Hi X or others,
The smd caps on the bottom side of the All C's pcb have no polarity, correct?, and can be just placed and soldered. First time with paste and hot air, so wanted to be correct.
Thanks,
MM
The smd caps on the bottom side of the All C's pcb have no polarity, correct?, and can be just placed and soldered. First time with paste and hot air, so wanted to be correct.
Thanks,
MM
According to the schematic on his Etsy page - they are non-polar.
As long as you bought the exact ones he spec’d then “yes” they can be placed either way.
As long as you bought the exact ones he spec’d then “yes” they can be placed either way.
The SMT caps are multilayer ceramic so non polar. They only polarity sensitive caps are the big electrolytics on top.
I have used polar SMT “chip” style caps before but they will have a marking and they are huge. Tantalum typically.
I have used polar SMT “chip” style caps before but they will have a marking and they are huge. Tantalum typically.
Kokanee,
Good luck with your build. Please post some photos to document your work and progress.
I have a pair of PCBs waiting, but have no experience with SMT soldering and will watch your work with interest.
Good luck with your build. Please post some photos to document your work and progress.
I have a pair of PCBs waiting, but have no experience with SMT soldering and will watch your work with interest.
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Hey guys, this amp has SMT compensation caps as optional - they are in parallel with through hole equivalent on the other side (typically silver mica’s). But do not fear the SMT caps. They are ever easy to install: use iron to tin one pad first; install chip cap with tweezer and use tweezers to apply pressure on top of part while applying heat to end with pre-tinned pad until it melts and flows; then solder the other end; done.
X,
Thinking over your statement above I wondered what might be the reason. I would appreciate it if you could find time to unpack these statements a bit. Any thoughts on the cause?
I’m have more experience in the world of tubes, and there some folks think the wave crossover region (between push and pull) is exaggerated by highly sensitive speakers, and consequently people with their 105 db at 2.83v corner horns prefer single ended low watt amps. Is this why FH9HVX sounds “better” on low sensitivity speakers, or at high volumes?
Mostly, I am saying that if you have speakers that need 50w to sound “alive” then a 39w amp is not going to sound as good because it is operating near clippping. Within its operating range, the class A Alpha Nirvana with its dominant second harmonic and descending higher orders will sound better. The FH9HVX is barely working at 39w and far away from clipping (the dominant source of distortion). Both amps have quite low THD but I believe the FH9HVX is lower, however, it has a slightly higher third harmonic distortion than the second so may sound a bit brighter on leading edge percussion. Some people like that, it’s very subtle. If I only had the Alpha Nirvana, I would build 89dB and higher speakers to pair with it. If I have 82dB speakers, I would use the FH9HVX. What is true though, is that both amps are pleasing to hear and non fatiguing. Can listen to them endlessly all day all night. Hope that helps.
They are both great sounding amps - just different applications for speakers. If you have a 9W SET tube amp, I would use >95dB sensitive speakers. Etc.
They are both great sounding amps - just different applications for speakers. If you have a 9W SET tube amp, I would use >95dB sensitive speakers. Etc.
Thanks for your reply. Much appreciated.
I have both sets of PCBs (with parts and transformers) waiting to be built; this winter hopefully. So, I will be able to hear both amps on my 92 dB Elsinore loudspeakers. And compare (listen) to a variety of tube amps in my stable. I hope to hear differences and be able to characterize them.
I have both sets of PCBs (with parts and transformers) waiting to be built; this winter hopefully. So, I will be able to hear both amps on my 92 dB Elsinore loudspeakers. And compare (listen) to a variety of tube amps in my stable. I hope to hear differences and be able to characterize them.
Back to soldering, I am going to use my hot air system rather than iron. I have watched videos on both operations, and they are both very straight forward. I anticipate no problems. Will post after completion of the whole pcb.
MM
MM
Francois G,
Good luck with the build and look forward to your listening impressions.
As X has already pointed out the SMD components are optional - you can opt for the through silver mica capacitors also; so don't let that hold you back.
Have you got your chassis sorted out?
Good luck with the build and look forward to your listening impressions.
As X has already pointed out the SMD components are optional - you can opt for the through silver mica capacitors also; so don't let that hold you back.
Have you got your chassis sorted out?
Zman01,
Thanks for your comments and encouragement. I think I do have my chassis sorted out! My Alpha Nirvana will have 12x12 inch heatsinks for sides (I bought these hunks years ago) and finished hardwood front & back (width to suite and with any additional heatsinks and connections). Top would be perforated stainless steel with Noctua fan sucking down (when necessary, controlled by temp) from the bottom. It would be a cube-like stereo amp, probably close to 12x12x12 inches. Sounds OK
?
FH9 is easier, but similar 12” height heatsink (6” wide) sides and hardwood rest to suite.
Thanks for your comments and encouragement. I think I do have my chassis sorted out! My Alpha Nirvana will have 12x12 inch heatsinks for sides (I bought these hunks years ago) and finished hardwood front & back (width to suite and with any additional heatsinks and connections). Top would be perforated stainless steel with Noctua fan sucking down (when necessary, controlled by temp) from the bottom. It would be a cube-like stereo amp, probably close to 12x12x12 inches. Sounds OK
? FH9 is easier, but similar 12” height heatsink (6” wide) sides and hardwood rest to suite.
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Francois G,
Cube like chassis sounds good, and 12" x 12" heatsink should be (more than) adequate for the Alpha Nirvana, even without the fan.
Looks like you are ready for the builds! 🙂
Cube like chassis sounds good, and 12" x 12" heatsink should be (more than) adequate for the Alpha Nirvana, even without the fan.
Looks like you are ready for the builds! 🙂
That’s a nice hunk of heatsink! Should be fine, especially with a fan to help out when needed.
Elsinores are fine speakers for either amp as they are ~92dB sensitive?
Good luck with the builds and have fun this winter. The Alpha Nirvana will help with the heating.
Elsinores are fine speakers for either amp as they are ~92dB sensitive?
Good luck with the builds and have fun this winter. The Alpha Nirvana will help with the heating.
What preamps are people using with the FH9-HVX? Looking for what would be suitable/needed inbetween a DAC w/ line-level output. I'm seeing the Mezmerize B1 Buffer but believe that would be overkill as I only need a passive preamp w/ 2+ input selector w/ volume control. At the simplest sense I'm aware this is a pot w/ relays, but didn't know if this amp would benefit w/ a full attenuation design preamp.