Good effort. Actually most of the people even do not scratch the surface and can’t understand how complex things are that define the end result the actual tone we hear when we play electric guitar. Most misunderstood thing are guitars but closely followed by amplifiers. Issue is amplified by number of the people that are convinced that they understand it but actually have dangerous half knowledge. That promotes one liner myths we often hear. People often give higher importance to things that actually don’t make huge changes. For example different brand of the output tubes. Sure it makes a difference but nowhere near as much the cabinet and the speaker choice will do. Put old Fender and Marshall true the same cabinet and let them overdrive and they will sound Fender alike with Fender cabinet and Marshall alike with Marshall cabinet. Now you mention bypass cap difference and bright cap difference between the Fender and Marshall and that is true. Sure there are bypass caps on mixer resistor of Marshall that also adds some top end. Though that all is not the only thing happening. Check the tones stacks. Topology looks same. Few different values only right? Sure but those values make huge difference. Fender ton stack is more interactive and regulates more. Meaning maximum value will increase given range a lot more than Marshall solution will. Also it allows extended lower range. It”s more scooped as well. But that’s it. Marshall tone stack let’s way more signal true. It gives those Marshall middle range and controlled bottom end. But it all plays together. Closed back cabinets and Celestion speakers add to that. EL34 add to that. Different sized transformers add to that. It all matters. Why 5E3 Deluxe sounds different than AC15? Well everything is different accept for the lack of NFB and fact that they are both cathode biased with similar power levels. 5E3 Deluxe has way older type of the phase inverter. Has lower gain V1. Has older type of tone control. Output tubes sound different. Again different speakers Jensen vs. Celestion. To many things to name them all. Designing an amplifier you can do many different things. Everything will influence the sound and feel. Look at the filtering only. Just barely minimal filtering will feel different and especially with the tube rectifier increase the sag. To much will make it feel stiff. Output transformer. Over dimensioned one will make the same circuit sound way different. For example Hiwatt pa vs standard dr103. Apparently same power stage but PA has output transformer that you can’t really saturate with same circuit. It will sound less pleasant always. Look at the Plexi sound. You can add master volume and do tricks but it will never sound the same as when the complete amplifier starts to overdrive. Important part of its sound is overdrive part of the output stage. Without it it sounds different and sterile. I tend to love cathode biased no NFB amplifiers. Though once you get above 30 Watt things get to wild. At lower power levels differences act differently. High power requires some things to be done differently. Look at the power supply. High power amplifiers tend to have often solid state rectifier. Or look at the 50 and 100 Watt power supply of the some older Marshall amplifiers. 50 Watt has still center tapped full wave rectifier but with two in series diodes for each half way. 100 Watt has only one tap for high voltage and sports 4 diodes full bridge Gretz rectifier. No place to full with old ways. They need high voltage and efficiency so latest principal was used. 100 Watt is having even more filtering. Often it has 8 can caps. Mostly double once as well. Most often dual 50 uF with 500V. 50 Watt will use one cap for the first node and use it in parallel hence 100 uF 500V. The first node of the 100 Watt will have two of them connected in series and parallel resulting in 50 uF 1000V capable combination. With help of strapping resistors voltage is decided equally and actual caps work at pretty easy lower voltage and that makes them last longer. After it 100 Watt adds 6 more can caps making for one stiff power supply. At the other hand every tube rectifier has its first cap limitation. Often you will see that there is no more than 32 uF at the first node. Two 50 uF sections in parallel would ruin the rectifier tube over time. Inrush current is just to high. So you can’t make very powerful power supply with one tube rectifier. Enter the dual rectifiers. But wait then you need 2x w to 3A 5V Hester windings for two tube rectifiers. That’s always on up to 30 Watts used only for heating the rectifier that will also make less B+ voltage. So you see how going diode rectification is more efficient and gives up to 30 Watts more high voltage handling for the same size transformer and gives higher B+. Things are complex. Every little thing maters. Company changes transformer brand and same circuit sounds different. Company changes coupling caps same circuit sounds differently. Company goes PCB it sounds different again. Every little thing matters.
Awesome work Greg..
Thank you for doing this 🙏
Good effort.
Actually most of the people even do not scratch the surface and can’t understand how complex things are that define the end result the actual tone we hear when we play electric guitar.
Most misunderstood thing are guitars but closely followed by amplifiers.
Issue is amplified by number of the people that are convinced that they understand it but actually have dangerous half knowledge. That promotes one liner myths we often hear.
People often give higher importance to things that actually don’t make huge changes. For example different brand of the output tubes. Sure it makes a difference but nowhere near as much the cabinet and the speaker choice will do.
Put old Fender and Marshall true the same cabinet and let them overdrive and they will sound Fender alike with Fender cabinet and Marshall alike with Marshall cabinet.
Now you mention bypass cap difference and bright cap difference between the Fender and Marshall and that is true. Sure there are bypass caps on mixer resistor of Marshall that also adds some top end.
Though that all is not the only thing happening. Check the tones stacks. Topology looks same. Few different values only right? Sure but those values make huge difference. Fender ton stack is more interactive and regulates more. Meaning maximum value will increase given range a lot more than Marshall solution will. Also it allows extended lower range. It”s more scooped as well. But that’s it. Marshall tone stack let’s way more signal true. It gives those Marshall middle range and controlled bottom end. But it all plays together. Closed back cabinets and Celestion speakers add to that. EL34 add to that. Different sized transformers add to that. It all matters.
Why 5E3 Deluxe sounds different than AC15?
Well everything is different accept for the lack of NFB and fact that they are both cathode biased with similar power levels.
5E3 Deluxe has way older type of the phase inverter. Has lower gain V1. Has older type of tone control. Output tubes sound different. Again different speakers Jensen vs. Celestion. To many things to name them all.
Designing an amplifier you can do many different things. Everything will influence the sound and feel.
Look at the filtering only. Just barely minimal filtering will feel different and especially with the tube rectifier increase the sag. To much will make it feel stiff. Output transformer. Over dimensioned one will make the same circuit sound way different. For example Hiwatt pa vs standard dr103. Apparently same power stage but PA has output transformer that you can’t really saturate with same circuit. It will sound less pleasant always.
Look at the Plexi sound. You can add master volume and do tricks but it will never sound the same as when the complete amplifier starts to overdrive. Important part of its sound is overdrive part of the output stage. Without it it sounds different and sterile.
I tend to love cathode biased no NFB amplifiers. Though once you get above 30 Watt things get to wild. At lower power levels differences act differently. High power requires some things to be done differently. Look at the power supply. High power amplifiers tend to have often solid state rectifier. Or look at the 50 and 100 Watt power supply of the some older Marshall amplifiers. 50 Watt has still center tapped full wave rectifier but with two in series diodes for each half way. 100 Watt has only one tap for high voltage and sports 4 diodes full bridge Gretz rectifier. No place to full with old ways. They need high voltage and efficiency so latest principal was used. 100 Watt is having even more filtering. Often it has 8 can caps. Mostly double once as well. Most often dual 50 uF with 500V. 50 Watt will use one cap for the first node and use it in parallel hence 100 uF 500V.
The first node of the 100 Watt will have two of them connected in series and parallel resulting in 50 uF 1000V capable combination. With help of strapping resistors voltage is decided equally and actual caps work at pretty easy lower voltage and that makes them last longer. After it 100 Watt adds 6 more can caps making for one stiff power supply.
At the other hand every tube rectifier has its first cap limitation. Often you will see that there is no more than 32 uF at the first node. Two 50 uF sections in parallel would ruin the rectifier tube over time. Inrush current is just to high. So you can’t make very powerful power supply with one tube rectifier. Enter the dual rectifiers. But wait then you need 2x w to 3A 5V Hester windings for two tube rectifiers. That’s always on up to 30 Watts used only for heating the rectifier that will also make less B+ voltage. So you see how going diode rectification is more efficient and gives up to 30 Watts more high voltage handling for the same size transformer and gives higher B+.
Things are complex. Every little thing maters. Company changes transformer brand and same circuit sounds different. Company changes coupling caps same circuit sounds differently. Company goes PCB it sounds different again. Every little thing matters.
Thanks. Have you seen this one? Agrees with what you said about the cabs. ua-cam.com/video/yHTcCEpUIbk/v-deo.html
@aphekrecordingstudio4274 I haven't yet. UA-cam just gave me this recommendation. Will do.