That is what I thought and expressed that concern, similarly with M2 and saturating the Edcors. I was told not to worry, and if my M2 is saturated or anything else it still sounds awfully good.
I may have not expressed concerns enough, or may not have listened correctly to the replies, but I asked more than once...I will see if I can find the threads...I know one was in the "Wayne's 2018 linestage" thread and it came up elsewhere in another thread like this one.
This is probably one of MY misunderstandings I'm sure. Many here, if not most are way more knowledgeable than I am am. I can solder well, Identify parts and know a little bit from all mistakes I've made. You know what they say, "A little knowledge is a dangerous thing".
I really have no idea,
Russellc
I may have not expressed concerns enough, or may not have listened correctly to the replies, but I asked more than once...I will see if I can find the threads...I know one was in the "Wayne's 2018 linestage" thread and it came up elsewhere in another thread like this one.
This is probably one of MY misunderstandings I'm sure. Many here, if not most are way more knowledgeable than I am am. I can solder well, Identify parts and know a little bit from all mistakes I've made. You know what they say, "A little knowledge is a dangerous thing".
I really have no idea,
Russellc
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In a dc coupled amplifier it will amplify the DC for sure. The f5 will amplify the dc approx 15 times...so 100mv in is going to be over a volt on the speakers.
An amp like the m2 has a transformer Which will block dc. Transformers don’t pass dc. Now the transformer might not like the DC but it won’t pass it unless it fails.
Other power amps have an input cap or caps on output. But the F5 is DC coupled.
That was my response, re the transformers in M2 not passing DC. One member put the transformers from the F6 on his outputs for a little more gain (talking about Wayne's 2018 LS) and in response to this as solution instead of output caps to block DC on my waynes 2018 LS, I was told that wouldnt help.
I'll comb that thread for it, but this came up elsewhere in another thread as well.
I probably misunderstood things here, but these were concerns and beliefs I have held since I began this hobby. That said, many things I held onto in those days has been disproven.
I have always contended (and I will be the first to admit I may definitely be wrong) that preamps should have tiny amounts, really tiny amounts of DC on output..if any. Like you I also thought DC could be amplified by the power amp. Also that DC connected front ends if went south and dumped dc, it would go to power amp, be amplified and smoke speakers. Also, that this was particularly a problem with a direct coupled amp like F5.
I have held beliefs in this hobby before and been wrong, I do not have that kind of expertise here to say definitively.
IDK,
Russellc
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The transformer will block DC. This is physics. But DC will also ruin the performance of a transformer like what is used in the F6. Maybe even damage it if there is enough DC.
Output transformers like used in tube amps are a different animal. They can handle DC.
Back to the BA-3 front end...this is a circuit that is not DC stable. Could be DC stable if it had feedback...but then it would be called an F5. So Nelson gave us caps on the output which is fine. A cap is WAY more linear than any transformer.
BA3 is one of my favorite Papa amps. I like it as a front end as well, I have two of them. F5 was my first Pass clone piece. Finally, something I could build that didnt cost a fortune and outplayed at least in my opinion, all my tube stuff. I even sold my MC-225 over it. I realized I can build better.
Before my "Jfet conversion" I was all tube, everything except source. For FM, was tube there still have a Mcintosh MR-67. After Pass clones I sold most of my tube stuff. Still have big KT-88 P-P power amp and some preamps. No DC got past output transformers on them.
Chasing Jfets and exotic output devices, expensive as it can be, is cheaper than tubes I would chase down. Still have my Hickok tube tester too....who knows.
Russellc
Before my "Jfet conversion" I was all tube, everything except source. For FM, was tube there still have a Mcintosh MR-67. After Pass clones I sold most of my tube stuff. Still have big KT-88 P-P power amp and some preamps. No DC got past output transformers on them.
Chasing Jfets and exotic output devices, expensive as it can be, is cheaper than tubes I would chase down. Still have my Hickok tube tester too....who knows.
Russellc
What value do you have on the stepped ladder? Have you or anyone compared with stepped shunt vs ladder on low volume?
I will look that up 
My first thought was that BA3 has an input impedance of 47k(?). So a low value of pot is better. Second thought is if the source sees example 10k even in low volume with ladder compared with a 10k shunt that have a bigger impedance on low volume, right?
So how do the sound differs with shunt vs ladder on low levels?
I’m struggling to understand the impedance so don’t take my questions as science.
My first thought was that BA3 has an input impedance of 47k(?). So a low value of pot is better. Second thought is if the source sees example 10k even in low volume with ladder compared with a 10k shunt that have a bigger impedance on low volume, right?
So how do the sound differs with shunt vs ladder on low levels?
I’m struggling to understand the impedance so don’t take my questions as science.
Nice I been looking at that in 10k.
I searching for a good sound at the volume “husch, the children is sleeping”.
The difference between shunt and ladder is not big at all if I look at resistor values, if you have like me a dac with utput of 75ohm. So I paired BA3 with F4 instead of F6. Less gain with clearer image. Thats the beauty of this DIY, to mess around.
I been looking at that in 10k.I searching for a good sound at the volume “husch, the children is sleeping”.
The difference between shunt and ladder is not big at all if I look at resistor values, if you have like me a dac with utput of 75ohm. So I paired BA3 with F4 instead of F6. Less gain with clearer image. Thats the beauty of this DIY, to mess around.