered to 1.5x/4.5x (so it would suit IEMs better).. in low gain, it drove the HE-500 with serious authority. I don't think I cracked 12 o clock on the pot... and it wasn't just 'loud'.. there was excellent dynamics, control, and all that on the low gain setting. I didn't fiddle with the bass boost either.. left it off for the most part (but it's extremely enjoyable when enabled.. as I've said before, it's one of the most elegant bass boost circuits I've heard in an amp).
I found that to change/improve with use (on the high gain), actually.. and not the first amp I've experienced such a phenomenon on.
That's been my experience with the V4.. and other amps I've owned. Not anything drastic.. but a noticeable smoothing effect after some time of use (again, to my ears).
Sorry Mython, I have no experience with the Portaphile 627, only the NECO V4. And I am quite happy teaming my HD650s and older 420s with that amp. In reading reviews on the Portaphile I see that the writer quoted $550. I paid MUCH less than that for the V4 and Neco is fun and helpful. Hope you can get your comparison to Portaphile. cheers, alejandro
Definitely interested in this. Love the idea of being able to take this with me to the cottage, and having stellar sound. Does anyone here have any experience with the different op-amps? Reading descriptions, it seems like the ADA4627 might be the sound I am looking for as I am willing to sacrifice a bit of resolution for a richer sound - especially in the all-important midrange.
I don't know if you bought your Nano already - but You could also consider 2 other options:
1) the Astell Kern AK100 - to my mind a great little DAP with 32 GB storage onboard and 2 Slots for SDCX cards. officially each has 32 GB - but many (me too) use 64 GB cards. This way You could store a lot of lossless Jazz -Files. The downside is the pricing of corse- but I would assume that with the "next big thing out"- the AK40 (with a ridiculous price) there will surely be some guys here selling it for maybe 400 USD.
2) Also a look at the Fiio X3 - it can also play 24/192 files and costs around $199 - in the beginning it had a somewhat slow and not completely "finished" User Interface. Buit its flaws should have been mended by now.
Both would surely give You a lot of listening fun.