Increasing bias current in the F6 (and many other amps) will begin to decrease the harmonic distortion and provides more headroom for the amp to operate in class A. The downside is heat and power consumption. Specifically, you’ll see less H2 distortion, which you may or may not prefer.
On that bridge rectifier, I’d recommend at least 200V. 35A and larger is good.
On that bridge rectifier, I’d recommend at least 200V. 35A and larger is good.
One other thing to consider, (except it would not let you biamp) and assuming your power supplies are both the same, is convert them to 1/2 and 1/2 mono blocks.
Remove one board and outputs from each amp, and install them in the other. Then use a heavy duty switch to send the power supply juice to one side or the other.
Great fun for less than 20 bucks, but you won't be able to biamp as such.
Russellc
Reminds me of watching the Barrel house cams at Buffalo Trace distillery for barrels with the big "SW" on them...well, in the old days anyway.
Russellc
Russellc
I offer a different viewpoint. You've completed a Training Wheels project (F6), which has a comprehensive Build Guide for total beginners. F6 also has lots of tutorials and a PCB which obeys the diyAudio Store Universal Mounting Specification (so the pre-drilled heatsinks in the Store chassis save lots of time).
Maybe the next one can be a little more challenging, with fewer Training Wheels and less beginner-handholding and greater opportunity for you to learn and grow as a builder. Maybe the Nelson Pass AB100
AB100 Class AB Power Amplifier
You'll do new things, you'll learn new skills, you'll use new semiconductor devices (power BJTs! what a concept!), you'll expand your horizons. And oh by the way you'll get an amp with LOTS MORE power output, which may come in handy for future loudspeaker experiments, or just future This-versus-That amplifier comparisons.
Maybe the next one can be a little more challenging, with fewer Training Wheels and less beginner-handholding and greater opportunity for you to learn and grow as a builder. Maybe the Nelson Pass AB100
AB100 Class AB Power Amplifier
You'll do new things, you'll learn new skills, you'll use new semiconductor devices (power BJTs! what a concept!), you'll expand your horizons. And oh by the way you'll get an amp with LOTS MORE power output, which may come in handy for future loudspeaker experiments, or just future This-versus-That amplifier comparisons.
Thanks Mark Johnson. I may do that in the future. Currently, I'm on assignment working from an apartment; so my listening is generally near field at low SPL's to keep my neighbors happy. I would certainly like to go through the exercise of choosing power supply components and heat sinks based on proper calculations.
Russellc, that's interesting. So, I'd have a different mono-block for each speaker to compare? Or, did I miss something?
Thanks Codyt. I don't have any distortion measurement equipment; so I wouldn't know how much H2 has been reduced after properly setting the bias. I think I was getting some odd order harmonics, because the sound is smoother now.
While I still prefer the mids in the Aleph J, the overall system with the F6 is the best sound I've ever heard. I haven't ever heard such finely detailed separation of instruments. When I try to work with music in the background, I literally get distracted by pieces I've heard hundreds of times.
Several years ago, when I first wanted to build from diyaudio, an audiophile friend encouraged me to buy McIntosh gear. I shelled out, big time, for a C50 and an MC275. The DAC in the C50 is a nightmare (e.g. locks up with format changes via USB); but I always thought the 275 sounded very good. In fact, it does sound very good and had brought my attention to detail previously unexposed in well known content.
That process is happening all over again; this time with added depth and phenomenal staging. That may be partly due to the B1K, but the resolving capability of the F6 is amazing. I'm in awe. Thank you, Mr Pass!
Russellc, that's interesting. So, I'd have a different mono-block for each speaker to compare? Or, did I miss something?
Thanks Codyt. I don't have any distortion measurement equipment; so I wouldn't know how much H2 has been reduced after properly setting the bias. I think I was getting some odd order harmonics, because the sound is smoother now.
While I still prefer the mids in the Aleph J, the overall system with the F6 is the best sound I've ever heard. I haven't ever heard such finely detailed separation of instruments. When I try to work with music in the background, I literally get distracted by pieces I've heard hundreds of times.
Several years ago, when I first wanted to build from diyaudio, an audiophile friend encouraged me to buy McIntosh gear. I shelled out, big time, for a C50 and an MC275. The DAC in the C50 is a nightmare (e.g. locks up with format changes via USB); but I always thought the 275 sounded very good. In fact, it does sound very good and had brought my attention to detail previously unexposed in well known content.
That process is happening all over again; this time with added depth and phenomenal staging. That may be partly due to the B1K, but the resolving capability of the F6 is amazing. I'm in awe. Thank you, Mr Pass!
F6 is a great amp. I’m consistently swapping F6 and Aleph J back and forth in my system. If I didn’t enjoy building so much, I could easily stop with either of those amps and be happy the rest of my days.
Having said that, if you ever run into a pair of the semisouth parts, try putting them in the AJ. For me, an AJ with semisouth output is a perfect blend of AJ and F6.
Having said that, if you ever run into a pair of the semisouth parts, try putting them in the AJ. For me, an AJ with semisouth output is a perfect blend of AJ and F6.
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Yes. Given the price and scarcity of the Sony VFETs, I am mounting the
output transistors and enough parts to protect them and allow a
functional test.
This kit is designed to be friendly to newbies as well as you sophisticates,
and this way there will be fewer tears.
Don't worry, there are parts to add, and you can still pick your own
caps. It's powered by a desktop supply and I designed a nice little
filter to take the noise out.
There will be options for five, count 'em, five front end designs,
one of which is my M2 input stage, and the others are Mark Johnson's.
(collect them all!)
And wait till you see the chassis....
I'm a little lost. I see the Sony VFET boards in the store, but I don't see how to pre-order any kind of kit. Can someone let me know where I can claim my place in line?
