It had to happen eventually... capacitor upgrade question for the Mainline

[Paul Birkeland]

From the instructions from the manufacturer:

"If using as a bypass cap to ground, connect green lead to ground."

[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.
Next I have some Audyn tri-reference 15uf caps to try. These are monsters but if I move the boards forward I can fit them in. I’ve also 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 his capacitors. I’ll report back my findings.
I tried to post photos but the bottlehead forum won’t let me do that. I posted them over on headfi

[mercury128]

Hey everyone, I got the urge for another cap upgrade recently when I found a well priced pair of 800V 15uF Jantzen Superior Z-Caps on eBay. Installed them tonight and I'm noticing some really nice improvements over the Auricaps I had in there before (regular Auricaps, not XO as far as I know). The Jantzens, even without burn-in time, have a really nice attack to them that is a bit faster than the Auricaps which were really nice, but the Jantzens sound more transparent so far and I expect they'll only improve over time.

I'll provide another update after some further listening, but I can recommend these as a very affordable significant upgrade (just over $100 USD for the pair) for the Mainline coupling caps.

Hi Lachlan

I purchased a pair of the Jantzen Superior 15 uf capacitors based on your recommendation. Any tips for how you installed and secured them, as they're much larger than the previous capacitors there!

Thanks
- Alex

[AllanMarcus]

Well, I'm thinking of getting new caps. So many to choose from. The first thing I want to try is 10uf vs 15uf (maybe 20, to really emphasize the difference). I was thinking of just getting the daytons, then I will be comparing as similar caps as possible, so the only difference would be the rating of the caps. Then, if I can hear a difference I like, move "up" to a "better" cap. Does that make sense?

I found myself contemplating getting and Eddie Current Aficianado for a really good price, but a cap upgrade for the Mainline might be a better way to fulfill my urge to do something.

My Mainline has Dayton MPT 10uF 250V 5% Audio Grade caps.

Seems like the options are DMPC and PMPC. Any idea which one was shipped with the Mainline?

[Paul Birkeland]

The first thing I want to try is 10uf vs 15uf (maybe 20, to really emphasize the difference). I was thinking of just getting the daytons, then I will be comparing as similar caps as possible, so the only difference would be the rating of the caps. Then, if I can hear a difference I like, move "up" to a "better" cap. Does that make sense?

Yes, this is a very good idea.

Seems like the options are DMPC and PMPC. Any idea which one was shipped with the Mainline?

It's quite likely that the factory takes a big lot of DMPC and measures them all and the ones that are very close to the nominal value get the PMPC wrapper.  I wouldn't spend the money on the 1% caps for this application.

[Loquah]

Hi Lachlan

I purchased a pair of the Jantzen Superior 15 uf capacitors based on your recommendation. Any tips for how you installed and secured them, as they're much larger than the previous capacitors there!

Thanks
- Alex

Hi Alex,

Sorry about my slow response - I'm not here (or on other forums) as often these days. The Jantzens are a bit tricky to install. I ended up using cable tie anchors (the adhesive squares with the flat holes to take cables ties through them) and then attached the caps using a couple of cable ties joined together for length. The caps themselves then sit snugly between the 6c45pi boards and the transformers, but are not held in by the boards which is why the cable ties are necessary.

I've attached and artsy photo to show where they sit (but not how they are held in place)

[mercury128]

Hi Alex,

Sorry about my slow response - I'm not here (or on other forums) as often these days. The Jantzens are a bit tricky to install. I ended up using cable tie anchors (the adhesive squares with the flat holes to take cables ties through them) and then attached the caps using a couple of cable ties joined together for length. The caps themselves then sit snugly between the 6c45pi boards and the transformers, but are not held in by the boards which is why the cable ties are necessary.

I've attached and artsy photo to show where they sit (but not how they are held in place)

Thanks Lachlan - sounds like I did similar as I also used some cable ties and anchors to get them in there. The Jantzen's sound pretty good so thanks for the recommendation. Keep up the good work on your Youtube channel!

Thanks
- Alex

[Toobuzz]

I got around to playing with caps on the Mainline and wanted to share my impressions along with some below average pictures, and pose a question to the community.  I have some cable tie anchors on the way, but I have a surplus of 3M Dual Lock (think non-gendered Velcro but on steroids) which actually works pretty well.

Obbligato Ultra Premiums:

I used the .1uf/1000V and the 10uf/1000V and I changed them out at the same time.  @ 100 hours, I can't say that my impressions changed over that time.

• Much bigger difference that I anticipated caps would make
• Smooth and gooey, made the Mainline sound like a Crack (not really, just in that direction)
• With well-mastered modern recordings (non-acoustic instruments/vocals) goose bumps are common and my jaw hit the floor many times.
• With acoustic instruments/natural environment recordings, I am missing the fronts of the notes.  I am missing clarity.  Classical music just sounds mushy.
• Like above the bass and dynamics in general are really lacking for acoustic instruments.  The more musicians on stage the more diffuse this all sounds.
• My goodness, the 3 dimensionality is on another level when listening to pop and hip-hop (Sam Smith, Kendrick Lamar, Taylor Swift (listening for the mastering not the content  ))
• It is so odd that the 3D quality is gone with classical music.  Sounds like just another diffuse tube amp

My vision for the Mainline is to highlight it's neutrality.  While the Obbligato's were a nice journey (for very little $$$), this sound is not what I want for my Mainline.

ClarityCap CSA:

One of my goals in this initial fourrée was to try and determine the effect of using 15uf vs 10uf coupling caps.  I left the .1uf/1000V Obbligatos in place as I only purchased the 15uf/250V ClarityCaps.

• Again not a big change after the first 25 hours, which is why I feel OK posting some pre-mature impressions
• Bass is more extended.  I dislike that term. I mean that I can hear the bass region louder with slightly more detail than on the Obbligatos.
• The clarity in articulation is much better.  It is still a little more diffuse that I remember the stock caps sounding, but this could very well be the .1 uf Obbligatos that are still there.  In fact, I believe that I am hearing the Obbligatos based on that specific characteristics I am hearing.
• While it might seem that I have arrived at a nice combination, the total result is much less that the sum of its parts.  On the HD800 (stock) this combo sounds very similar to the Garage1217 Ember.   I can usually pick out the Mainline due to the size of the room vs. the space between the instruments.  Either the Ember is really good with 800 (it was my first time pairing them), or this cap combo is robbing the Mainline of some of it's best traits. I can pick out the Mainline now mostly due to that slightly diffuse articulation.
• Weight.  While I have most of the articulation back, the weight of each attack is now subdued.  Perhaps another reason why this sounds so similar to the Ember?

I'm most likely going to pull the trigger on the .1 uf CuTF V-Cap, but I am still wanting some opinions on 10uf vs 15uf for the coupling caps.  I have access to a Mainline with these V-Caps (he has the 10uf V-CAP ODAM) and I like what I hear.  Based on my experiences, I may go with the 15uf V-CAP ODAM but I wanted to see if anyone had any objective feedback.  Does moving to 15uf change the frequency response?  If so, in what areas?  Or maybe the differences between 10uf vs 15uf on the Mainline is purely subjective.  I'm curious as to other's experiences in this area.     

[Paul Birkeland]

It's not a huge difference between 10uF and 15uF.  After reading 2/3 of your post, my initial reaction was to recommend the ODAM, so I think you're on the right track.

[AllanMarcus]

I was emailing about caps with a frind of mine (crack owner), and here's what he thinks. Any of this make sense?

Are these the capacitors in series just before the output?  If so, the capacitors form a high-pass filter with the load of the headphones.  See picture.  The cutoff frequency (where the power is attenuated by 1/2 or 3 dB) is 1/2piRC.  So if the headphones are 150 ohms and the coupling cap is 10uF, the cutoff frequency is about 100 Hz.  A 20uF cap drops the cutoff to 53 Hz so you'd hear more of the very low end.

[Paul Birkeland]

There's an output transformer, so that diagram does not really apply in that way.

[Toobuzz]

Thanks for the response PB!  I wanted to put down some listening notes while it was still fresh in my head, sorry for the long post. In re-reading what I wrote, I may have come across a bit negative. Quite the contrary!  This is still very much sounding like the Mainline in all cases just with a slight tilt a various directions.  The V-Caps arrive today. My friend has a Mainline with 10uf ODAMs. I’m getting the 15uf.

[Paul Birkeland]

Oh not to worry!  The 10uF caps included with the Mainline aren't particularly expensive and it's certainly worthwhile to experiment with other parts, though I agree that there are a lot of "audiophile" caps out there that aren't really to my liking.

[AllanMarcus]

I finally got around to changing the caps from the dayton 10uF to the same quality dayton 20uF. To my old ears, the 20uF caps sounds slight darker. I did give them 10-20 hour burn in (FWIW). I wouldn't say better; only different. I think I prefer the 10uF, but the difference was very subtle to me, and might just be poor audio-memory. I just don't understand how people can listen to something, make a change that takes minutes, then listen, then hear very subtle differences. I can barely hear suite differences with A/B testing.

Well, back to listening to music and neurotically curating my music collection.

[Phippers]

Hi everyone,

I've just ordered some capacitors to try a little capacitor rolling of the stock 10uF Dayton output caps in my Mainline and I was thinking about how to do A/B comparisons between different capacitors.

Reading back through this topic, I see than in the past people have proposed switching the capacitors in situ, with strong feedback advising against.

I was wondering what people actually ended up doing?  Any advice?

Call me crazy, but this was my thought:

• Take a mono source and connect it to both L & R inputs.
  
  Externally to the Mainline, connect the stereo headphone output and wire it to the A and B side of a toggle switch, take the common out to both the L & R sides of a headphone socket.
  
  Now using the external A/B switch, one could listen to either the Left side or the Right side of the Mainline.
  
  Compare L & R with the stock Daytons - satisfy oneself that they sound more or less the same.
  
  Swap out a capacitor on one side only..... then one has an instant A/B comparison between the two caps, with no nasty DC volts being switched.

Granted, it would only allow a Mono comparison, but I'm thinking that it would provide instant comparison of tonality / bass extension / any audible effect of changing the capacitor value.

Thoughts anyone?