Thanks Amit, none of the wooden face plates are polished yet. I have pearl-2 + PS too pending. I plan to do some letter engraving before final polish. That is just changing boxes to new one's and then I will take out one single round for polishing.
Pass B1
- Thread starter sachu888
- Start date
Thanks, I did not use it. I will add it later from mains earth ground to chassis. Now kept ground isolated as B1 '0' line ground is already connected in chassis.
One of the remedy is to use LDR based volume control, its smoothness is hard to describe, its a completely different experience of controlling the volume through LDR, and thats what I was using when I built my Pass B1, however I shifted to 50K log pot after a few months, the reason was compromised low frequencies with B1 + LDR.
Though I already knew the capabilities of buffering the LDR with another B1 (my observations of it can be referred in post#830 here)
at the front and acquired the another B1 kit with the intentions of building the double decker, however the 50K pot resolved the low frequency issue, so I put it on the back burner for more than a year, until recently FM svaze called up and shouted - hide the LDR behind a B1 san', svaze talks less, but talks absolute sense that was enough for me to pull out my kit and switch the rod hot.
This also disintegrated the B1 from the Norge Preamp (described here)
Here it is:
Thanks Raghu for this beautiful cabinet
My Impressions: After cursing myself for not putting it together early, I dropped the needle and sat down, first thing - bass and more bass, are they the same old speakers? Yes absolutely. Clean and dark background even at high volumes which was completely missing with the 50K log pot is back again. Resolving more music, and interestingly, the channel separations has increased (dont know the reason of it though).
Special thanks to Om for first experimenting and sharing the 'Double Decker' concept with us.
~Happy Listening~
-sann'
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sachu888
Well-Known Member
I need to experiment this. Sandeep what happened to your volume knob?
Regards
Sachin
Regards
Sachin
I got few inquiries about connecting B1 before Volume control. If you build B1 as per standard procedure then it provides buffer after volume pot. But I have put it one more which comes before Volume Pot. Please see below snap where circled area is where signal wires from source selector can land. I connected all these at 'W' (signal live/hot) and 'CCW' (ground) pads.
I rewired all signal wires as below -
Some more pics on letter engraving, waiting for nice feet for these cabinets.
I rewired all signal wires as below -
Some more pics on letter engraving, waiting for nice feet for these cabinets.
sachu888
Well-Known Member
Excellent:clapping:
Regards,
Sachin
Regards,
Sachin
I did not mount power caps on this extra B1 which I shown here. I just jumped three wires 2 from each power capacitors +ve and one from common ground to upper B1. That's all.
So this is what I am repeating from my earlier message:
About double B1 is inside [] below -
It's "Source -->(1M?) [B1 without volume control -->second B1 with volume control](50?)--> power amp"
We short volume control Position in first B1, 'W' and 'CW' pins making is pass through signal directly. I used to use one input and output from each so I shorted toggle switch in used input pads.
Technical side is - This first B1 hides volume control from source, and source feels preamps input impedance as 1 M? which is B1's and very large and any source works without loading or ill effect. Again second B1 as usual shows output impedance of 50? which can drive any power amp. So you get good impedance translation. And no distortion.
As said above (and I once posted much before the single B1 group buy was even executed ) the lightspeed shows very low Input impedance to the source device so it will struggle to deliver power to the B1 without double sandwich of B1s with the LS in between.
HTH
-G0bble
Yes! In fact any buffer before volume control made difference. First I tried SSP (with AD823 opamp). That was success but it was influenced by OPAMP. Then I tried B1 in place of SSP and yes, its neutral. I always prefer this.
It makes notes, BASS tight and accurate. Also instrument separation is huge.
Again in second B1 with me, I tried SSP without its output caps but with LME49990 chips. It made me smile as I was liking the sound as lively but definitely not neutral. Changed input-output 1K? resistance in pass B1 to 220?. This makes sound-stage wide and one could feel change in low end.
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Is there any truth to the assertion by some folks that using the LDR brings the sound forward? I am looking for a laidback kind of sound. Am I better off with a regular volume pot?
Believe me, regular pot looses much of resolution. Instead use resistor ladder volume control with DALE VISHAY resistances. Its my second choice after LSA as it has great L-R matching. Pot must be passing all SQ to output. But wiper mechanism influences highly.
YOu didnt answer Jai's question - is it forward? I used the same pot that I saw in a pic of your DIY in my GG clone. Did you get yours from HK?
I was very happy with the sound of that ladder v.c, except that one or two resistors started getting scratchy within two years of use.
-G0bble
YOu didnt answer Jai's question - is it forward? I used the same pot that I saw in a pic of your DIY in my GG clone. Did you get yours from HK?
I was very happy with the sound of that ladder v.c, except that one or two resistors started getting scratchy within two years of use.
-G0bble
No I don't feel it's forward.
My ladder volume control is from some Australian site. Contact switch is gold plated, premium. I am using since 6-7 years. No problem so far. But I remember I paid almost rs2500/- for that.
I did not understand how it won't need light speed kind of pot. May be I missed something while reading? Can you please point out?
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