[panda-R]

thanks buddy for your opinion... i think I will try Grado sr225is one of these days, but now i need to enjoy my HD650 and LC combo.
 

 

[Mad Max]

Quote:

... Usually, the difference that we hear is only because the coloration made by our systems. There is no ideal system. And when I read something: "This headphones have flat characteristic. So sound must be perfect!" it reminds me how blind (deaf) can someone be. Because there is no flat characteristic. It does not exist! Especially when in that story are involved lots of components. It is not a point to have headphones with flat characteristic. It is a point to know what kind of characteristic will give you headphones with DAC, cables and amplifier together. And that information is reserved for people who have proper measuring equipment, witch price has many zeroes.

Indeed, but you're not listening to your system as a whole if you are rolling opamps, cables, headphones, and so forth and listening to the changes to deduce a component's relative individual character.
Much cheaper than using expensive measuring equipment that can hear things that our flawed ears cannot.  =p
 

 

[tyoung8]

I really love the Grado 225 for rock as it makes the music so in your face and fun sounding.  The only problem is that I think maybe with 'forward' headphones, I would find it v fatiguing to listen for time... at least that is the case with my Superlux 662.  Wonder if that is true for Grado headphones as well?
 
Quote:

I am using Matrix Mini-I to the lovely cube with OPA627 and I really like this combo. You wont' be disappointed. 

yep, that is deffo the combo I am angling for at the moment.  

 

 

[BlaBlaBla]

endas
 
Quote:

I really love the Grado 225 for rock as it makes the music so in your face and fun sounding.  The only problem is that I think maybe with 'forward' headphones, I would find it v fatiguing to listen for time... at least that is the case with my Superlux 662.  Wonder if that is true for Grado headphones as well?
 

yep, that is deffo the combo I am angling for at the moment.  

 

True. OPA627 is good opamp. It has warmth and deep soundstage. I tried it with ATH AD900 and it is better match than with Grado SR225. ATHAD900 do not have deep sound stage, but wide. And they have good synergy (space wise) with OPA627.
 
Grado SR225 do not have wide sound stage and they sound (on OPA627), deep but closed. For Grado, better match is OPA2107.
 
I think that Matrix Mini I has warm sound stage, and lack of details. I feel that Matrix with OPA627 tends to behave in the same way (if we compare it to more bright OPA2107). So I go towards OPA2107 because I am always trying to find good combination between "bright and detailed" and "warm and mellow" components. I also think that OPA627 shines in old school amplifiers paired with very detailed DACs, because it gives to the sound more warmth and sweetness and masks harsh and sterile approach straight from the DAC output.
 
Sorry for my bad english.
I do not have time to recheck what I have allready written.

 

[BlaBlaBla]

I changed OPA627 with LME49720HA. Metal case.
That opamp is good. Very good.. Maybe too bright in combination with Grado SR225, but shows a lot more details than OPA627AU and OPA2107. Drawback is total absence of warmth, that have all BB opamps. Sound stage is between OPA2107 and OPA627. Positioning is good.
 
I have to wait 10 or 20 hours of playing to see more...
 
 
What comes first on my mind is that LME could be great with "dark headphones". So people who have Sennheisers or something like that they should try LME47920HA. It is totally different world than all Burr Brown OPAMPS...
 

 

[tyoung8]

Yeah, I am looking for warmer dac because ultrasones are kinda cold.  Does anyone know what the little dot dac 2 sounds like?

 

[BlaBlaBla]

Quote:

I changed OPA627 with LME49720HA. Metal case.
That opamp is good. Very good.. Maybe too bright in combination with Grado SR225, but shows a lot more details than OPA627AU and OPA2107. Drawback is total absence of warmth, that have all BB opamps. Sound stage is between OPA2107 and OPA627. Positioning is good.
 
I have to wait 10 or 20 hours of playing to see more...
 
 
What comes first on my mind is that LME could be great with "dark headphones". So people who have Sennheisers or something like that they should try LME47920HA. It is totally different world than all Burr Brown OPAMPS...
 

I just do not get it... Maybe my OPA627 was "a lemon", or something, but difference is more than huge... LME really shows details. And it has excellent freqency range when music is well recorded!
 
I do not know... LME was from Great Britain. OPA627 was from China... Is the difference that big?
 

 

[Mad Max]

 
Quote:

...OPA627 was from China...

  Grab a real pair next time.  However, try OPA209, OPA1611, THS4081, and OPA827 before that, tells us what you think of them.

 

[BlaBlaBla]

All these are SOIC type. I do not want SOIC opamps.

 

[Mad Max]

But the best opamps are mostly SOIC type.  =\
"It can't be helped."
I would like it if they were DIP, then I wouldn't have to solder them to adapters.

 

[BlaBlaBla]

Quote:

But the best opamps are mostly SOIC type.  =\
"It can't be helped."
I would like it if they were DIP, then I wouldn't have to solder them to adapters.

You see, problem is that SOIC type opamps are very sensitive to heat. If you use solder wire and solder them in usual way, there is great chance to break them (overheating). Usually my soldering tool has temperature over 300/350 °C. I use "warm and fast" technique. And if I solder with lower temperature (more safety approach) then I have to wait too much.
 
With DIP 8 type I have never had a problem, because I solder DIP 8 socket, and then I insert opamp into socket. Also SMD resistors, capacitors and other fancy stuff is prone to failure because overheating. But old fashion capacitors, carbon resistors, metal can opamps and transistors can work in very harsh environment. I can almost weld them onto PCB!!!
 
 
The best way to solder SOIC on the PCB (or adapter) is to use flux and heater. Spread the flux over contacts on PCB, put SOIC on PCB (on spreaded flux) and heat up all that. SOIC pins will be "glued" to PCB.  But I do not have that kind of equipment. And it is not cost wise for me, buying equipment that cost 250 USD, for soldering (once in a year) two SOIC opamps that cost 5 USD each.
 

 

[Mad Max]

I don't use temperatures that high with my Hakko 936, Cardas quad eutectic melts very fast, and together with liquid solder, I can work very quickly without damaging opamps.
I damaged soic chips in the past with overheating, but that was a long time ago.  Practice makes perfect.  =]

 

[BlaBlaBla]

An hour ago I was trying to figure out why DC offset likes to oscillate (1-2mV) when LC is not warm. Now I know why.
 
I tried to touch metal cap of BC139C with a cold screw driver (it acted like a cooler), and when I did that - DC offset jumped from 2mV to 6 mV. At first point it looks like extra cooling is not good for BC-s. But it is not true. Cooling is good, but not when you are trying to cool only one transistor.
 
Important thing is how good is temperature spread over entire case over all transistors.All transistors must have the same temperature. So, when one BC139 (in my case) works on 100°C (and it does - working temperature for BC109/139 is 80-125°C), that means that all other BC-s must have the same temperature. Otherwise DC offset will raise sky high. It does not matter if your amplifier case is warm like stove, or it barely shows that is turned on. Important is that all transistors in it, must be equally heated/cooled! Also, I noticed that transistors with high gain are more dependent on temperature than transistors with lower gain...
 
 

 

[Majestyk]

I recently bought the LC Premium and I'm just getting around to it today.  I can't get any sound.  Is there anything I'm missing?  The blue light is on, the L&R lights, on the board, are on.  I have the CD player hooked to the input jacks.  (The outer most left ones, correct?).    Is there anything else I'm missing?  Nothing on the headphone/CD player end is the problem.
 
Never mind, user error on my part.  All is working 100%.
 

 

[Majestyk]

 
 
 
Does anyone know how difficult a fix this is?  As you can see the little round metal 'fixture', on the board, is completely out.
 
UPDATE...Yes this can be easily soldered underneath.