My finished attempt - old computor case, homemade PCB - sounds very nice so very pleased 
- I built this and a SymaSym 5.3 as a beginners project, but was only able to do it by referring to the two threads on this forum, which have supplied me with all the technical support that I have needed. My thanks to Salas and everybody else whose expertise has been shared via this forum
- I built this and a SymaSym 5.3 as a beginners project, but was only able to do it by referring to the two threads on this forum, which have supplied me with all the technical support that I have needed. My thanks to Salas and everybody else whose expertise has been shared via this forumAttachments
Macronaut, the short answer is YES, there will be no problem by putting a lightspeed in front of the DCB1. I will do it as soon as I receive my LDRs. Photos will come.
Congratulations jandr49, you had the guts to etch your own PCB It has a clean wiring scheme too, and a nice sturdy front panel, very aesthetic
Regards,
Regi
Congratulations jandr49, you had the guts to etch your own PCB
It has a clean wiring scheme too, and a nice sturdy front panel, very aesthetic Regards,
Regi
DCB1 is great with LDRs and please.. this is no sales pitch.
I tried a lot of different resistances and if you would like to do the same you will find sonic differences.
I often say I liked 6k the best. It is where I settled and enjoy. However.. 600R, yes below 1k sounded phenomenal. It worried me that my CDP could not drive it for long so I upped to 6k and enjoyed that.
Inspect the specs of your source and find the output impedance. I dont know the max you should not go above as far as source output impedance but I think mine is below 50R and it will drive near anything. If you mess with these resistances in the Lightspeed it will be rewarding but be careful with your source to not over load it.
I wish I had more to contribute about not overloading.
Uriah
I tried a lot of different resistances and if you would like to do the same you will find sonic differences.
I often say I liked 6k the best. It is where I settled and enjoy. However.. 600R, yes below 1k sounded phenomenal. It worried me that my CDP could not drive it for long so I upped to 6k and enjoyed that.
Inspect the specs of your source and find the output impedance. I dont know the max you should not go above as far as source output impedance but I think mine is below 50R and it will drive near anything. If you mess with these resistances in the Lightspeed it will be rewarding but be careful with your source to not over load it.
I wish I had more to contribute about not overloading.
Uriah
I don't know why this has not spread like wildfire and explored further by B1/DCB1 builders...and it goes way back as suggested here post #320:
http://www.diyaudio.com/forums/pass-labs/76557-threshold-ns10-lineamp-pcb-32.html
and then here again:
http://www.diyaudio.com/forums/pass-labs/124889-b1-buffer-preamp-234.html#post2164071
http://www.diyaudio.com/forums/pass-labs/76557-threshold-ns10-lineamp-pcb-32.html
and then here again:
http://www.diyaudio.com/forums/pass-labs/124889-b1-buffer-preamp-234.html#post2164071
My local electric service is over the top, literally. The transformer sits at the corner of my yard. I have ~122 VAC. Along with this I am using a "25.2 VCT" transformer. It is pretty generous as well.
I have +/- 14.7 VAC rails going to this. I hoped to be able to "hot rod".
V across R1's are 1.462 & 1.502
The output relay clicks.
DC offset is .001/.003 V
Vout is 9.48 & -9.19
The mosfets are P140 & P9140. I do plan to heatsink them.
Hi Ed,
Did it work in the audio system OK in the end?
Hi! I have a request for the buyers of the Gigawork pot. Could you please let me know if you are still satisfied (in terms of sound and reliability) with your purchase now that you've had some time with it? I'd like to buy it for my dcb1 and I was wondering if it's indeed a better idea than something like this ALPS. Then there are some other stepped ones like this but they start to depart from the "peanuts price".
@DQ
You could try this R2R audio volume / input selection and images hete. Contact danzup for more information if you are interested. I've done this and I plan to use DCB1 as output buffer for it.
You could try this R2R audio volume / input selection and images hete. Contact danzup for more information if you are interested. I've done this and I plan to use DCB1 as output buffer for it.
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Greets Salas!
Not yet, I had forgotten the attenuator shown was set up as 10K a long time ago. So, I have udailey's LDRs and will be making an attempt to listen soon.
This is part of a system make-over. New speakers will be actively tri-amped.
Econowaves with 4x Scan S 25W/8565 subs
Leach 12X
AAK's SymAsym DTV (is working & recommended)
F5
I will bring it all together in the end.
Not yet, I had forgotten the attenuator shown was set up as 10K a long time ago. So, I have udailey's LDRs and will be making an attempt to listen soon.
This is part of a system make-over. New speakers will be actively tri-amped.
Econowaves with 4x Scan S 25W/8565 subs
Leach 12X
AAK's SymAsym DTV (is working & recommended)
F5
I will bring it all together in the end.
Be aware with fake Alps on Ebay. The original ones I have don't have these rounded solder terminals. They look like these ones:
http://www.kaponk.com/files/pot-alps-rk27-50ka-01.jpg
I bought an attenuator type switch from ebay. A vanilla one, without any resistor soldered. After some days of use, I realized that it gives bad contact in some middle position. It is a 10$ on on ebay too, I don't recommend anyone to get it.
Regards,
Regi
Greets Salas!
Not yet, I had forgotten the attenuator shown was set up as 10K a long time ago. So, I have udailey's LDRs and will be making an attempt to listen soon.
This is part of a system make-over. New speakers will be actively tri-amped.
Econowaves with 4x Scan S 25W/8565 subs
Leach 12X
AAK's SymAsym DTV (is working & recommended)
F5
I will bring it all together in the end.
Thanks for the info. Promising system...
10K pot is OK too for DCB1 if your sources don't mind.
Are you planning to place a pot between de dac and thr DCB1?
If not, I bet you will have no problems. Output impedance shall be low enought, and DCB1 input impedance is high enought.
If you plan to place a pot, depending of your dac's output impedance, you may have no problems. Do you know how much is it? With a 20k pot in front of the dcb1, there are not many devices that will cause a problem.
Resuming, yes we can :=)
If not, I bet you will have no problems. Output impedance shall be low enought, and DCB1 input impedance is high enought.
If you plan to place a pot, depending of your dac's output impedance, you may have no problems. Do you know how much is it? With a 20k pot in front of the dcb1, there are not many devices that will cause a problem.
Resuming, yes we can :=)