Some issues with the SMSL 793-II and the O2+ODAC (JDSLabs, though) that I need some help on diagnosing the problem. Yeah, I need help.

[TumbleButt]

So, yeah, I emailedmessaged SSL about using the SMSL as a DAC for the O2+ODAC since my O2+ODAC is starting to hiss like nuts and I'm not sure if my SMSL is supposed to start clipping hard at 3 o'clock.

Here are the headphones I've used with it:

NAD Viso HP-50
Shure 1840

Sennheiser HD600




Experience:

O2+ODac: I hear hissing starting at 8 o'clock, which is my usual sweet spot for my sensitive ears (sensitive to sound quantity more often than sound quality in terms of volume), on all three of my headphones

SMSL 793-II: No issues whatsoever with the 1840's and the HP50's, but I do not know if the 793-II is meant to power high impedance, low sensitivity, and/or inefficient headphones (I honestly think the HD600 is not insensitive or inefficient to not run properly on this, but I'm not exactly sure), in which I hear a fair lot of clipping at 3 o'clock. I do not know if the manufacturer's intend this to not power headphones like the HD600. 


Could one or both of them have the problem? I don't wanna go and conclude that the HD600's have the problem, but I have no other amps and/or dacs to use it with.

[xtroria]

You sir, have 2 defective products. My O2 doesn't clip at all unless i want to try to blow my ears off and HD600 gets plenty loud as in unbearably loud with iBasso D-zero plugged which has way less power than SMSL

[TumbleButt]

You sir, have 2 defective products. My O2 doesn't clip at all unless i want to try to blow my ears off and HD600 gets plenty loud as in unbearably loud with iBasso D-zero plugged which has way less power than SMSL

Well... holy shit.

Now I remember why I don't like buying anything sold locally, either be it made somewhere else or built locally. The guys here don't do much QC themselves.

[xtroria]

Well... holy shit.

Now I remember why I don't like buying anything sold locally, either be it made somewhere else or built locally. The guys here don't do much QC themselves.

 

Who made your O2?

[TumbleButt]

Who made your O2?

JDSLabs.

I'd love to get a Mayflower one, but the goddamn handling tax-fee here, man... fucking hell.

[iShad]

JDSLabs.

I'd love to get a Mayflower one, but the goddamn handling tax-fee here, man... fucking hell.

+1 for they're both defective. I had the combo from JDS labs for 2 years and it worked well, never had hissing problem. Also had a pair of hd650; I remembered powering it with just onboard sound and it was more than adequate.

[SSL]

I don't know the detailed performance of the SMSL; given that the HD600 is 300 ohm, it seems most likely that the clipping would be due to excess gain if you are cranking the volume way up.

 

That of course assumes that the unit isn't defective.

[TumbleButt]

I don't know the detailed performance of the SMSL; given that the HD600 is 300 ohm, it seems most likely that the clipping would be due to excess gain if you are cranking the volume way up.

 

That of course assumes that the unit isn't defective.

Well I had to crank the SMSL to 3 o'clock to get the equivalent 8 o'clock from the O2+ODac, which I've never done on the O2+ODAC (until it just went full retard and started hissing like no tomorrow at 8 o'clock). My usual volume setting on the SMSL with the other headphones are just barely above 8 o'clock.

Could be both of my DAC and AMPs have some defect. Its strange, before I got the HD600's, I've used both of the DAC+Amps with 650's, and around 8:30-ish/inbetween 8 and 9 or sometimes 10 depending on what fuckups happened on the recording/mastering/producing/etc... of the track I was listening with, was already loud enough on the O2 and pretty much the same story with the SMSL, albeit at times I did have to crank it to 11 o'clock, but thats pretty much like 4/10 in terms of volume (not score, just level, just incase someone pokes me with a pitchfork @.@), so it shouldn't be that high.

I may have to send both in for atleast a checkup on whats wrong. And yeah, I've never switched the gain on on either one.

[pas008]

Headphones ok on other stuff?

[KaminKevCrew]

Well I had to crank the SMSL to 3 o'clock to get the equivalent 8 o'clock from the O2+ODac, which I've never done on the O2+ODAC (until it just went full retard and started hissing like no tomorrow at 8 o'clock). My usual volume setting on the SMSL with the other headphones are just barely above 8 o'clock.

Could be both of my DAC and AMPs have some defect. Its strange, before I got the HD600's, I've used both of the DAC+Amps with 650's, and around 8:30-ish/inbetween 8 and 9 or sometimes 10 depending on what fuckups happened on the recording/mastering/producing/etc... of the track I was listening with, was already loud enough on the O2 and pretty much the same story with the SMSL, albeit at times I did have to crank it to 11 o'clock, but thats pretty much like 4/10 in terms of volume (not score, just level, just incase someone pokes me with a pitchfork @.@), so it shouldn't be that high.

I may have to send both in for atleast a checkup on whats wrong. And yeah, I've never switched the gain on on either one.

If you had a properly functioning SMSL, you would not have to turn it up to 3 oclock. (I have one, and tried it with my old HD650, and I can't bear the sound past 12 oclock, because it get really, really loud.)

 

For comparison, my phone can drive the HD650 louder than I like, and it could power my D7k about the same. If I cranked the SMSL up all the way, I couldn't even put the headphones within four inches of my head because of how loud they were.

[TumbleButt]

Headphones ok on other stuff?

With the SMSL, only two headphones were okay an 8 o'clock

With the O2+ODac, I got tons of hissing.

 

If you had a properly functioning SMSL, you would not have to turn it up to 3 oclock. (I have one, and tried it with my old HD650, and I can't bear the sound past 12 oclock, because it get really, really loud.)

 

For comparison, my phone can drive the HD650 louder than I like, and it could power my D7k about the same. If I cranked the SMSL up all the way, I couldn't even put the headphones within four inches of my head because of how loud they were.

Welp, I've sent both to the shop just earlier. The SMSL was deffective while the O2+Odac had "user damage" in regards to the internals, which I suspect someone else did something to it. Dunno who did it, but with the visitors I've had over these past few days, I just gotta pinpoint who owes me money this time for screwing with it.

[KaminKevCrew]

With the SMSL, only two headphones were okay an 8 o'clock

With the O2+ODac, I got tons of hissing.

 

Welp, I've sent both to the shop just earlier. The SMSL was deffective while the O2+Odac had "user damage" in regards to the internals, which I suspect someone else did something to it. Dunno who did it, but with the visitors I've had over these past few days, I just gotta pinpoint who owes me money this time for screwing with it.

That sucks man...

[TumbleButt]

That sucks man...

Its alright, I guess. I'm super tempted in getting the Emotiva Mini-X A-100 and "The Can Opener" to use as a headphone amp and converting my soon to be replaced SMSL 793-II as a dedicated DAC+secondary volume to make sure the Emotiva never runs full power. My home usually becomes an audio meetup and someone brought that big-ass speaker amp in our meetup. He bought one because of Z Reviews, and I got interested. Since my O2+Odac was tampered with, I feel that I just gotta have that big-ass amp. I mean, its $220, and I found a place that sells one locally (I wouldn't mind paying the ridiculous handling tax-fee for "The Can Opener" so I can safely use the Mini-X along with headphones without risk of frying headphones) and man... since the O2+Odac broke, I guess I got a good excuse to get one.