[yellowjeep]

 
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I am using cheap PSU I asked about earlier, this. I am also using this tube. 
 
I think the imbalance issue is in my head rather than in the amp. I have been listening to the amp on and off all night and I feel like its switch from the right to the left now. I was sick a few weeks ago and ever since I have felt like I hear better on the left, its weird and I think I am just paranoid.  
 
I am also having a terrible hum when the the source is unplugged. I am wondering if how I have the RCAs wired is a problem, I have them tied together and then one single wire running to the ground hole of the input on the PCB. 
Like I said earlier the hum all but goes away when I touch hold the PS jack or I just discovered if I touch the headphone jack, it might be that I am using wires that are way longer than ideal for the PS. I'm pretty much stumped  
 
Funny thing, I originally had the RCAs grounded to the extra hole for the PS and I was picking up NPR when the volume was turned all the way down.
 
 
I'd be happy to take those tubes off your hands just interested in trying others. I'm in KS. 
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[yellowjeep]

I am in the process of casing my amp up. I still have to drill a hole for a switch, I already drilled a huge one thinking I could get it large enough for my switch but no dice, so I am committed to my big switch. Lesson learned I suppose. I also need to find somebody with a stepped drill bit and a drill press to do the hole for the tube and possibly some vent holes. I am thinking about a craigslist ad with a 6 pack in return for 3-4 holes drilled. The rest of my case work is acceptable I suppose but I will do somethings differently next time. 
 
That said, I still have hum coming from somewhere. Most of it is gone after grounding the pot but there is still quite a bit when there is no source plugged in and even where there is there is still a low level hum that is independent of volume. 

 

[yellowjeep]

I think I have the hum issue solved. I am just waiting on a plastic DC jack and a stepped bit to finish this thing up.  I scored an Amperex Bugle Boy that sounds amazing but is slightly microphonic compared to the 6N23P which also seem over built. 

 

[ppklok]

Hi. Could someone share "the" BOM? As my pcb is still in post I don't want to wait another week for rest of the parts..
 
Btw which factory is your 6N23P from, yellowjeep ?

 

[yellowjeep]

The tube is from the Reflector factory according to the eBay auction.
 
There is no "the BOM" as far as I could tell. Here is a link to the original BOM Kansei put together. FWIW for my build I used most of the resistors listed in the BOM but substituted all of the caps and a few resistors in the audio path, the BOM is a good starting point but half the fun, for me anyway, getting to be really picky about what components I was using. For instance using a larger than specified cap for C103, there are tons of recommendations in this thread.  
 
Edit: C103 is the main power cap and the schematic calls for a 25v 1000uf electrolytic. I think its been universally agreed upon that 25v probably doesn't leave enough margin for error when using a 24v power supply. I personally used a 35v 6800uf Nichicon Muse and I know others have sometimes been using caps north of 10000uf . Food for thought.
 
Read though this thread for other substitute ideas. Some of the MOSFETs are hard to source. I replaced the 2SK310 with IRF510s from Radioshack. I'm done rambling. If you have any other questions I will try to help, I owe it to the community to pay it forward. 

 

[ppklok]

Great, Kansei's bom looks almost the same as what I have figured out from the photos. Is that correct that only R101/R201, R104/R204, R105/R205 and R109/R209 needs to be 1W, rest 1/4W.
 
I have a Panasonic EVJ volume pot which is only 50k so is possible to use it instead of 100k pot?
 
I agreed, the MOSFETs are quite hard to get especially if you don't want to order from many vendors. I think I will use IRF510s and 2N3819s.
 
For tube I went for Voskhod 6N23P because some people claim that it's "better" than Amperex PQ's. Even if it's only a opinion for under five bucks I think it's worth of trying.
 
Thanks.
 
 

 

[yellowjeep]

From what I've read the value of the pot determines two things, noise floor and how easy it is for your source to drive the amp. So the higher the value of the pot the the easier the amp is to drive but the trade off is that you also have a higher noise floor. In most of the threads I have read people seem to favor 50k pots a good compromise, I think you will be alright with the Panny.
 

 

[Pseudonyms]

Would this capacitor be suitable for use in the C101/C201 spot?
 
http://www.futurlec.com/Capacitors/C100UPF.shtml
 

 

[FallenAngel]

Yes, Wima MKS4 is quite nice.

 

[Pseudonyms]

Very cool. I'm almost done assembling my list.  The whole electrolytic capacitor business has got me in a jumble though. So many choices.  What are the spacings on them again?

 

[GT20v]

Quick question.....
 
is the fuse really needed here? is it ok if I omit it?

 

[yellowjeep]

You could but why? If you have a spike in power or you short something when adjusting bias you will fry transistors and all kinds of stuff rather than just a cheap fuse.

 

[GT20v]

well..it just that im using a regulator....unnecassary stuff in the signal path....i dont see a power spike as issue...
 

 

[yellowjeep]

Go for it then

 

[MrSlim]

Quote:

Quick question.....
 
is the fuse really needed here? is it ok if I omit it?

So, you are going to rely on the house circuit breaker that your amp is plugged into to protect you from an error in wiring in the amp from destroying expensive components in the amplifier. That means that 15 amps of current will be flowing through the mistake before the breaker trips.  That can do a lot of damage.
 
Unless I missed something, there are no fuses in the signal path in this design(no one does that anymore), they are strictly in the power supply.