Are you okay with DIY? Of all the preamps that I have tried, I like the BA2018. However, I have recently been bypassing it and running my amp directly off of my DAC. The BA3, BA2018 and PassDIY type preamps all have a little flavor one way or another.
I assume you are forgoing tube to see what the amp sounds like without much or any coloration to the input signal. I haven't tried it yet, but Zen Mods Iron Pre would be the better option if you wanted to hear the amp's flavor by itself. The volume control is special on that preamp.
I assume you are forgoing tube to see what the amp sounds like without much or any coloration to the input signal. I haven't tried it yet, but Zen Mods Iron Pre would be the better option if you wanted to hear the amp's flavor by itself. The volume control is special on that preamp.
@Zen Mod @Mikerodrig27 I see the Iron Pre and the SissySIT both. Interesting. Yep, this would be tubeless as you noted why. Just to try something different. A friend and I have peeked and listened to some Autoformer based setups too. I think I'm looking for something really basic, low complexity. I don't mind updating a vintage pre as long as there is less clutter, good iron inside. Appears I have some homework to do, thanks for the assignment 🙂
I will never be done with experimentation. Really it blows my mind sometimes just to hear the differences between this unit and that unit! Both can be wonderful but in different ways. These days, I am stuck on the idea of using the Aikido preamp. It matches best with my phono pre and provides what I want in sound to the 'remade Forte 3. To be clear my Forte' 3 is no longer the 3 as it were. That would be one reason that I want to get the real Forte' 3 from Denver. Just another experiment, but I have always been impressed with the 3 untouched except for that which it needed to operate its best. You know, new caps and such. For me, not even a class A revision.
"buffering" is something Paul McGowen at PS Audio talked about recently in a preamp video, something to do with stabilizing the signal and keeping the impedance "low". Apparently the impact of doing this somehow enables a fuller (less lean) sounding preamp and more impactful and engaging presentation.
I'm not sure if I'm describing it accurately, however it kinda helps to explain partly why a straight volume control can sound sound lean without "buffering", and other tricks going on inside a preamp to make it sound better, smoother, more enjoyable. Always been curious about this.
I'm not sure if I'm describing it accurately, however it kinda helps to explain partly why a straight volume control can sound sound lean without "buffering", and other tricks going on inside a preamp to make it sound better, smoother, more enjoyable. Always been curious about this.
@Mikerodrig27 @Ixnay Final update as promised.
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I’m pleased to report the upgraded Forte 3 > 1a Class-A 50 watts is now exceeding my expectations.
Pros:
Nice tone
Nice texture
Nice midrange
Nice sound stage
Smooth
Not grainy
Musical
Engaging
Cons:
Slightly less depth than my tube amps (85%)
Slightly narrower sound stage side to side (85%)
Neither of these are cons really. Nice as-is.
Surprises:
Some times it can have just a little bit more texture than my tube amps, ever so slightly. Kinda hard to believe. Also, with the upgrade and the improved connectorless solder connections and improved bridge rectifier mods, it’s more transparent than I was expecting. Subtly transparent without being too much, the body in the midrange is there without being too lean.
When paired with my Cary SLP-98 6SN7 triode tube preamp, it’s a very nice pairing with my preamp and custom speakers.
Summary Conclusion:
I’m super happy that I went with full Class A configuration as part of the upgrade. Nothing more to do. Done.
Have not had a desire to hurry up and swap back to my mono tube amps yet. Staying put. Might leave it as-is for a couple of months.
Got lucky, it worked.
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I’m pleased to report the upgraded Forte 3 > 1a Class-A 50 watts is now exceeding my expectations.
Pros:
Nice tone
Nice texture
Nice midrange
Nice sound stage
Smooth
Not grainy
Musical
Engaging
Cons:
Slightly less depth than my tube amps (85%)
Slightly narrower sound stage side to side (85%)
Neither of these are cons really. Nice as-is.
Surprises:
Some times it can have just a little bit more texture than my tube amps, ever so slightly. Kinda hard to believe. Also, with the upgrade and the improved connectorless solder connections and improved bridge rectifier mods, it’s more transparent than I was expecting. Subtly transparent without being too much, the body in the midrange is there without being too lean.
When paired with my Cary SLP-98 6SN7 triode tube preamp, it’s a very nice pairing with my preamp and custom speakers.
Summary Conclusion:
I’m super happy that I went with full Class A configuration as part of the upgrade. Nothing more to do. Done.
Have not had a desire to hurry up and swap back to my mono tube amps yet. Staying put. Might leave it as-is for a couple of months.
Got lucky, it worked.
What I like mostly is the actual differences between the two types of amps. Over the past 40 years, this is my 7th Class A/AB solid state amp and 5th tube amplifier set and, yet only a few of them have been truly Class A. I could probably ratchet up bias on my tube amps a bit more, yet trying to spare tubes a bit more. So, it's kinda nice to let the Forte sing a while and not worry as much about keeping two sets of spares on tap all of the time. And to your point, we'll see how it pans out after switching back. Looking forward to delaying that for a while, it's been an interesting experiment so far 👍
I've used my Forte to great satisfaction with a wide range of vintage preamps, although I don't really prefer my Forte preamp. I've used the amp with APT Holman, Threshold FET Ten/HL, FET Ten/e, Mark Levinson No. 38, Marsh, and others. I've read that the Forte preamp and amp were designed to be synergistic, but I have found other preamps to sound better through the amp. I've also used the amp with various tube preamps, and think it performs better with a good SS preamp.
@decooney:
I must admit to being surprised at the much increased capacitance installed in your converted amp. Can you provide info on which caps were used? There seems to be very little room for increased diameter caps in the amps without some fabrication.
Did you take any photos after conversion/completion?
Cheers,
Greg
I must admit to being surprised at the much increased capacitance installed in your converted amp. Can you provide info on which caps were used? There seems to be very little room for increased diameter caps in the amps without some fabrication.
Did you take any photos after conversion/completion?
Cheers,
Greg
From 24,000uF to 100,000uF is quite a jump, both in value and size. Seems they would need to be staggered in order to fit, no?
Ahh, you are right. That is quite a jump. I would be curious to see as well. They must be larger in size.
@Mikerodrig27 @GKTAUDIO yes, a big jump and visually taller, I held one in my hand when I dropped off the amp. Did not measure height, diameter looked close to the same but like 40% taller?
When we started this process, I was like wow, tell me more about the conversion and why - again. The taller caps caught my attention, made me stop and think. Apparently, these taller caps only used on this upgrade/class A conversion he does. Said “the conversion has more grunt with these caps”, …voltage down, bias up, Class A 50w. I have pre-upgrade photos only. Cover was on when I picked up the amp.
When I pull it out of my rack next 15-30 days I’ll remove cover and take good updated photos. Can’t seem to get myself to swap it out yet. Still letting this unfold a bit more. It’s nice.
When we started this process, I was like wow, tell me more about the conversion and why - again. The taller caps caught my attention, made me stop and think. Apparently, these taller caps only used on this upgrade/class A conversion he does. Said “the conversion has more grunt with these caps”, …voltage down, bias up, Class A 50w. I have pre-upgrade photos only. Cover was on when I picked up the amp.
When I pull it out of my rack next 15-30 days I’ll remove cover and take good updated photos. Can’t seem to get myself to swap it out yet. Still letting this unfold a bit more. It’s nice.
@Mikerodrig27 @GKTAUDIO oh, and what I failed to communicate is how I continue to hear some additional smoothing going on after 2-3 weeks of playtime, post upgrades/conversion (model 3 to 1a) Class A 50w. Also, while it warms up quickly within 60m, I DO notice a nice added character of sound, nice tone, stage opened and widened slightly, very nice layering, slight added smoothness kicking in, particularly after @3hrs of play time.
Ask:
Can anyone imagine or make an educated assessment as to why the sound is still smoothing out, improving, still changing after 3wks of play time?
[i.e. new power caps settling in?, new bridge rectifiers?, different taps on transfomer burning in?, Cardas binding posts? all new solder joints? all?]
Ask:
Can anyone imagine or make an educated assessment as to why the sound is still smoothing out, improving, still changing after 3wks of play time?
[i.e. new power caps settling in?, new bridge rectifiers?, different taps on transfomer burning in?, Cardas binding posts? all new solder joints? all?]
I think the most likely are the capacitors, being electrochemical (and gargantuan), are changing, and you are adapting to the sound. Not likely is the rectifiers or binding posts or solder joints are burning in, and certainly the transformer taps aren't burning in - the entire transformer has been powered since new.