Tube rolling in Hagerman Trumpet MC

To all,

thanks for conversation.

@chickenoregg 

I am impressed that you are willing to send out tunes on approval.  Please pm me, I would like to see if we can work together.

@lewm 

Thank you for your comments and advice.  Yes double the heater current was concerning to Jim, and he is very honest, so I am going to do what he advises.

To those who recommend the Sbooster, I asked about this too.  I noticed on looking over the schematics that Mr. Hagerman used a 555 “chip” as an internal power supply to get the voltage to the rails (at least that is what it looks like to me with my very limiter ability in that area).  So, if there is no way to bypass the internal switching power supply,, how would and external LPS make any real difference?  JH, basically had the same opinion and also said that some folks who tried it reported improvement.  
Given confirmation bias, etc., I would be happy to try an Sbooster if someone would loan one to me to try.  I would cover shipping both ways if needed.  Otherwise I am content to leave that out.

My new speakers should be here soon and I am pretty sure they will make a much more significant difference in the sound of my system.

555 is a timer, probably used to delay application of plate voltage after filament voltage is first applied after turn on.

To those who recommend the Sbooster, I asked about this too. I noticed on looking over the schematics that Mr. Hagerman used a 555 “chip” as an internal power supply to get the voltage to the rails (at least that is what it looks like to me with my very limiter ability in that area). So, if there is no way to bypass the internal switching power supply,, how would and external LPS make any real difference? JH, basically had the same opinion and also said that some folks who tried it reported improvement.  

Given confirmation bias, etc., I would be happy to try an Sbooster if someone would loan one to me to try. I would cover shipping both ways if needed. Otherwise I am content to leave that out.

 

Well, speaking from my own experience, the difference from the switching power supply to the sbooster was not a subtle one at all. It was pretty transformative. As to why, I don't know enough to really answer authoritatively. I have a general understanding that switching power supplies are "noisier" and that good linear power supplies (like the sbooster) have a lot more power filtering. That being said, I highly recommend the power supply upgrade over a tube one any day of the week.

Yes, 555 is usually a clock function, looked like it was doing more than that to me, like it was somehow involved in getting higher dc voltage to the rails.  But, my ability to read the schematic is pretty poor, so…

When I asked, I saw another post a while back someone asked JH about it and he said it didn’t make much sense that LPS would make any difference.  But, I am open to trying it as long as I don’t need to put $500 into what might make no difference in my system.  I could see where if one had a mostly digital system, the noise from a switching power supply could cause some interference.  My chain is strictly analog.

There are such things as well designed SMPSs that don't add any more noise than a good linear supply, like in the Berning amplifiers for many years now. I would not fret about a well designed SMPS, and I feel confident Hagerman knows what he is doing.  They got a bad rap because often used in el cheapo gear, which the Hagerman is not.  On the other hand, if you have good evidence that the linear supply is better  in this particular unit, then I do understand your dilemma. Why not enjoy what you have for a while and then consider the upgrade at a later date?