I have been thinking about building one and only one Pass's Class-A amplifier. I always used BJT based Class-AB for serious builds and recently Chip-Amps and never built a Class-A.
What would be a good Pass Class-A that I should build to experience that? I was looking at F5 and F6, or are there any better ones with readily available components (from Mouser or Digikey)?
Thanks for your suggestions!
What would be a good Pass Class-A that I should build to experience that? I was looking at F5 and F6, or are there any better ones with readily available components (from Mouser or Digikey)?
Thanks for your suggestions!
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Personally, I would look into a Aleph J build, but I tend to prefer Single ended class A instead of push pull. You can't go wrong with an F5 or F6 either, you will be blown away with what ever you choose to build!
I for one is going to try M2x. I too tend to go with BJT based class A/B. M2x also have a BJT input buffer option. And multiple others.
Well, what would be an appropriate pair of speakers for say, F6?
I am thinking of building a pair of Solstice (PE/Jeff B's design)
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If you want to play it safe build one of the designs that will perform well with more difficult speakers loads: F6, F5, M2, Push pull vfet if you're lucky enough to have the vfets.
Always start with a definite decision on speakers, and then determine a suitable amplifier for them.
+1.
Like others have said, your speaker sensitivity, seated listening position, size of room and listening habits, all play a part.
For example, the Aleph J is not bad, output Z is 0.4 ohms, 25 watts into 8 ohms but the amp only puts out about 13W into 4 ohms (since it is a SE output stage) which may not be enough for your listening habits. A benign impedance curve will help. That being said, Magnepans have “benign” impedance curves but they are 83-86 dB efficient with a nearly flat 4 ohm impedance. I don’t recall the phase angles being extreme either. But I would expect the Aleph J to run out of steam in that setup.
Can you link the measurements of the Solstice speaker you are considering?
Best,
Anand.
While I love my Aleph J it really does not like a 4ohm or lower impedance. When I have tried it with inefficient speakers and cranked the volume it loses some of it's magic.
Anand,
The Parts-Express site lists the Solstice kit as 4 Ohms.
The Pass F6 manual mentions that the amplifier's rated output is 25 watts at 8 ohms and 50 watts at 4 ohms, so possibly more suitable from an output power perspective.
The Parts-Express site lists the Solstice kit as 4 Ohms.
The Pass F6 manual mentions that the amplifier's rated output is 25 watts at 8 ohms and 50 watts at 4 ohms, so possibly more suitable from an output power perspective.
It's seems that the F5 is the more ''traditionnal amp'' and Aleph J is at the other side of the spectrum. F4, F6 and M2X are in between.
THe big investment is in the chassis and PSU, who can be retained for any of these amps.
THe big investment is in the chassis and PSU, who can be retained for any of these amps.
Agreed, although I was hoping for full impedance & phase measurements or an avid diy'er to have a built Solstice kit with a Parts Express DATS measurement done. I think every one of us should own this:
Dayton Audio DATS V3 Computer Based Speaker & Audio Component Test System
Dayton DATS v3 | An Absolute Must Have - YouTube
or equivalent (you can do it with REW too, but it takes some extra gear; the DATS is no fuss).
The DATS also has a precision LCR included.
Best,
Anand.
Anand,
This might help on the impedance curve and phase:
Log into Facebook
Still looking for measurements from an actual builder.
+1 on the DATS recommendation.
I have one of the older versions, and find it very useful.
This might help on the impedance curve and phase:
Log into Facebook
Still looking for measurements from an actual builder.
+1 on the DATS recommendation.
I have one of the older versions, and find it very useful.
Thanks for that facebook link! I could find only the following!
Solstice MLTL Measurements | Audio Science Review (ASR) Forum
Solstice MLTL Measurements | Audio Science Review (ASR) Forum
I sort of lurk here, I’m just starting to get back into this hobby after a bit of a hiatus. However, my 2-cents, the M2. I went from a chip amp (LM3886), to a JLH class-A, to a First Watt M2, and I haven’t been able to stop listening to the M2. There’s just something special and magical about that little amp. Here soon I’ll be playing with some VFETs so that may very well dethrone the M2, we’ll see.
Now, I’m currently running Klipsch KG5.5’s, so probably a little different from the Solstices
Now, I’m currently running Klipsch KG5.5’s, so probably a little different from the Solstices
I have an M2 and recently built the F4. Haven’t gone back to the M2. The F4 is so good. It will drive low impedances. Just needs a capable preamp.
Edit: this is not to downplay the M2, which is superb also. Really, you can’t go wrong with either, or the F5. Just depends on how much time you have.
Edit: this is not to downplay the M2, which is superb also. Really, you can’t go wrong with either, or the F5. Just depends on how much time you have.
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