[Tom Steed]

I have just put a pair of Burr Brown OPA2134PA opamps in and they sound good with the mullard e180f's. I'm waiting for a pair of muses02's to try. If they don't work so well i can always try them in my soundcard.

 

[dhaninugraha]

Looks like I'll be picking up a few pair of opamps from Mouser within 1-2 weeks: OPA2134, OPA2604, OPA2227, LM4562.
Valvo and Mullard tubes also comes to mind.

I think I need to cancel my PayPal account and credit cards...

 

[Tom Steed]

I have just put a pair of Burr Brown OPA2134PA opamps in and they sound good with the mullard e180f's. I'm waiting for a pair of muses02's to try. If they don't work so well i can always try them in my soundcard.

So i decided to get a pair of hd600's. Yes it was worth it. I play flat don't use eq and it's all there. Bass, mid's and high's but nothing is overpowering. A well balanced sound. I.m using the burr brown opamps with amperex 6688's with absolutely no complaints. I have a few more bits arriving soon and will see if the sound picture changes any.

 

[erich6]

I just got the HD6xx and I can report they pair well with the Nobsound NS-08E and Amperex JEP-6688's. This little amp has plenty of power to give and lots of headroom with the HD6xx.

 

[edulov]

Just a comment about Burr Brown's compatible with this amp. They produce a darker sound. Not so accentuated, but I prefer neutral sound right from the gear.

 

[edulov]

This tiny guy can kill your ears even in 600 Ohm cans. That is why some people were crying that it lacks gain switch to deal with low-high ohm headpnones w/o touching volume button,

 

[dhaninugraha]

These babies just came in the mail. Left my hex keys at home though... Won't be able to try them out in the NS-08E until sometime tonight. *sigh*

 

[Tom Steed]

These babies just came in the mail. Left my hex keys at home though... Won't be able to try them out in the NS-08E until sometime tonight. *sigh*

I got a pair of these to try today as well

 

[dhaninugraha]

I got a pair of these to try today as well

Cool! Which tubes are you pairing them with? I'm currently listening to them with the stock tubes on.

 

[Tom Steed]

Cool! Which tubes are you pairing them with? I'm currently listening to them with the stock tubes on.

At the moment NOS mullard e180f's. I have 6688's to try as well and should be getting some Russian tubes soon.

 

[Tom Steed]

So i decided to get a pair of hd600's. Yes it was worth it. I play flat don't use eq and it's all there. Bass, mid's and high's but nothing is overpowering. A well balanced sound. I.m using the burr brown opamps with amperex 6688's with absolutely no complaints. I have a few more bits arriving soon and will see if the sound picture changes any.

Today i received a pair of dual opamps to try from Charles at Burson Audio. They are V5i hybrid amps, a mix of discrete components and a custom integrated circuit. They are a drop in component and can replace a multitude of differing opamps.

The website states that they need a 'burn in' period of around 100hours. Which should be about 5-6 days as i don't turn the nob off.

My headphone amp is connected to the soundcard in my pc and my music is digital files, blu ray audio and streaming and other file formats. I use an ASUS Xonar essence stxII into the nob with e180f tubes output to HD600's and my first impressions, well it brought a smile to my face. The first file i played was 'on the run' from the pink floyd immersion box set. This is one of the busiest tracks i know, so much going on and everything was there in my ears. The headphones provide the soundstage and the amp drives it. I think it's a perfect match and hope it's gets better as they bun in.

 

[Slipmyster]

They look the business. Really neat.
I have a question about the volume pot if anyone can help.
Mine seems to have a bit of an imbalance toward the right hand channel is it possible to drop in an alps pot ?
Are they the same size ?

 

[edulov]

... a bit of an imbalance toward the right hand channel ...

Most probably (99%) a disbalance resides in slightly different (or even not so small) REAL electric specs of the tubes. It happens even for the NOB's, not even speaking about a weared second-hand. That is why many people pay extra for selected pairs, since a special testing device measures a set of electric specs for each tube and we can make the most equal pairs.
If disbalance is not so big and your audio source has a precise L/R balance control (ALL modern digital sound cards and operating systems offer this feature), make a realtime recording, measuring the signal strength for L and R, adjusting it through OS mixer or special sound driver feature.
Even more, some people don not recommend to use full sound card amplification (so called 100%), using 70-80% interval, where you can adjust your disbalance easily. Do not forget, that our amd is really powerful and you can compensate a volume drop turning an amp's knop instead of amplifying a sound card noises.

Tell us, if it helped.

 

[Slipmyster]

Most probably (99%) a disbalance resides in slightly different (or even not so small) REAL electric specs of the tubes. It happens even for the NOB's, not even speaking about a weared second-hand. That is why many people pay extra for selected pairs, since a special testing device measures a set of electric specs for each tube and we can make the most equal pairs.
If disbalance is not so big and your audio source has a precise L/R balance control (ALL modern digital sound cards and operating systems offer this feature), make a realtime recording, measuring the signal strength for L and R, adjusting it through OS mixer or special sound driver feature.
Even more, some people don not recommend to use full sound card amplification (so called 100%), using 70-80% interval, where you can adjust your disbalance easily. Do not forget, that our amd is really powerful and you can compensate a volume drop turning an amp's knop instead of amplifying a sound card noises.

Tell us, if it helped.

Mine is connected to a Sony cd player so source isn't a problem.
I bought 2 matched pair of Russian 6j9's. The pair that is in now only have a few hours on them so I'm going to get the other pair out tomorrow and give them a try. May be swap them around a bit and see if i can level it up.
Thanks for the help

 

[edulov]

Warming up is happening for valves, but normally we are talking about 15 minutes max after swithing on. Measuring by ear is not a good idea actually. Download RMAA, they implemented realtime amplitude measurement for L/R, so you can see levels on the go.