Grado RS-1

[azrockitman]

I don't see any reference to these headphones when i do a search.  Has anyone listened to them with a crack?  Contemplating a crack for my next future build but I need something that is a good match for my headphones.  Thanks!

[Paul Birkeland]

The Grado headphones are a pretty poor match for the capabilities of the Crack.  The SEX amp and Mainline will both work very well with the full line of Grado headphones. 

To get the Crack to work with Grados, you would have to add quite a bit of feedback, drastically increase the size of the output coupling caps, and decrease the impedance of the cap loading resistors.  All these modifications will decrease the sonic performance of the amplifier on their own.

[azrockitman]

Shoot, so much for that idea.  Thanks for the quick reply.
I like the size (and price) of the crack.  And i don't need the speaker outputs that come with the SEX as the single purpose of this amp will be the headphones. Thanks though

[Paul Birkeland]

You can leave the binding posts out of the SEX amp and wire it up as a dedicated headphone amp.

-PB

[Grainger49]

Also, you need the transformer for the low impedance phones.  All Grado phones I know of are 32 ohms. 

But there is over $100 almost $200 difference in price.

[Chris]

Yeah, I was going to say, the super low 32 ohm load is an odd and a tough one..

[Dr. Toobz]

I had the exact same issue. Until I can scrimp for a Mainline, I ended up running my Grados through a single-ended FET amp, which seems to do quite well. The Crack sounds great with my Sennhesiers, but OTL topologies are just not designed for low-Z phones like Grados. Either go solid-state for those, or look into something with output transformers, as others have stated. Personally, I never liked how Grados sounded on tubes. They seem to work best with a very low source impedance (e.g, less than an ohm), otherwise, they have a tendency to get shouty and have weird bass. This is especially true if run from a 120 ohm source impedance, like the Crack!

Another option would be to rig up a Quickie for headphone use, but even with dedicated 32 ohm secondaries I never found a way to get enough volume (despite the Grados being relatively sensitive and easy to drive).

[Mike B]

When I first fired up the Crack, I plugged in the Sony MDR-V6 as if something was amiss I didn't want to destroy the expensive Senns.

The bass was farting.  Really bad.  Plugged in the 600's and it's sonic nirvana.

The Sony's are 65 ohm too, not super low.  Will not work with Crack.

[azrockitman]

Thanks all....lots to consider.

I think more than anything, I may wait until I can hear some Sennheiser's with a crack amp.  I really like my grado's with my solid state equipment but since the affordable BH option ( crack ) won't work, then I'm left with building a SEX or Mainline.  And the SEX option is close enough in price to building a crack and perhaps buying a used pair of 650's ....that it only makes sense to hear the alternative choice first and make a decision later. 

Thanks again

[adamct]

My personal advice would be to go for HD600s over HD650s. They are cheaper and better. I've owned (and sold) three pairs of HD650s. I still own two pairs of HD600s, along with HD800s and many, many others.

Especially if you like the RS-1s, I can't imagine you liking the HD650s...

Best regards,
Adam

[azrockitman]

Thanks for the tip Adam, I'll be sure to take a listen

[azrockitman]

Questions like the one I'm about to post always annoy me.  .  NO one knows the correct best answer for a stranger but sometimes someone hits the right chord and helps the decision process so here goes. 

Sex kit. $539.  I own my grado RSI-1's so total cost is $539.
Crack is $279.   Sennheiser HD-600's just showed up on massdrop for $309. Total = $588.

Those two costs are close enough to be irrelevant in a comparison. 

I don't need either amp for anything other than headphones.

If I thought I could audition both combos soon I would do that but I doubt i can accomplish that.   

Any strong thoughts?   

[Grainger49]

The RS-1s are top of the line headphones, or were their TOTL when they came out.   There might be something above them now. 

You like these, so I would stick with them and go for the SEX amp.  IMHO!

[mcandmar]

Questions like the one I'm about to post always annoy me.  .  NO one knows the correct best answer for a stranger but sometimes someone hits the right chord and helps the decision process so here goes. 

Sex kit. $539.  I own my grado RSI-1's so total cost is $539.
Crack is $279.   Sennheiser HD-600's just showed up on massdrop for $309. Total = $588.

Those two costs are close enough to be irrelevant in a comparison. 

I don't need either amp for anything other than headphones.

If I thought I could audition both combos soon I would do that but I doubt i can accomplish that.   

Any strong thoughts?

Curious to hear what your final decision was?

I was torn between the Crack and S.E.X. amp for a long time, initially i wanted the Crack just to drive my HD650's, but in the end i ordered the S.E.X. amp for the added versatility of being able to drive my MS-Pros (RS1's cousins).  Both are very different headphones, but i love them both equally.  I am keen to hear how the S.E.X./Grado combination has worked out for other people..

[azrockitman]

I've done....nothing.   

I'm quickly running out of room in the area I house this system in my office and the sex is a "full figured" solution.  The crack has raving fans and is a smaller footprint, but the grados are very good (to my ear) and I have a hard time just shelving them to buy a new pair of headphones for a new amp.  And I didn't win the powerball last weekend so plan B is out.   

So, I will either build a SEX for the rs-1's and simply leave out the speaker terminal build-portion, that is if I can find the room...or I'll go solid state.

"Life gets in the way sometimes...."  My phono Eros project has been sitting on the counter 2/3rds finished for the last 4 weeks....mocking me daily, to finish that project.   That's job one for me right now.   As soon as I finish that, I hope to decide on the headphone solution.  Or a dac.  Damn!