[Little Bear]

Thank you.

Verite closed are my headphone of choice so there goes that money I may have saved

I think you should get more than one opinion before leaping to a decision. I happen to have the Crackatwoa and it's amazing with my ZMF Auteur and HD800S. I was thinking of building a Mainline but the C2A is so enjoyable that I no longer have an interest in the Mainline.

The Crackatwoa is OTL, and Mainline is SET, so the Mainline can drive a wider range of headphone impedances. Mainline also has a less tube-like sound signature than the Crack/C2A do.

If you think you'll want to use low impedance planars with the amp, I suggest the Mainline because it will drive any type. If you only want to use higher impedance cans like the ZMFs and Sennheisers, I suggest you build a Crack first. With Speedball it's only $415, and you can build it in a day. It's sound will be closer to the Crackatwoa than the Mainline, because it's an OTL. If you love the sound, sell it on head-fi and buy the C2A. If you think it's two warm or tubey, buy the Mainline. That's the way I'd approach it. The bonus of building the Crack first is that you'll have some practice with BH kits before diving into the more complex amps they offer.

 

[Audioraider]

I am going down the cap rabbithole first the red and gold Audio Research, they are really rich and big sounding but the base seems to be a little loose. I burned them in around 200 hrs, not enough to reach their full potential but enough to get a feel for them. then based on what Jamie has been doing with Duelund bypass caps I added some V-cap .1uf to bypass those. Didn’t really know what to expect but I have to say the highs are substantially better, I was rather shocked. Doc told me to watch out for smearing when I bypass those 10uf caps but I haven’t heard any smearing or ringing so far.
today I removed those and threw in some Audyn tri-reference 15uf caps. These are monsters but I moved the boards forward and fit them in. I have ordered some Jantzen silver Z caps 15 UF. That I will try in a few weeks.
I’m also going to order a pair of the Duelund silver bypass caps that Jamie is using and try those in combination with these capacitors. I’ll report back my findings.

 

[Audioraider]

I think you should get more than one opinion before leaping to a decision. I happen to have the Crackatwoa and it's amazing with my ZMF Auteur and HD800S. I was thinking of building a Mainline but the C2A is so enjoyable that I no longer have an interest in the Mainline.

The Crackatwoa is OTL, and Mainline is SET, so the Mainline can drive a wider range of headphone impedances. Mainline also has a less tube-like sound signature than the Crack/C2A do.

If you think you'll want to use low impedance planars with the amp, I suggest the Mainline because it will drive any type. If you only want to use higher impedance cans like the ZMFs and Sennheisers, I suggest you build a Crack first. With Speedball it's only $415, and you can build it in a day. It's sound will be closer to the Crackatwoa than the Mainline, because it's an OTL. If you love the sound, sell it on head-fi and buy the C2A. If you think it's two warm or tubey, buy the Mainline. That's the way I'd approach it. The bonus of building the Crack first is that you'll have some practice with BH kits before diving into the more complex amps they offer.

I don’t have the Auteur but the vérité closed is a dark headphone. I Tried them with an upgraded crack with speedball and did not like them. Way too dark and mushy. I’m currently swapping out caps in my mainline to try and brighten up the signature. It is a fairly neutral amp but I need more top end to compensate for the dark nature of the vérité Woody’s.

 

[Audioraider]

It's been a while since my last post here hope you guys are all well.

Something for the cap junkies here.

I had been thinking bout trying the Duelund silver foil bypass capacitors in my Mainline for a while now after installing the Duelund Cast Copper capacitors in my Bottlehead Eros phono stage a few years ago and being impressed with the results.

Duelund very recently announced a new versions of both their silver and copper foil bypass capacitors along with cutting the price by 50% due to improved synergy after taking over Jenson who were undertakening the winding of them for Duelund.
The new improved version is called the Duelund JDM (Jenson Domestic Market).

At the new price (£35 each here in the UK) I couldn't resist the temptation to give them a try. After installing the silver foils in bypass configuration onto the 10 uf RTI Teflon Tin foil capacitors I have in my Mainline I have been listening to tunes through them for a few days now.

Current chain
Roon Rock (all SSD) >Oppo205 DAC >Bottlehead Mainline amp> Sennheiser hd800 (balanced cable)

These silver foils are really quiet something the difference has been significant and across the board from top to bottom.

It's hard not to gush but in all honestly it feels like I am listening to a different dac and that's not some thing I expected to be saying or say lightly.

For clarification I purchased the Duelund JDM Silver foil capacitors with my own money from their authorised distributor here in the UK and have no other financial connection with them.

Congratulation to Duelund for making such a superb product available at such a affordable price.

Jamie, I’m hoping you can help me because I’m thoroughly confused at this point. Regarding what side the outer foil connects to in the mainline. On the bottlehead Forum people make contradictory statements. in this pic, it appears to me, you have the Duelund inner foil connected to 20 and 30 but the Teflon cap seems reversed With the outer foil connected to 20 and 30? I currently have my caps oriented with the inner foil connected to 20 and 30 (the tube side) and the outer foil connected to the transformer side. Is this correct?

 

[Audioraider]

On the Duelund website it says they should be oriented a certain way: “The outer lead out, closest to the edge of the capacitor, is connected to the outer foil and as such should be connected to the lowest impedance path to ground, generally the signal output.” I think means the outer foil goes to the tube side 20 and 30? That means we both have them in backwards? Not sure if this even affects the sound but I would like to install them correctly.

 

[JamieMcC]

Think I was in a rush to solder them in before my kids got back from school and as I didnt have access to my manual they just went in. So it wouldn't be a surprise that the outer foil was not orientated correctly. I'll swap them round at some point.

 

[DenverW]

I dont think there will be an audible difference in the orientation of the caps, but I also want to have them oriented properly, I’m running 10uf auricap XO with duelund silver bypass caps. Really burning into a coherent sound On my mainline, Using Hd800 And zmf auteur.

i have a crackatwoa kit that I’m building, so I’ll eventually be able to give comparisons, but I’ll probably wait until I upgrade the crack2a to the level that the mainline is upgraded to make it a fair comparison.

And I get to try out a new tube type , the 6005/el90/6aq5! If anyone has any opinions on the best of these let me know!

 

[hikaru12]

Does anyone happen to know the dimensions of a stock Mainline? I’m trying to decide on it or the Crackatowa for my Stellias which are super low impedance (35 ohms).

 

[Audioraider]

Does anyone happen to know the dimensions of a stock Mainline? I’m trying to decide on it or the Crackatowa for my Stellias which are super low impedance (35 ohms).

14x14
I own the mainline which is fantastic with low impedance headphones like the Stellia I don’t think the Crackatowoa would be a good match.

 

[NYer718]

Does anyone know how well the Mainline would pair with the Apogee MiniDac with a set of HD650?

 

[DenverW]

Does anyone know how well the Mainline would pair with the Apogee MiniDac with a set of HD650?

Great with the 650, but no idea about the dac.

 

[Lohb]

Anyone use the Mainline with LCD-XC or DCA AEon 2 in XLR mode ?

Does it have the juice to power these planars into a quality SQ zone ?

 

[SilverEars]

Anyone use the Mainline with LCD-XC or DCA AEon 2 in XLR mode ?

Does it have the juice to power these planars into a quality SQ zone ?

Mainline is weak for what you pay for. I would go for a solid state for the planars. Mainline XLR is single ended, so it makes no difference.

 

[Tom-s]

Mainline is weak for what you pay for. I would go for a solid state for the planars. Mainline XLR is single ended, so it makes no difference.

It's not correct what you state here. It does have a switch to allow a balanced output from the output transformer secondary windings.

It can be run both balanced and as single ended. With the XLR output connect one can use both options via a switch.

 

[baseonmars]

Anyone use the Mainline with LCD-XC or DCA AEon 2 in XLR mode ?

Does it have the juice to power these planars into a quality SQ zone ?

The SEX set to 4ohms was supreme with the original Aeon closed... I guess that's not what you asked directly but I haven't heard them sound even remotely as enjoyable on another amp - I think they really need more juice than most people give them.