[SoundFreaq]

I am ordering my M3 for my 5Ks and everyone I talked to recommended the OPA627/637 combo. The builder (Stephen S. of Rockhopper) recommends OPA627 since you won't have the gain constrictions that the OPA637 present. He says the output gain may be a little high with the 637. Thoughts?

Also, he recommended a gain switch instead of the variable bass boost because "they really didn't need it". But, I'm a bass head, so any experiences there?

Thanks guys, appreciated as usual.

 

[Iron_Dreamer]

Hey, nice to see another Austinite head-fier

IME the 637's aren't worth it over the 627's, but I haven't heard them in an M3 FWIW.

As far as the bass boost goes, what are you currently using the SA5K's with, and do you currently ever find them lacking in bass? I can see a bass-boost being useful if you want that DT770-like huge bass experience every once and a while, while keeping the SA5K's more neutral signal most of the time. Of course if you were just after inevitable huge bass all along, perhaps there were better cans to get.

 

[SoundFreaq]

Oh no, I don't just want huge bass... I want that controlled, articulate, detailed tight bass the 5Ks deliver. I couldn't be happier with them. I just like a lot of that nice bass. I am using them now with an interim cmoy amp (i know, i know) and yes, I find them lacking. I listen to a lot of extended bass production music (electronic) and I basically want someone to tell me why a gain switch would be better than a variable bass boost that I can control to my hearts desire.

The 627s eh? hmm...

 

[spike33]

The best combo is 627 on ground, 8610 on L/R. Everyone knows that!

 

[SoundFreaq]

seriously now...

 

[DeeJayBump]

First off, I can't speak to either the SA5K or the M3.

My comments will be about the bass boost and 627/637s. I've had the BB/TI OPA637s in two headphone amps so far, and find they suit both my preferred 'phones (Grados, but a pair of CD3Ks is on the way) and my listening tastes. For me, they were worth it over 627s. Only you can decide if they are for you.

Bass boost is a valuable feature and has nothing to do with whether or not your headphones or your preferred opamps reproduce bass well. For that matter having variable bass boost on your headphone amp also has nothing to do with whether or not your source extracts deep, textured bass information. There are alot of CDs out there with poor mastering that has completely stifled/erased/minimized the bass information that existed in the original performance.

It is for these poorly transferred or poorly mastered recordings that variable bass boost can be an indispensible feature. A simple flick of the knob can allow you to restore some of the lost bass information. If, like me, you have quite a few CDs that need bass boost, you will wonder how you ever lived without this feature.

Of course, you can also just crank the VBB on albums that already have great bass to take it over the top, too. Just let someone try to stop you. So, variable bass boost can be used for purely practical reasons, or it can be used simply for fun.

 

[Jazper]

I actually have an m3, and sa5ks, in the m3 at the moment is the 637/627 combo.

I find having the 627 in all channels a bit "laid back and boring" in comparison to the 637.. but ymmv.

 

[spike33]

I am serious... it is what I'm using right now.

Anyways, between 627 and 627/637, I prefer 627/637 by large margin, it is more open, more bass, more treble, overall more fun. If you like your bass, you want the variable bass boost, I don't see why you'd get gain switch (useless imho).