Output Capacitor Upgrading Questions

[Laudanum]

Yeah, I should probably pick up some of the affordable, smaller value russian teflons that show up on ebay all the time.  That way I'll have them.  Ive never used a teflon cap before.  Forget the big brand name teflons, too expensive for me.  But I suppose it would be worth trying some of those russian cheapies.  What about polystyrene for bypass?  I assume they arent a great choice since I havent read much about them.  But I think I may have some from a couple lots I picked up really cheap on ebay years ago that I figured would work as guitar tone caps.  I think that they were advertised as polystyrene anyway, if memory serves.  They may just be mylars but they indeed make for pretty nice tone caps in guitars.  I have 2 or 3 different lower values but not sure of voltage rating or particulars.    I'll dig them out and see what they are exactly if the experts here think a polystyrene bypass is worth a listen.

[Laudanum]

I may have a line on a couple of 150uf solens (used/upgraded).  Would there be any reason to change the stock resistors at the headphone jack with lower value resistors?  I know it was suggested by Paul B to do so if going to a 330uf cap.  Just wondering if it would be considered necessary or a good idea if jumping to a 150uf and if so, what value would be suggested?

Thanks

[dubiousmike]

I finally dropped my Axon 91uF caps in last week - after spending quite a bit of time with the stock crack (except for a tkd pot), and then the speedball upgrade.  I would say the Axon's improve on the stock output caps, but the improvement is pretty subtle.  I would characterize the sound as being the tiniest bit more lush, and overall, a little smoother than before - but without any perceptible loss in detail.  This makes me really curious what, if any, difference I would perceive if I had a chance to try out some obbligatos or mundorf mkp's.

[Laudanum]

I have two of the Mundorf MKP 100uF 250V on the way.   I havent been all that impessed by the usual suspects ... the lower cost MKP's in other applications in the past, both electronic and speaker crossover.  I seriously considered the 91uF Axon regardless however as PC has them cheap.  Also considered the 100uF Erse as they are also inexpensive relative to most other MKP types in large values.  But I just didnt want to go down and already traveled road with the Axon or take a chance on the Erse.  Just seemed like the Mundorf was generally viewed as just a small step above the usual suspects and aside from the Axon through PC or the Erse, they arent all that much more money than the others.   I was hesistant to spend the money here because the amp sounds fantastic stock.  Speedball was probably the best bet, money wise.  But speedball is on the to do soon list. 
Im not expecting a big difference with the Mundorf.  Im hoping that they are a neutral sounding cap, with maybe a bit smoother upper mids and treble and a hair more detailed than the stock cap.  I suspect that it will be fairly subtle.  I have some Blackgate 150uF vk's in the parts bin, leftovers from old project.  I was going to try those at the output and still may if the Mundorf is a loser.  But jrebman gave me the idea of using these in parallel replacing the last PS cap.  I probably will do so of it's not too much trouble.
I'll report on the Mundorf's in the not too distant future. 

[Grainger49]

I am a confessed capacitor junkie, not in a 12 step program yet.  But the Speedball will bring you more in changes than tubes and capacitors.  So it might be the first upgrade.  Then...

After tubes and capacitor changes there are cables and speaker wires, tube sockets, resistors... the list goes on.  It can become a neurosis or a joy. 

But you will get an improvement over the stock caps.  As you say expect better, clearer, cleaner highs and improved presence and detail in the midrange.  It has been my experience that the better the cap the longer the break in period.  So there will be some time you will want to go back to the stock caps, persevere! 

[dubiousmike]

Laudanum - with respect to the order of your upgrades and ease of installation, you may want to consider putting your speedball in first.  It is going to be harder to angle your iron and gain access the various necessary terminals for the speedball once your large film output caps are in place (unless you plan to simply remove and then reinstall them at the time).  Per the advice I got from Beefy a while back (which worked well for me), it is probably easiest to put in fly leads and mounts for the output caps before installing the speedball, then do the speedball, then solder in and zip-tie down your new caps at the end.

Setting the above aside, I'll be eager to see your comments on your mundorfs whenever you get them isntalled!  Are these the ones you ordered in 100uf/250 http://www.partsconnexion.com/capacitor_film_mundorf_mkp.html ?

[Beefy]

Per the advice I got from Beefy a while back (which worked well for me), it is probably easiest to put in fly leads and mounts for the output caps before installing the speedball, then do the speedball, then solder in and zip-tie down your new caps at the end.

Yep, and I absolutely stand by that advice. My original build post on Head-Fi for reference: https://www.head-fi.org/forum/thread/476650/crack-bottlehead-otl/435#post_7149721

I am a confessed capacitor junkie, not in a 12 step program yet.  But the Speedball will bring you more in changes than tubes and capacitors.  So it might be the first upgrade.  Then...

After tubes and capacitor changes there are cables and speaker wires, tube sockets, resistors... the list goes on.  It can become a neurosis or a joy.

Yep, I would agree that Speedball certainly made a bigger change than the output caps, but even the 'lowly' Axons were still a good improvement over the stock electrolytics.

Aside from those two upgrades, I would put a better pot on top of the list - well above the other upgrade options you mention. The TKD I used in my Crack is gorgeous compared to the Alps blue in another one of my amps. IMHO, YMMV, $0.02 and all that......

[Laudanum]

Yep, I know that Speedball should be first but I never do things the easy or logical way anyway.   I plan on purchasing Speedball soon.  But I will probably install the Mundorfs first.  I'll secure them with self adhesive tie wrap hold downs, atleast temporarily. And solder them in so they are easy to remove for Speedball.  Im not very good at understanding circuits or schematics but Im pretty decent with a soldering iron so I have no worries regarding removing the film caps and desoldering and resoldering anything else that may make Speedball installation easier.    

Ive been down the upgrade path several times before but Im not an extremist.  I know that the caps can take a while to break in.  Teflon sockets and expensive cables wont be in the future.  Although I do probably need to make some different cables eventually.  I used Star Quad as I had some already and it was the easiest to use for the source (mini plug to RCA's) but the capacitance is pretty high with the Quad.  Although with the short runs, it probably isnt going to matter.  But Mogami or Canare is good enough for me.  I'll get around to the cables sometime down the road.  Also, headphone cable upgrades wont happen either and neither will internal wiring upgrades, atleast not with boutique wire or cable anyway.  
Speedball, the Alps Blue pot and the Caps and I'll have about the price of the stock Amp, or maybe a few bucks more, in upgrades when it's all said and done.  Still a steal of a headphone amp at 400 bucks all told.  

hopeful ... yep those are the caps.  I wonder how much it costs Mundorf to have them things made?  5 bucks a pop maybe ...   You can get a glimpse of the retail mark-up just by seeing how much less PC charges for the Axons compared to some other sellers.  I bet the Mundorfs dont cost any more than the Erse, Solen, Axon, Dayton etc. to make and if they do it's not much.  But in the audio world, 45 bucks isnt all that much for a 100uf 250V film cap.  


Good input, thanks guys.

[Laudanum]

Arent the TKD pots conductive plastic?   I may be a skeptic, but I just cant bring myself to spend gobs of money on a pot.  In fact, I would loved to just use the included alpha pot but the tracking at low volumes is generally poor.  I have several of those alpha pots and they are all over the place from sample to sample.  The Alps blue velvet tracks very well throughout it's range and is smooth.  I know that there are several popular pots that are supposed to be better and sound better, the TKD's being one of them often mentioned, but I just cant bring myself to spend much more than what the Alps cost.  And again, I am skeptical that two different conductive plastic pots is going to sound much different. But then again, I havent spent the money to find out what I may be missing.

[Doc B.]

PECs are nice pots for the money.

[Grainger49]

The last blue Alps pot I saw was stepped.  Upon opening it, it was a stepped resistor ladder.  My Alps Black Beauty isn't.  I don't know that a conductive film is a bad thing.  

Edit: I think the blue Alps I looked at were Paully's pots, Alps volume and balance, that we put in a Foreplay.

[Beefy]

I may be a skeptic, but I just cant bring myself to spend gobs of money on a pot.

The entire input signal passes through the pot before it even touches any other active component in the amp. I cannot think of a more important place to spend money. And I can assure you that they track better and sound better than an Alps Blue.

Arent the TKD pots conductive plastic?

Yes. Is that a problem?

[Laudanum]

Grainger, the Alps blue pots I have are conductive plastic.

Beefy, why would the conductive plastic pot be a problem for me, Im using one with the Alps blue?  
I know the signal passes through the pot.  It also passes through the wire from the RCA's to the pot and the wires after the pot, and  passive components in the signal path and ... etc. etc.   It can be an endless purging of the wallet.  Some of us have to stop somewhere.  As far as the pot goes, I DO NOT doubt that YOU can hear a difference in favor of the TKD.  I remain skeptical that I would be able to hear a difference whether it's the fault of my non-golden ears or the source or the headphones/speakers or a combination of all of them.  But whether I would be able to or not, it would to have to remain a case of ignorance is bliss for me, once again, because of that wallet thing even if I did have the burning desire to find out for myself.   Im sorry, it's not a religion for me but I understand that it is for some others and I understand that it is defended with a passion for those in which it is akin to a religion.  I dont begrudge anyone for that.  

[Doc B.]

Go easy guys, we're just talking about a volume knob here. To each his own.

[Billyk]

PECs are nice pots for the money.

I agree, they are at a good price point, value ratio for me. I think it was a nice upgrade over stock.
I still have to get my act together and install the Erse caps... Just to busy enjoying!