expensive
oh sorry my failure.
the bass is powerful.
i will post some pics when i put all inside the enclosure.
another amp lives
Hi all,another amp lives.Left offset 5.1mv.right offset 3.1mv.Im lucky,DEAD silent no hum.Amp worked perfect from start except for a crackling left channel due to faulty pot.I had to do a makeshift rewire on the spot and directly connected RCA to input.I couldn't wait for a new pot.😀Soundstage got bigger compared to my p2p chipamp.I will have to wait to play it loud on my bigger speakers as its late here🙁...On a side note,can anyone describe or explain what a "forward"sounding amp sounds like?
Brant-
Hi all,another amp lives.Left offset 5.1mv.right offset 3.1mv.Im lucky,DEAD silent no hum.Amp worked perfect from start except for a crackling left channel due to faulty pot.I had to do a makeshift rewire on the spot and directly connected RCA to input.I couldn't wait for a new pot.😀Soundstage got bigger compared to my p2p chipamp.I will have to wait to play it loud on my bigger speakers as its late here🙁...On a side note,can anyone describe or explain what a "forward"sounding amp sounds like?
Brant-
Attachments
Way To Go bitoman !!!
Nice clean and substantial build. To me "Forward" sounds like a combination of clarity and front to back voice/instrument placement. Many amps sound like there is curtain between the performance and the listener. A good forward sounding amp gives the impression the listener has moved closer to the stage. A bad forward sounding amp has an aggressive presentation that eventually leads to ear fatigue. The trick is to maintain the "Live" nature and presence and eliminate the edginess, that at first listening, can seem inviting and impressive.
I've built a few non-chip discrete amps over the past months and though the sound is excellent, none have produced that "good forward presence" that the FEs are capable of.
Nice clean and substantial build. To me "Forward" sounds like a combination of clarity and front to back voice/instrument placement. Many amps sound like there is curtain between the performance and the listener. A good forward sounding amp gives the impression the listener has moved closer to the stage. A bad forward sounding amp has an aggressive presentation that eventually leads to ear fatigue. The trick is to maintain the "Live" nature and presence and eliminate the edginess, that at first listening, can seem inviting and impressive.
I've built a few non-chip discrete amps over the past months and though the sound is excellent, none have produced that "good forward presence" that the FEs are capable of.
Last edited:
It seems I forgot to order the BC639-16 & Bc640-16 transistors am I ok to use ordinary ones like those in the DC & speaker protection circuit.tia.
It will work and sound fine but not as good as -16 versions...
The -16 are selected for higher Hfe and output impedance of the regulator depends on it.
If you can't find BC639-16 and BC640-16 locally you can replace them with BD139-16 and BD140-16, same parts in different packaging.
Thank you Dario.Now I've read it again I seem to recall you posting this before.Anyway they are in stock at Farnell so I will use these.
Thanks,I dont know if you're asking me but I dont see why not theres a lot of room.
Thanks for that.Makes sense from comparing my other lm3886 amps.🙂
Ah,not so lucky after all but still very happy. With music paused and my ear an inch from speaker I have a soft hum. I suspect input caps and my hack wiring are causing it. These OCK71-4s are touchy-Just slightly brush along them with your finger can cause noise at speaker...By the way have any of you noticed more hum when working near fluorescent type lighting?
I had three cfls connected to the same outlet and it made no difference in the sound. When I tested the amp in my shop it was connected to the same circuit that had three 48" t8 fixtures. They also made no difference.
That's one of the sneakiest interference sources. I have read that newer versions of fluorescent aren't as much of a problem.
The other one is Halogen lighting which can send it's garbage from room to room. I can hear the actual frequency of the noise change on my BrianGT amps (in one particular location) and my Sony Boom Box when I adjust the light. Those builds have metal covers but it's about the thinnest aluminum available.
One other that shows up with bench work is the path of mains cables in the wall behind your work location. As Andrew often preaches, twisting or even braiding everything is a necessary technique to eliminate that interference potential.
Last edited:
I do not ever recommend braiding.
That increases inductance, not good.
You want capacitance between the cores to act as a filter to the high harmonics.
Twisted pair with thin insulation is in my view best for cables.
Flat & thin copper tape with very thin insulation is probably even better, but I have never come across it and have no idea how robust this would be in normal handling. How does one maintain the flat tape across a joint, to PCB, or to connector?
