Small tid-bit on Electrolytic caps: They take approximately 24 hours under voltage to fully develop. During that time, they have substential leakage current (in the high uA range).
So either burn them in before installation of put them in and leave the device running without load over night.
They burnt in for a good 6 hours before I listened, and are continuing to burn-in as we speak. 
But Iāve heard stories of some electrolytic capacitors taking upwards of 100 hours of burn-in to fully develop. I know that polarization has some impact on burn-in length as well.
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PCC88ās are specād to run at heater voltages of 7.6V. The LP heater circuit provides 6.3V, thus the tube will run under-voltage and thus under its operating specs. From the SBAF post linked below: āPossible effects sonically are a little more tube compression, meaning a little warmer possibly a little more harmonic distortion often perceived as air and space.ā
It shouldnāt damage the tube or the amp though. It is just that you are not getting everything from the tube. Then again, you may enjoy the end results of this pairing. Cāest la vie.
Yup, im aware of the voltages. They do sound really good thoughā¦better than my Siemens 7308 or my Amperex PQ Gold Pin tubes, so that is high praise coming from me.
Very impressive. Can you get the socket savers easily?
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I ordered mine from ebay, but there are a few places you can buy them. They all are basically Bakelite branded 9 pin socket savers.
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10 bucks for 4 on Amazonā¦hmmmm
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I paid $4.00 for the 2 that I bought from an eBay seller.
Really sweet build hazi. Glad you made it into something you can enjoy 
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What are you using on the XLR output? Iām diving into this mod, cheap and relatively easy to do so why not?
Out of curiosity Iāve been using the Genalex Gold Lion tubes, been happy with them. Found them to be a noticeable step up from the Eletro Harmonix it came with. Nothing earth shattering but a little better in every way.
I might try the tube savers, sucker gets HOT!
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Are you referring to the capacitor or the cable?
The capā¦
I am using a 100 uf 25 V Elna Silmic II, 3 x 470uf 63 V Elna Silmic II caps (the 3 jumbo ones), and 2 x 10 uf 25 V Elna Silmic II caps next to one of the jumbo caps.
On the picture below, the 100uf 25 V capacitor is circled in Yellow, the 3 x 470 uf 63 V capacitors are circled in Blue, and the 2 x 10 uf 25 V capacitors are circled in green.
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Do those just insert into the existing socket or are the soldered to the PCB? I see a couple types and the ones that appear to just insert to the existing socket all look to be too tall. When I look at your photo it looks like the legs are soldered.
They are radial capacitors and are soldered to the PCB.
I was asking about the socket savers. I need to google better.
Oh, am I just a goof - those are the sockets, and the socket savers are not pictured?
The socket savers are inserted into the socket and the tubes into the socket savers. Below is an image that will give you an idea of what they look like. When I took the pictures of my installed caps, I didnāt have them in yet.
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Thanks, I figured it out after I looked through the vents.
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Impressions, okay here we goā¦ it either took the amp a bit to burn in or my head but either way itās been my experience that the mlp went from being a very mid forward amp to being a lot more balanced to my ears especially in the low end after quite a fews days of leaving it on for quite a few hours per day.
Iāve been listening to it pretty much exclusively with my lcd-2pfās (balanced in and out w/ bifrost 2) and no surprises here itās a very fine pairing as Iām sure many have said above. I finally feel like the 2pf is somewhere approaching its peak performance and certainly a significant upgrade from the asgard 3 (with these headphones specifically). Low end especially is more articulate and Iām getting much more information and impact. Iāve always loved the 2pfās for drums and bass guitar and now itās like giving it a level up on this amp.
Guitar distortion sounds amazing. Itās really detailed and gritty but itās not elevated so thereās a nice balance going on there. Nice timbre throughout which is something I feel like the 2pf excels at and the mlp just lets that goodness come through. Itās just a great chain that allows more aggressive music to be really listenable and enjoyable.
After listening to the stock tubes for quite awhile I switched to Siemens O-Getter Gold Pins. I have not spent too much time with these yet but my thinking so far is they are pretty great. Smooths out the presentation just enough to be even better without losing information. Canāt say much really as itās a much more subtle difference than tube rolling a bottlehead crack for example. Might be getting slightly better spatial recreation but I canāt confirm if thatās my brain wanting that from the tubes or if Iām actually getting it.
Anyways, hope I didnāt rehash too many things as I havenāt read through this thread too much.
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I donāt think you did, and even so, I spend a lot of time reading through and re-reading here in the forums trying to get as much information I can and learn what otherās experiences are - from their POV. So, I am glad you put your thoughts out there. Especially when it is gear I have myself or am considering. I am now off on another tangent wondering what Audeze HPās might pair up with the mlpā¦ Iām sort of like that dog in the Kids movie āUpā Squirrelā¦
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