[JamieMcC]

The Mainline does a good job with the LCDs, but I find myself preferring the S.E.X. That could be more a question of signatures though because I've nodded the S.E.X. for a warm sound which is also why I bought LCD 2s. The Mainline's more neutral presentation may be more the cause than its actual ability to drive the LCDs.

I'll do some more comparative listening later today and share more then.

 

[Loquah]

OK, so I've just tried the S.E.X. and Mainline with the LCD-2s (rev 2, Dec 2013) and am slightly wishing I hadn't...
 
My setup is Matrix X-Sabre feeding S.E.X. and Mainline in parallel using identical RCA cables (Tara Labs). The S.E.X. has been upgraded with Mundorf Supreme Silver/Gold Oil output caps and some FT-3 Russian Teflons elsewhere in the chain. The Mainline has Auricaps running in what is essentially the position of an output cap and the same FT-3 russian teflons running in the power regulation circuit coupled to the 12AU7.
 
In the past I've always preferred the S.E.X.'s extra power and warmth with the LCD-2s, but today's exercise had the Mainline way out in front. Details were sharper and clearer with the Mainline and the stage was more open. The treble energy and detail is better from the Mainline too, but still wonderfully smooth (a feature of the Auricaps I added, but the stock Mainline is great in this regard anyway). In the past I was craving the warmth of the LCD 2s, but I think my tastes have shifted (which seems to happen from time to time) and the Mainline is now clearly superior.
 
I volume matched as best I could by ear and the dynamics seemed very similar on both amps - it was only resolution and signature that changed so I'm confident that volume wasn't a contributing factor. I even turned the S.E.X. up so it was definitely louder than the Mainline and the Mainline still had an edge.
 
I should clarify at this point that the S.E.X. still sounds outstanding with the LCD 2s and it may just be a case of my capacitor choices smoothing things over too much... hmmmm... maybe it's time for a fresh set of caps in the S.E.X.??
 
To answer your question @adamaley, the Mainline fits the bill perfectly and does wonders with every headphone I've ever thrown at it. It's an amp that honestly does cure upgrade-itis (for the desktop amp section of your rig at least)
 
EDIT: Forgot to add that I ran both setups in balanced with the Mainline set to low impedance mode. The Mainline volume was on around -12dB so there's only 1 step left on the coarse attenuator and 10 steps total (I think) to reach full volume so if you like your ears bleeding the Mainline might lack the juice, but I doubt anyone would really want that much volume as I was probably listening at around 80dB so getting up towards full volume is long term hearing damage territory. The S.E.X. on the other hand was purring away at about 50% on the stepped attenuator.

 

[adamaley]

Thanks a lot, @Loquah. Wonderful insight.

 

[Jmstrmbn]

Got the Chinese Sino 6as7g in today.  Will post some thoughts once I've given it a few days to adjust to it's new home!

 

[Melange]

Hi everyone. I was wondering if anyone here has experience with the HD650 matched with both the Crack and the Crack with Speedball upgrade. I'm currently running my HD650s with a Schiit Modi and Vali combo. It's not bad, but I find the sound just a little bit on the lean side, for lack of any better way of putting it. I plan on upgrading to a Crack sometime in the near future.
 
My question is this: does the Speedball upgrade noticeably change the output of the Crack so that the tonal balance of the HD650 will be leaner? I hear that it improves the soundstage, timing, gives a blacker background and so forth. Now that sounds great, but what I love about the HD650 is the warm, laid-back sound with the slightly euphonic coloration in the mid-bass and lower midrange, and if the Speedball reduces this in the same way that I feel the Modi/Vali does, then I would choose not to buy it.
 
I'd greatly appreciate any input you guys could provide, thanks.

 

[Deterministic NL]

  Hi everyone. I was wondering if anyone here has experience with the HD650 matched with both the Crack and the Crack with Speedball upgrade. I'm currently running my HD650s with a Schiit Modi and Vali combo. It's not bad, but I find the sound just a little bit on the lean side, for lack of any better way of putting it. I plan on upgrading to a Crack sometime in the near future.
 
My question is this: does the Speedball upgrade noticeably change the output of the Crack so that the tonal balance of the HD650 will be leaner? I hear that it improves the soundstage, timing, gives a blacker background and so forth. Now that sounds great, but what I love about the HD650 is the warm, laid-back sound with the slightly euphonic coloration in the mid-bass and lower midrange, and if the Speedball reduces this in the same way that I feel the Modi/Vali does, then I would choose not to buy it.
 
I'd greatly appreciate any input you guys could provide, thanks.

I won't get into the science of it all but I have a Crack with Speedball and HD650's and I'm generally happy.  Sounds amazing.  My source is MacMini and Fiio E17 DAC and admittedly I bump the treble in the DAC a hair because I find it a bit lean without it.   I'm a top end guy.  I want cymbals.
 
Consequently I have a Schiit Modi / Magni and while I love it I actually prefer HD598 with it and even Sony MDR-V6.  HD650 are great but of course high impedance cans.

 

[JamieMcC]

 
I'm a top end guy.  I want cymbals.

You might like to try fitting some of these as bypasses to the 100uf output caps. Lets your cymbals shimmer all ting and no shing
 
http://www.ebay.co.uk/itm/0-056uF-500V-A-A-5-TEFLON-Capacitor-K72P6-/380940922798?pt=Vintage_Electronics_R2&hash=item58b1d92fae

 

[Deterministic NL]

  You might like to try fitting some of these as bypasses to the 100uf output caps. Lets your cymbals shimmer all ting and no shing
 
http://www.ebay.co.uk/itm/0-056uF-500V-A-A-5-TEFLON-Capacitor-K72P6-/380940922798?pt=Vintage_Electronics_R2&hash=item58b1d92fae

Thanks. I just ordered two and will give it a shot.  I always thought the Crack was a touch weak up top (with the HD650) but the Fiio E17 with the treble control is perfect for it. 

 

[Utopia]

I read the latest Hifiman HE-560 review over at Headfonia and found the following to be very interesting:
 

Surprise of the last few weeks was the nice match with the Bottlehead Crack. Usually that one doesn’t work with orthodynamic headphones at all. Here however you get tube smoothness and warmth with a slower sound but it just works for me. Good bass, smooth mids and soft treble. Love it. Volume goes almost all the way up but I quite like the result. Who would have guessed?

 
I've read somewhere that with certain tubes the Crack output impedance can get as low as 70 ohm. And the HE-560 is 50 +/- 8 ohm. Not a terribly large difference. Perhaps it's something to try?

 

[vegaobscura]

  Got the Chinese Sino 6as7g in today.  Will post some thoughts once I've given it a few days to adjust to it's new home!

Definitely interested in hearing some thoughts on these! I'm in the market for a new tube and would like to hear more about the Chinese equivalents (Shuguang 6N13PT, the Sinos, ...etc) before grabbing an old RCA or something.

 

[Keithpgdrb]

  I read the latest Hifiman HE-560 review over at Headfonia and found the following to be very interesting:
 
 
I've read somewhere that with certain tubes the Crack output impedance can get as low as 70 ohm. And the HE-560 is 50 +/- 8 ohm. Not a terribly large difference. Perhaps it's something to try?

seems like a waste of time to me.  trying to use an amp outside its peak design parameters is just an exercise in compromise.  The 560 is not difficult to drive, amps that do a great job are not expensive.  IMHO.

 

[Aeolus Kratos]

  You might like to try fitting some of these as bypasses to the 100uf output caps. Lets your cymbals shimmer all ting and no shing
 
http://www.ebay.co.uk/itm/0-056uF-500V-A-A-5-TEFLON-Capacitor-K72P6-/380940922798?pt=Vintage_Electronics_R2&hash=item58b1d92fae

I just want to second this wonderful recommendation. I've just installed these caps and burned it for about 200 hours and the difference was very noticeable. The top end was clearer, more sparkling but smoother at the same time, the resolution was improved generally. And most importantly, these caps just cost you a cup of coffee. Highly recommended!
 
Thanks Jamie!
 

 

 

 

[Jmstrmbn]

Well I've put a good 15hrs on the Sino so far and the differences from the stock 6080 are starting to become clear.  In general there was an improvement in all aspects of the sound.  The noise floor is lower. The bass has evened out and is not more taught, less boomy.  The midrange seems to have retained similar character but with less bleed over from the bass can sound a bit too lean on some tracks but I find it more accurate sounding for 75% of what I've been listening to.  The highs have become much less grainy, more extended and more articulate.  I get a better sense of air in the soundstage.  The only real negative so far is that the sound stage seems wider and flatter compared to deeper and more squished, this is really track dependent so take it with a grain of salt.  
 
Overall I'm extremely happy with the upgrade for the price.  I'm not sure how long tubes typically take to settle down but I will report any differences after another week or so.
 
BTW this is without the speedball and using HD600s.  DAC is Nuforce HDP.
 
Happy listening and enjoy your Cracks!

 

[JamieMcC]

  I just want to second this wonderful recommendation. I've just installed these caps and burned it for about 200 hours and the difference was very noticeable. The top end was clearer, more sparkling but smoother at the same time, the resolution was improved generally. And most importantly, these caps just cost you a cup of coffee. Highly recommended!
 
Thanks Jamie!

 
Hi Aeolus, good to hear they worked well for you to!  They are a inexpensive mod to try and the effects are particularly welcome if your a Beyerdynamic T1's user, at times the T1's can have to aggressive top end with particular tracks/artists which can result in them being prone to some cringe worthy sibilance. With the addition of the Teflons their Achilles heel of the sibilant treble presentation was totally resolved and the top end became noticeably more refined and resolving other areas benefit also.
 
You might like to try disconnecting a lead once you have been using them for a while to re-reference the sound of the 100uf's with out them, it was a bit of a shock!  Mine went back in the circuit  pretty quickly.

 

[skeptic]

   
Hi Aeolus, good to hear they worked well for you to!  They are a inexpensive mod to try and the effects are particularly welcome if your a Beyerdynamic T1's user, at times the T1's can have to aggressive top end with particular tracks/artists which can result in them being prone to some cringe worthy sibilance. With the addition of the Teflons their Achilles heel of the sibilant treble presentation was totally resolved and the top end became noticeably more refined and resolving other areas benefit also.
 
You might like to try disconnecting a lead once you have been using them for a while to re-reference the sound of the 100uf's with out them, it was a bit of a shock!  Mine went back in the circuit  pretty quickly.

 
Jamie - are these the ones that you have to cover with some sort of heatshrink because the outside is conductive?  You guys are seriously tempting me to give the ole crack a little update!