Have just tried the lightspeed in dcb1. Earlier in my AN linestage I tried
Alps Blue -> noble pot -> tkd cp2511 (all 100k dual logs)
The TKD was best, then noble and so alps blue.
The ldr volume control was much better than these (with regards to soundquality) but the volume tracking with the AN preamp was a bitch. Just perfect with the dcb1.
Alps Blue -> noble pot -> tkd cp2511 (all 100k dual logs)
The TKD was best, then noble and so alps blue.
The ldr volume control was much better than these (with regards to soundquality) but the volume tracking with the AN preamp was a bitch. Just perfect with the dcb1.
Correct, it is better than all possible B1 combos that I played with.
That said I'm yet to test it with pots (no mono pot below 20k with me right now)
While the optivol is inspired by and similar to the Lightspeed, it is NOT the Lightspeed. The LSA is minimalist/passive design without buffer. The power supply is only there to supply the LEDs, which are not in the signal chain. The optivol has a buffer, so you are listening to that as well.
In my system, the (passive) LSA lacked drive and volume and the highs were missing, even with 1.5M ultra low capacitance cables. However, the LSA is so highly regarded elsewhere in DIYA that I want to stick with it. Hence, I will add the DCB1 buffer, which I am confident is better than the optivol's buffer.
There are 5 commercial variations of the second generation Lightspeed that I know of. George (inventor) will say that all 4 clones are inferior to his.
In my system, the (passive) LSA lacked drive and volume and the highs were missing, even with 1.5M ultra low capacitance cables. However, the LSA is so highly regarded elsewhere in DIYA that I want to stick with it. Hence, I will add the DCB1 buffer, which I am confident is better than the optivol's buffer.
There are 5 commercial variations of the second generation Lightspeed that I know of. George (inventor) will say that all 4 clones are inferior to his.
sad news here
It's been a month since my dcb1 was finally housed in an appropriate box. When I passed to change the track today, I've inhaled a light warm smell of plastic coming from inside the box. After opening it, I found a tripplet of mosFET Vgs setting leds down. It's on a positive rail with a heatsink running blimey hot. Does that mean one of my Mosfets are down? Curiously, the music was still playing and the voltages measured OK.
It's been a month since my dcb1 was finally housed in an appropriate box. When I passed to change the track today, I've inhaled a light warm smell of plastic coming from inside the box. After opening it, I found a tripplet of mosFET Vgs setting leds down. It's on a positive rail with a heatsink running blimey hot. Does that mean one of my Mosfets are down? Curiously, the music was still playing and the voltages measured OK.
Check the leds first by trying to light them up one by one fast with a 9V battery as they sit there with the power down. If they all light up, then it should be the CCS Mosfet or the setting resistor.
Well I have a question
I have a 50va 15-0-15 rcore
Using a 10r mosfet source resistor gives 1.2 odd volts across the resistor.
This translates to 120mA,where did the rest go?
Again paralleling 2 10r gives 1 V across the resistor, so 100mA while it should have been around 300mA
There must be something wrong with my understanding
I have a 50va 15-0-15 rcore
Using a 10r mosfet source resistor gives 1.2 odd volts across the resistor.
This translates to 120mA,where did the rest go?
Again paralleling 2 10r gives 1 V across the resistor, so 100mA while it should have been around 300mA
There must be something wrong with my understanding
The Mosfet Vgs rises with higher current setting and nears the particular Leds total. Either stronger Vf Leds or smaller setting resistors will do the setting you aim at. If you got enough Vin-Vout then all is a matter of particular semis characteristics. How high a DC you can measure across the bigger smoothing electrolytics?
Thanks Salas, the Caps are flush mounted on PCB and measuring them without unmounting is not possible.
For the time being I have used 2 1r in series pushing bias to ~500mA
For the time being I have used 2 1r in series pushing bias to ~500mA
With 15VAC Tx should be enough if your mains don't sag much anyway. Listen at 500mA and tell us if you can hear any better music.
Too much of the good thing is not good for me ;-).
500mA for me adds dollops on bottom taking chunks out of mid & top.200mA for me.
Hey its winter 🙂
And where in the world would you get the last real stand of the royal Bengal tiger (sunderban - 70miles)....drive on seabeach (90 miles)
Sip you favourite poison while seeing the sun setting on third highest peak of the world (300 mile)
500mA for me adds dollops on bottom taking chunks out of mid & top.200mA for me.
Hey its winter 🙂
And where in the world would you get the last real stand of the royal Bengal tiger (sunderban - 70miles)....drive on seabeach (90 miles)
Sip you favourite poison while seeing the sun setting on third highest peak of the world (300 mile)
Last edited:
I didn't notice any real difference after 300mA. I'm sure that some guys hear a difference because they have paid for it.
You shouldn't lose any detail though unless trafo isn't big enough to supply the current.
You shouldn't lose any detail though unless trafo isn't big enough to supply the current.
Last edited:
Hello,
I have two matched quartet of 2sk170: 9.11-9.10 / 9.03-9.04 (BL grade) and 6.07-6.07 / 6.18-6.18 (these are GR, but fall into the >6mA range). Which quartet should I use?
The other unmatched six around which values are better?
Thanks
I have two matched quartet of 2sk170: 9.11-9.10 / 9.03-9.04 (BL grade) and 6.07-6.07 / 6.18-6.18 (these are GR, but fall into the >6mA range). Which quartet should I use?
The other unmatched six around which values are better?
Thanks
Thanks Salas.
I also would like to add about 2cm of wire to the legs of the MOSFETs, to spread them a bit more on the sinks, and to keep the sinks detached from the board. Oscillation problems or I'm still in a safe range?
I also would like to add about 2cm of wire to the legs of the MOSFETs, to spread them a bit more on the sinks, and to keep the sinks detached from the board. Oscillation problems or I'm still in a safe range?