[sup27606]

Update: The hum has come back. To check whether it's a power adapter issue, I powered the amp from a battery pack. Dead silent. So now I am thinking of two options: (1) get a ground loop eliminator like Ebtech Hum x, or (2) IFI iPower 9V adapter. I am skeptical about the second option, since it applies significantly more voltage than 6V, but it's also the cheapest. Not sure which way to go.

 

[edulov]

6V plus/minus a little. Slightly higher is better if you can't find a good 6V adapter.

 

[sup27606]

Any suggestion on a clean PSU, that won't be too expensive?

 

[Tom Steed]

Ok, I tried this track in flac format. There was a lot of left/right positioning and all the instruments were well defined. I could separate them and they didn't blur together. That said it wasn't my fav Heep song. I prefer the Salisbury album as i knew the recording studio well and heard the acoustics first hand.

At the moment i am using Russian 6j9's with the Vi5's. They are very bright and punchy in the midrange. I will be moving to the other tubes soon. Either way with a tube and op amp upgrade this little box punches well above it's weight. Depending on budget, you can go for the Vi5's at the top end and get a chip that is designed for audio presentation or at the lower end a normal audio op amp chip and as they say 'your mileage my vary'.

My setup is pc based:
Asus xonar essence stxII
Nosound with Russian 6jn, Mullard e180f and Amperex 6688. not matched valves but i found good deals on fleabay.
Sennheiser HD600

I moved back to the amperex 6688 tubes for a while and left them to warm up. they sound smoother than the russian tubes. My ears aren't good enough to accurately describe the differences, they are all good but some are gooder than others
I finally moved back to the mullard nos e180f's and these are the ones i prefer. For me they match perfectly with the Vi5 op amp. The original nosound performs well and the china valves and op amp just work. But this thread proves that with some changes it can be much more. After months of searching op amps and valves, i think i'm dialled into the sound i like and Charles at Burson Audio put the cherry on the cake by letting me test the Vi5's. I would buy these and may do so as my sound card can roll op amps.

 

[dhaninugraha]

It's been a while since I wrote my initial impressions about the V5i SS on this amp... And now I must say that I don't wanna return the V5i SS to Charles j/k.

To echo what others have said; the V5i sounds big and punchy, has good imaging/sense of space, mids that I would say as upfront, detailed and borderline bright but very enjoyable still.

Rag'n'Bone Man's Human, Iron & Wine's Flightless Bird, American Mouth, Damien Rice's The Blower's Daughter, Sarah McLachlan's Angel, and James Blunt's acoustic rendition of 1973 exemplifies my point about the mids and details. Vocals has this... intimate presence, yet there's this sense of airiness/space, without being artificially so. I can't exactly describe it. All I can say is, I'm having a really, really good time listening to all of them on repeat, with the stock tubes + V5i SS + HD25-1 combo.

Pop and electronic music sounds good too, with just enough punch and low extension, sparkly details, and good sense of presence to make things lively. Listening to David Guetta, Martin Garrix and Clean Bandit gives the kind of feeling you get when you hear a good set of stereo playing such songs at the local AV shop: it sounds fun and makes you wanna lowkey headbang, but not the enveloping, lows-so-low-you-could-feel-it-on-your-chest club feel.

Now excuse me, I've got a playlist full of Top 40 EDMs to listen to...

 

[Slipmyster]

 

[NotMuchToLearn]

I just ordered one of these off Amazon today (or a copy of this at least). The one I ordered is found here. It's a bit odd since the pics look like a copy of this nobsound amp, except it takes 12v instead of 6v, AND the brand in the pics (Hoomya) doesn't match the brand in the description (Shuogou). Even the description exactly matches the nobsound's. Everything about this is sketchy but I wanted to try it out. Also since this thread seemed to like them, I ordered some soviet tubes from ebay and I'm excited to try them out in a week or so when they arrive:

2x 6j9p-E NOS from 1975
4x 6j20p NOS date unknown

I was tempted to buy some tesla tubes too but they were a bit much once I priced in shipping so I skimped out. I found the same Hoomya amp on Amazon's Japan site and it has stellar reviews so I really hope I am getting what was pictured in the listing.

One of the reasons I got this was because my Audiotechnica M50x's little plastic piece that holds the cups to the ears broke off so I ordered some new AKG m220s from Massdrop. Also I rebuilt my computer and the new mobo didn't have a compatible pci-e slot for my soundcard. I will definitely be experimenting with this amp and both headphones. I'm hoping the tubes will really help the quality. Also if anyone knows about the compatibility of the 6j20p tubes let me know. I bought them because they said they were equivalent to 6688 and E180F tubes and they were a steal.

 

[riffrafff]

I just ordered one of these off Amazon today (or a copy of this at least). The one I ordered is found here. It's a bit odd since the pics look like a copy of this nobsound amp, except it takes 12v instead of 6v, AND the brand in the pics (Hoomya) doesn't match the brand in the description (Shuogou). Even the description exactly matches the nobsound's. Everything about this is sketchy but I wanted to try it out. Also since this thread seemed to like them, I ordered some soviet tubes from ebay and I'm excited to try them out in a week or so when they arrive:

2x 6j9p-E NOS from 1975
4x 6j20p NOS date unknown

I was tempted to buy some tesla tubes too but they were a bit much once I priced in shipping so I skimped out. I found the same Hoomya amp on Amazon's Japan site and it has stellar reviews so I really hope I am getting what was pictured in the listing.

One of the reasons I got this was because my Audiotechnica M50x's little plastic piece that holds the cups to the ears broke off so I ordered some new AKG m220s from Massdrop. Also I rebuilt my computer and the new mobo didn't have a compatible pci-e slot for my soundcard. I will definitely be experimenting with this amp and both headphones. I'm hoping the tubes will really help the quality. Also if anyone knows about the compatibility of the 6j20p tubes let me know. I bought them because they said they were equivalent to 6688 and E180F tubes and they were a steal.

That looks similar to mine, but mine is labeled "Nobsound," like this one. It also came with Chinese 6J9 tubes. I replaced them with GE 6688 tubes (and the op-amps with NS LM4562NA parts) (not sure if I really heard a difference). Plus, I ripped out those silly blue LEDs under the tubes, lol.

 

[erich6]

I just ordered one of these off Amazon today (or a copy of this at least). The one I ordered is found here. It's a bit odd since the pics look like a copy of this nobsound amp, except it takes 12v instead of 6v, AND the brand in the pics (Hoomya) doesn't match the brand in the description (Shuogou). Even the description exactly matches the nobsound's. Everything about this is sketchy but I wanted to try it out. Also since this thread seemed to like them, I ordered some soviet tubes from ebay and I'm excited to try them out in a week or so when they arrive:

2x 6j9p-E NOS from 1975
4x 6j20p NOS date unknown

I was tempted to buy some tesla tubes too but they were a bit much once I priced in shipping so I skimped out. I found the same Hoomya amp on Amazon's Japan site and it has stellar reviews so I really hope I am getting what was pictured in the listing.

One of the reasons I got this was because my Audiotechnica M50x's little plastic piece that holds the cups to the ears broke off so I ordered some new AKG m220s from Massdrop. Also I rebuilt my computer and the new mobo didn't have a compatible pci-e slot for my soundcard. I will definitely be experimenting with this amp and both headphones. I'm hoping the tubes will really help the quality. Also if anyone knows about the compatibility of the 6j20p tubes let me know. I bought them because they said they were equivalent to 6688 and E180F tubes and they were a steal.

The 6j9p should work; not sure about the 6j20p. It's a bit hit-or-miss with Soviet tubes. I highly recommend NOS Amperex JEP-6688 (I have 1964 USA production and they sound great.)

 

[AthenaZephyrian]

Anyone know how this compares to a Little Dot I+ with rolled tubes and op-amp (or stock, I guess)? OP said it was better than the Vali, and the Vali competes with the LDI+.

And how's it stack up to its miniature, titankilling cousin, the unfortunately-unrollable NS-O1E? I found the NS-O1E goes to-to-toe with the LDI+.

 

[AthenaZephyrian]

That looks similar to mine, but mine is labeled "Nobsound," like this one. It also came with Chinese 6J9 tubes. I replaced them with GE 6688 tubes (and the op-amps with NS LM4562NA parts) (not sure if I really heard a difference). Plus, I ripped out those silly blue LEDs under the tubes, lol.

Bloody hate the blue LEDs on all my electronics. If I wanted it blue I'D MAKE IT BLOODY BLUE. [/rant] Totally interferes with the lovely tube glow. I blacked out the LED on my NS-O1E.

 

[Dan-Fi]

Hey guys, glad to see that this thread is still alive with Nob users! I just thought I'd chime in on a possible suggestion for users who like me, have been battling with the issue of background hissing on this amp. I'm sure it's something to do with the power plug or adapter (if I wriggle the power jack, I can minimise the hiss, but can still hear some) and I tried different powerpoints, extension cords and adapters over the past couple or so years since I bought this amp, but the hissing persisted. So I neglected it for a long time and it collected dust by my bedside table...

Well today is Fathers Day in Oz and I got to spend some "me time" to lie in bed and listen to some music and I thought I'd try out the Nob once again. I have an LG V10 and there are posts about activating its high impedance mode to make some headphones shine on this phone and one suggestion was to use a volume attenuator, like the one Shure supplies with its higher end IEMs. You can buy this separately and I did so a while back to use my Grados on this phone. It was only today I thought (yes I'm getting older and slower with thought processes!), why don't I try this out on the Nob and see if this attenuator can mitigate the hissing? Well lo and behold, it did the trick! No hissing anymore, except if it came from the recording! I can finally listen to classical music on the Nob without any background hissing!

So now I'm back in love with this amp and listening right now to Karajan using a matched pair of Dario E180F tubes and my Grado SR325is (yes I do like classical with this headphone!). Hope this helps out for some of you Nob users!

 

[erich6]

Hey guys, glad to see that this thread is still alive with Nob users! I just thought I'd chime in on a possible suggestion for users who like me, have been battling with the issue of background hissing on this amp. I'm sure it's something to do with the power plug or adapter (if I wriggle the power jack, I can minimise the hiss, but can still hear some) and I tried different powerpoints, extension cords and adapters over the past couple or so years since I bought this amp, but the hissing persisted. So I neglected it for a long time and it collected dust by my bedside table...

Well today is Fathers Day in Oz and I got to spend some "me time" to lie in bed and listen to some music and I thought I'd try out the Nob once again. I have an LG V10 and there are posts about activating its high impedance mode to make some headphones shine on this phone and one suggestion was to use a volume attenuator, like the one Shure supplies with its higher end IEMs. You can buy this separately and I did so a while back to use my Grados on this phone. It was only today I thought (yes I'm getting older and slower with thought processes!), why don't I try this out on the Nob and see if this attenuator can mitigate the hissing? Well lo and behold, it did the trick! No hissing anymore, except if it came from the recording! I can finally listen to classical music on the Nob without any background hissing!

So now I'm back in love with this amp and listening right now to Karajan using a matched pair of Dario E180F tubes and my Grado SR325is (yes I do like classical with this headphone!). Hope this helps out for some of you Nob users!

Happy Father's Day and glad this setup works for you. I've noticed that high impedance headphones won't pick up the power source noise but low impedance cans will. It's annoying because the amp sound quality is excellent otherwise. I was going to try different power sources but looks like you've tried that to no avail.

 

[Dan-Fi]

Thanks @erich6 for the well-wishes. The highest impedance headphone I have is an old AKG K145/S which I think is rated at 200 ohm, but I could still hear hissing with them. However, as you'd indicated, higher resistivity certainly lowered the volume of the hissing. You can get one of those Shure volume attenuators on Ebay for about AUD$20-$25 when I purchased one a while ago.

 

[riffrafff]

I ran a wire from the case to NEMA-ground to eliminate the hum I was getting on mine.