Nelson Pass B-1 preamp kit

parodielin · « **Reply #240 on:** 25 Apr 2010, 04:21 am »

Quote from: avionic on 25 Apr 2010, 04:08 am

Let me see if I can find the place and then post a link. I have a hard time finding it on my home computer but it pops right up at work. Different search engine I guess.
Found it http://www.onlinemetalstore.com/

Glad to know such store exists. Do you need to order six sheets and put them together as a box?

parodielin · « **Reply #241 on:** 4 May 2010, 03:21 am »

So I used a Hammond Chassis. Magically - all noise are gone and the match with Class D is like heaven. The combination clearly trump my old HK 635. Wow - I never thought a preamp would make such a big difference. The noise almost killed my confidence. Hey the simple metal box and proper grounding solve all previous issues. It's dead silent, crystal clear and the image is huge.

Thanks wushuliu for suggesting such a nice preamp. Love it!!!

wushuliu · « **Reply #242 on:** 4 May 2010, 04:25 am »

Quote from: parodielin on 4 May 2010, 03:21 am

So I used a Hammond Chassis. Magically - all noise are gone and the match with Class D is like heaven. The combination clearly trump my old HK 635. Wow - I never thought a preamp would make such a big difference. The noise almost killed my confidence. Hey the simple metal box and proper grounding solve all previous issues. It's dead silent, crystal clear and the image is huge.

Thanks wushuliu for suggesting such a nice preamp. Love it!!!

parodielin · « **Reply #243 on:** 4 May 2010, 04:47 am »

Really, I am very very impressed of the combination of B1 and Class D. Unbelievable... I have client work tomorrow and I am still listening to the music.

Now tell me what to upgrade on DAC!!!

Quote from: wushuliu on 4 May 2010, 04:25 am

walkern · « **Reply #244 on:** 4 May 2010, 03:41 pm »

VERY encouraging! I've been trying to combine the China based Pass board with a Class D amp in the same chassis for a while now with no luck. One channel of the China board won't work, and the one channel that does kept giving me hum issues... so I've finally given up on the combo and have ordered a real Pass board, all the necessary parts, and a dedicated chassis. Glad to hear that this combo is a winner. In the mean time, I am enjoying the Class D amp, which IMHO is a genuine bargain and an awesome performer.

Neil

avionic · « **Reply #245 on:** 4 May 2010, 04:55 pm »

I spent the $15.00 to buy 2 sets of 9volt batts and the terminals from radio shack just to try the pass b1 on battery power. It is more clean and clear than run off the small plug in power supply.
I have been listening for 3 days now on the same batteries. Very impressive for the small investment.

1MOR · « **Reply #246 on:** 10 May 2010, 02:53 am »

N.P. states that "...D2 is a generic LED for indicating power...". I see that LEDs are available with different voltage ratings. Does N.P. indicate that any LED would be appropriate for use? I have a few blue LEDs rated for 24 volts. Would those work in the B1?

1MOR · « **Reply #247 on:** 11 May 2010, 11:17 pm »

So no one used a LED?

wushuliu · « **Reply #248 on:** 11 May 2010, 11:23 pm »

Quote from: 1MOR on 11 May 2010, 11:17 pm

So no one used a LED?

Your 24v LEDs will be fine...

1MOR · « **Reply #249 on:** 12 May 2010, 01:53 am »

Thanks wushuliu!

Pass boards and chips are here, Obligato caps are somewhere between HK and here, I hope, and Digikey has shipped. Hope to get started soon!

HAL · « **Reply #250 on:** 16 May 2010, 02:48 pm »

Ok, today is B1 solder day. Need to go to RS and get the input channel selector switch. The 100K Alps Blue Velvet pot is here, but need a chassis at some point.

Just ordered a pair of Li Ion rechargable 9V batteries and matching battery charger. They should last 20-30 hours on a charge and should be good for 700 charges. That should be good for awhile.

wushuliu · « **Reply #251 on:** 16 May 2010, 05:42 pm »

Quote from: HAL on 16 May 2010, 02:48 pm

Ok, today is B1 solder day. Need to go to RS and get the input channel selector switch. The 100K Alps Blue Velvet pot is here, but need a chassis at some point.

Just ordered a pair of Li Ion rechargable 9V batteries and matching battery charger. They should last 20-30 hours on a charge and should be good for 700 charges. That should be good for awhile.

keep us posted and post pics when yer done!

HAL · « **Reply #252 on:** 17 May 2010, 08:10 pm »

Here are the pictures of the Pass DIY B1 Buffer kit in an old DIY preamp chassis that I had available.

The batteries are Li Ion Rechargeables. Charging them now for use this evening!

grubyhalo · « **Reply #253 on:** 18 May 2010, 07:07 am »

Neat!

HAL · « **Reply #254 on:** 18 May 2010, 12:51 pm »

Thanks!

Have to swap the volume pot leads on the left channel. I wired it backwards and have a great balance control instead of a volume control. DOH!

Will rewire it today and have some fun.

HAL · « **Reply #255 on:** 18 May 2010, 02:08 pm »

Ok, the B1 is rewired and sounding very good!

The setup is my Gateway MP8708 laptop with Foobar 2000 driving a Musiland Monitor 01 Mini 24bit/192KHz Asynchronous DAC via kernel streaming mode and the HDCD DSP plug-in. This drives the B1, which drives an AV123 X-Head HPA for my Sennheiser HD-650 phones.

This is my favorite way to check out equipment as you hear any noise or distortion easily over phone.

Music is the Reference Recordings HRx 24bit/176.4KHz of Exotic Dances. This is a very nice recording!

Frequency response and dynamic range are outstanding with this setup. I like what I am hearing so far and will give it some time for burn-in. Then off to the ssytem.

jtwrace · « **Reply #256 on:** 18 May 2010, 02:09 pm »

HAL

You're building one of these as well? I'll look forward to your comparison between this and the other buffer.

HAL · « **Reply #257 on:** 18 May 2010, 02:18 pm »

I have had the B1 kit for about 2 years and wanted something until the Dodd battery buffer arrives and is built. My Dodd battery preamp has to much gain for the setup so a buffer is a very good way to go.

Tonight will be the battery DAC driving the battery B1 driving the battery PA for the Super-V's! This should be interesting!

wushuliu · « **Reply #258 on:** 19 May 2010, 12:56 am »

Quote from: HAL on 18 May 2010, 02:18 pm

I have had the B1 kit for about 2 years and wanted something until the Dodd battery buffer arrives and is built. My Dodd battery preamp has to much gain for the setup so a buffer is a very good way to go.

Tonight will be the battery DAC driving the battery B1 driving the battery PA for the Super-V's! This should be interesting!

Do you have a wall wart to compare battery B1 vs. regular? I think I may test that out tonight.

And for the record, if I have to read another 100+ page thread on diyaudio just to build a project my brain will explode. After 2 years I am DONE.

Lyndon · « **Reply #259 on:** 19 May 2010, 01:28 am »

Wushuliu said:

Quote

And for the record, if I have to read another 100+ page thread on diyaudio just to build a project my brain will explode. After 2 years I am DONE.

I hear ya! I am waiting, waiting, waiting for those Pearl 2 boards to drop. Gots' to have my Pass Phono!
Lyndon