[I.Greyhound Fan]

Have you tried the Obilgato's in the past and thought the bass was lacking? 
I tried the B1  board with old 10yr old slagle/intact audio autoformers  (AVC) and couldn't get enough bass from it. Maybe my stacking of the cores wasn't right but I could never get deep bass  from it in the past

I am just going by the reviews of the Obbligato's.  I realize that it's all subjective and it will depend upon what electronic's you mix them with.  I may end up swapping my Clarity ESA's for them in the long run.  I should have my build done in about 2-3 weeks.

How many hours do you have on the preamp?  The caps definitely need time to burn in.  I had a friend replace all the Jensen PIO caps in my BAT preamp and it took about 20hrs for them to sound good and about another 100hrs for them settle in.

http://singaporehifi.blogspot.com/2010/09/capacitor-shoot-out.html


"Obbligato Gold Premium Cap

Initial impressions during burn in time were quite promising. A very even handed performer with a neutral balance and good detail throughout. Balance wise, this reminds me of the Auricap the most except that the Obbligato has more extended and wetter highs. Midrange is pleasingly smooth without being muffled and there is plenty of information being conveyed in a tidy and controlled fashion. The Achilles' heel of this cap is its bass which is slightly rounded and not particularly deep, especially compared to the Mundorf Supreme series. This results in a somewhat lighweight sounding presentation. That being said, this is a very good cap, especially considering its competitive price. Subjectively, I feel that except for the bass issue, the Obbligato is more pleasing than the Auricap at a much cheaper price."

[I.Greyhound Fan]

I completed my B1 build a couple of weeks ago.  My jaw dropped when I first heard it.  It is stunningly good.  Bass is deep, powerful and controlled.  There is just a little bit of bloom which I like.  The sound stage is wide, airy and transparent.  The mid range is where it really shines.  It has very good depth with a lot of texture and a nice smooth yet detailed sound.  If I had to pick a weakness, it is the highs which are slightly pushed back and rolled off a bit on certain recordings.  Otherwise cymbals have good timbre.  Vocals, horns and piano are stunningly life like with a rich harmonic texture and musicality.  It has good attack and just a slightly forward mid range. The overall sound is just slightly warm and dark which was by design with the caps and resistors that I picked.  I built this for my son to use with my old Parasound A21 amp.  I did try it in my reference system with my Pass X250 amp and Maggie 1.6 speakers.  It did not sound as good as my BAT preamp but it certainly was not embarrassed.  Not bad for $300 worth of parts.  Next up is to get a remote volume pot and board and then add a real power supply instead of the walwart.

I will post pictures later today.

[Folsom]

Don't use a Pot mate. They're not going to impress you. Instead of use an eBay chinese DACT, and then add a remote control for it if you must have remote. Switching from a pot to one of those is close to the difference your B-1 made in my experience.

[I.Greyhound Fan]

Don't use a Pot mate. They're not going to impress you. Instead of use an eBay chinese DACT, and then add a remote control for it if you must have remote. Switching from a pot to one of those is close to the difference your B-1 made in my experience.

Thanks for the tip.  Do you know of any DACT type with a remote kit for $100 or less?   $100 is the budget.  Currently I am using an Alps Blue pot 50k.  I was considering one of these Kits with either a TKD or Blue Alps pot.  I don't know if the TKD will be any better than the Alps

http://www.hificollective.co.uk/catalog/potentiometer/tkd-2cp-2511-motorised.html

[Folsom]

I do not. Perhaps you could link one to a motorized device? I'm not sure what would occur with the stepped part, but they are make before break so it's safe to try.

[I.Greyhound Fan]

Here are pics of my B1-













I am going to add a Remote TKD volume pot and board along with a Torroidal power transfomer

[yardbird]

Hey guys,
Newbie question. Am building the buffer and got a "Pass" small enclosure off of Ebay. It came with an AC in and an AC switch. I am going to use batteries or a wall wart to power the buffer. Can I use the AC power switch to turn off the power and eliminate a drain on the batteries? The Negative lead will still be "active" to the buffer. Will this hurt the buffer? Seems like I need a switch that will disconnect the positive and negative leads??? Any suggestions?
Thanks,
 Jeff

[yardbird]

Never mind. Saw in the build pics where a switch was included with batteries. Seems to work fine. I used Sonicaps with a gen 2 bypass, naked Vishay 320k in the 4 critical positions. I had to order 2 shorter Rubycon power caps to allow it to fit in the case I bought. Powering it with batteries. Sounds really nice with no break in. A substantial improvement in my system (Wadia 121 dac, Prima Luna Prologue 4 and Dennis Murphy designed ER-18s). Very happy. I'll try to post a pic. Now, can I build the F6 without killing myself?

[Coup36]

Hello DIYer's,

Wanted to say thank you to everyone that has contributed to this thread!  I just finished my very first DIY build which was a ton of fun but would have been impossible without this thread as a resource.  Check out the finished product below. 

Pass B-1 Dual Mono Integrated Amp:
 - Pass B-1 Buffer (BOM as listed by wushuliu) 
       - Mundorf MCap EVO 10uf
       - Jantzen Superior ZCap MKP 1uf
 - IcePower 50asx2 - mono X2
 - 25k Apls Pot
 - Velleman K1823 1A power supply
 - AnTek AN-0118 10VA Transformer
 - Aluminum amp enclosure WA11 (eBay)

[I.Greyhound Fan]

We just replaced  (with the help of a friend) the manual Alps Blue volume pot with a remote controlled TKD from Hi Fi Collective and the sound is noticeably better with greater clarity, air and detail.  Textures are improved as well.

[KR500]

just purchased the legitimate B-1 Board with matched jfets from Nelson Pass via the store and printed out the BOM from the first page
I am thinking about upgradeing  the resistors and caps, but after looking at the price of 4 Vishay tx 2575 resistors my fixed income budget got sticker shock.
At the bottom of the BOM post on page 1 it mentions PRP resistors. for the thrifty audio fan , but the link to the retailer is changed and I couldn't find resistors marked PRP at the new site . Are these for the 4 1K input resistors people suggest upgrading ?   I realize this is an older thread .
I posted here because the other one is huge in length.
Are the suggested bypass Dayton film/foil caps paralleled to get 1uF  suggested upgrades for the metallized polypropelene caps in the digi-key BOM ?
I use a couple of tube integrated amps, one a Class A and the other AB  along with some AB solid state amps . Does the B-1 work well with tube amps ?
thanks

[wushuliu]

just purchased the legitimate B-1 Board with matched jfets from Nelson Pass via the store and printed out the BOM from the first page
I am thinking about upgradeing  the resistors and caps, but after looking at the price of 4 Vishay tx 2575 resistors my fixed income budget got sticker shock.
At the bottom of the BOM post on page 1 it mentions PRP resistors. for the thrifty audio fan , but the link to the retailer is changed and I couldn't find resistors marked PRP at the new site . Are these for the 4 1K input resistors people suggest upgrading ?   I realize this is an older thread .
I posted here because the other one is huge in length.
Are the suggested bypass Dayton film/foil caps paralleled to get 1uF  suggested upgrades for the metallized polypropelene caps in the digi-key BOM ?
I use a couple of tube integrated amps, one a Class A and the other AB  along with some AB solid state amps . Does the B-1 work well with tube amps ?
thanks

You can get PRP resistors from Sonicraft (who also have a circle here). They also have Takman metal film and carbon film resistors that are also very good.
yes the film/foil caps are an upgrade, but this is very subjective. I'd once again point to Sonicraft and their Sonicaps I and II as possible upgrade caps.
The B-1 should work with whatever amp you pair it with.

[wushuliu]

Hello DIYer's,

Wanted to say thank you to everyone that has contributed to this thread!  I just finished my very first DIY build which was a ton of fun but would have been impossible without this thread as a resource.  Check out the finished product below. 

Pass B-1 Dual Mono Integrated Amp:
 - Pass B-1 Buffer (BOM as listed by wushuliu) 
       - Mundorf MCap EVO 10uf
       - Jantzen Superior ZCap MKP 1uf
 - IcePower 50asx2 - mono X2
 - 25k Apls Pot
 - Velleman K1823 1A power supply
 - AnTek AN-0118 10VA Transformer
 - Aluminum amp enclosure WA11 (eBay)

Nice!

[KR500]

thanks for the post Wush, heading over to SC right now

[Steve]

We just replaced  (with the help of a friend) the manual Alps Blue volume pot with a remote controlled TKD from Hi Fi Collective and the sound is noticeably better with greater clarity, air and detail.  Textures are improved as well.

Yep, agree I.Greyound. I tested and used a 25mm TKD pot in my last few preamps and  it was unbelievably natural and accurate. That and Noble (not manufacturered anymore) were the best I have ever tested for accuracy and naturalness in every aspect of reproduction. And of course smoothness of rotation is a good thing.

I think you can now concentrate on other aspects, tweaks that you may be concerned with.

Cheers and all the best.
Steve

[KR500]

I'm ordering from Parts Express per Wush's BOM ( thank you for posting that ) and wondered if the Jantzen Z or Solen 10uF caps are any improvement over the recommended one ?
Will try the Jantzen Z caps

(2) 10uf PP Cap

http://www.parts-express.com/pe/pshowdetl.cfm?PartNumber=027-932&DID=7

[KR500]

I got the four .47uf Dayton bypass caps to parallel in pairs per page 1's suggestion and only one caps lead will fit through the pcb . They are bigger than the area for them on the PCB.
If I solder the leads from one cap to the other cap mounted on the board it's going to be pretty top heavy..... so I was thinking about mounting the cap off to the side of the board ?
Looking at the previous pages of this topic I see a couple of other folks did this on their project with larger caps so I'm glad they posted pictures .A shrink wrap on the cap leads to insulate any bare wire from touching something on the board .
The 10uF Jantzen Z cap is pretty big too, so I may move that off the board mounting also.

Do you ground the PCB to the chassis ?
Should the input jacks be insulated from the chassis, or the ground tabs on the jacks to another point ?

thanks

[I.Greyhound Fan]

I used the insulating spacers with my RCA jacks.  We also used a star ground to the metal chassis.

[KR500]

thanks greyhound
On my amp project I grounded the earth center pin to the chassis.
The Pass B1 uses a wall wart jack with only positive and earth on the jack pin and outer shell,
I don't know if you use the negative pin of the jack as earth, and chassis ground , or something different ?

[KR500]

I don't need a volume control so will just put a resistor on each input as mentioned in an earlier post
Will any brand/type resistor work or is one type preferred for this use ?
thanks