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Hoffman Amps Forum image Author Topic: Fender 5F6A bassman  (Read 24590 times)

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Offline mresistor

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Re: Fender 5F6A bassman
« Reply #100 on: January 20, 2022, 10:14:05 am »
Here's a vid of '59 bassman with a reissue '59 Les Paul to get an idea of hummers through it.



and the vid following it 

Offline 66Strat

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Re: Fender 5F6A bassman
« Reply #101 on: January 20, 2022, 12:29:10 pm »
You may find this info useful.

https://www.youtube.com/watch?v=tU7wXFFZ08w&t=8s

He has numerous videos on his channel of both a 1960 Bassman and a 1959 Bassman. He is totally obsessed with everything Hendrix, which IMO is a GOOD thing.
Regards,
JT

Offline TitaniumValhalla

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Re: Fender 5F6A bassman
« Reply #102 on: January 20, 2022, 01:33:32 pm »
Here's a vid of '59 bassman with a reissue '59 Les Paul to get an idea of hummers through it.



and the vid following it

Sounds great, but there is no stage or studio the average person has access to where they can crank a 5F6A, so to use that as an example of the tones you're going to get out of it on a daily basis is not really realistic.

Offline 66Strat

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Re: Fender 5F6A bassman
« Reply #103 on: January 20, 2022, 02:22:52 pm »
Here's a vid of '59 bassman with a reissue '59 Les Paul to get an idea of hummers through it.



and the vid following it

Sounds great, but there is no stage or studio the average person has access to where they can crank a 5F6A, so to use that as an example of the tones you're going to get out of it on a daily basis is not really realistic.

It is a perfect example of what to expect from the amp. They are LOUD amps. The amps are TOO LOUD for the average bedroom player. But that is a matter of the wrong amp for the wrong venue. Something on the order of 1 to 5 watts would be a better match. Why build/buy a 40 watt amp if you can't play it at a volume where they come into their own. I've owned/played several 40 to 60 watt Fenders. None really start sounding good until you're at least up to 4 or 5 on the volume dial. At that point they are all LOUD.

Edit. FWIW I always loved the sound of a screaming Detroit 6-71 Diesel. I used to haul hay/slop/and cow stuff for a farmer in an old COE GMC with a 6-71. Truly fun to drive, with an absolutely glorious sound. However, they would be HIGHLY FROWNED UPON today as a daily driver.

Example of 6-71 Diesel; however, not in a COE Jimmy truck.
https://www.youtube.com/watch?v=v0I8hYKqGsA
« Last Edit: January 20, 2022, 02:38:53 pm by 66Strat »
Regards,
JT

Offline shooter

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Re: Fender 5F6A bassman
« Reply #104 on: January 20, 2022, 02:55:23 pm »
Quote
they would be HIGHLY FROWNED UPON today as a daily driver.
:l2:
not where I live  :icon_biggrin:
Went Class C for efficiency

Offline mresistor

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Re: Fender 5F6A bassman
« Reply #105 on: January 20, 2022, 03:01:21 pm »
Shooter  - not where I live either.    :icon_biggrin:      so invest in an attenuator.   

Offline 66Strat

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Re: Fender 5F6A bassman
« Reply #106 on: January 20, 2022, 03:17:15 pm »
Quote
they would be HIGHLY FROWNED UPON today as a daily driver.
:l2:
not where I live  :icon_biggrin:

I DO NEED to move. I'm thinking off-grid, maybe West Texas.
Regards,
JT

Offline uki

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Re: Fender 5F6A bassman
« Reply #107 on: January 20, 2022, 05:29:35 pm »
Check out this:



Theory is when everyone knows everything but nothing works, practice is when stuff works but nobody knows why !!!
https://soundcloud.com/ukiuki
http://tribonow.wixsite.com/tribonow

Offline valvetones

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Re: Fender 5F6A bassman
« Reply #108 on: January 20, 2022, 10:29:43 pm »
Cool, cool, and super cool!!!! So glad it worked for you VT. Now were talking. Plexi hmmm..... They were coveted for sure. Pharmrock. Can you please post pictures of your plexi, and upload a video of you playing thru it. VT Please upload a video of you playing thru one of your amps that your in love with the sound. I need to hear. By the way your photos are awesome. Great looking amp. Nice work buddy!!!! Man those are some good size transformers. Is one of those the choke???? Holy cow.
G.

Thanks! Yes one is the choke. It’s a 250 mA swinging choke and it is set up the way fender did it in the tweed twin. Usually the choke only handles the supply to the screens, but in this case, the current of the whole circuit goes through it. Originally I had intended to use it as a choke input filter so I could draw some serious current, but, as luck would have it, the vibrato does not work if the power section is biased for glory, so I’m stuck at 40mA per tube, and just ran the choke like the tweed twin does. Plenty of other stories about could’ve been but didn’t work with this circuit. However, some of my endeavors worked out splendidly.

As for the video post, lol, that would require someone to walk me through it Barney style, and hold my hand like a little child every step of the way!
Lmao

Offline Grees01

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Re: Fender 5F6A bassman
« Reply #109 on: January 21, 2022, 01:39:41 am »
Cool, cool, and super cool!!!! So glad it worked for you VT. Now were talking. Plexi hmmm..... They were coveted for sure. Pharmrock. Can you please post pictures of your plexi, and upload a video of you playing thru it. VT Please upload a video of you playing thru one of your amps that your in love with the sound. I need to hear. By the way your photos are awesome. Great looking amp. Nice work buddy!!!! Man those are some good size transformers. Is one of those the choke???? Holy cow.
G.

Thanks! Yes one is the choke. It’s a 250 mA swinging choke and it is set up the way fender did it in the tweed twin. Usually the choke only handles the supply to the screens, but in this case, the current of the whole circuit goes through it. Originally I had intended to use it as a choke input filter so I could draw some serious current, but, as luck would have it, the vibrato does not work if the power section is biased for glory, so I’m stuck at 40mA per tube, and just ran the choke like the tweed twin does. Plenty of other stories about could’ve been but didn’t work with this circuit. However, some of my endeavors worked out splendidly.

As for the video post, lol, that would require someone to walk me through it Barney style, and hold my hand like a little child every step of the way!
Lmao
  I need video. You can do it. Easy peasy. Do you have a YouTube account?

Offline Platefire

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Re: Fender 5F6A bassman
« Reply #110 on: January 22, 2022, 01:15:22 pm »
I have three 5F6A Bassmans in various forms/conversions. I had to add MV's to control the volume and still get the amp response/feel I needed. I think that's already been mentioned once already but not much discussion on it. To me that makes it workable in any room and situation. Platefire
On the right track now<><

Offline Grees01

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Re: Fender 5F6A bassman
« Reply #111 on: January 22, 2022, 06:23:18 pm »
I have three 5F6A Bassmans in various forms/conversions. I had to add MV's to control the volume and still get the amp response/feel I needed. I think that's already been mentioned once already but not much discussion on it. To me that makes it workable in any room and situation. Platefire
Hey there. Thanks for posting on this thread. Well you must like the circuit if you have built 3 of them. A master volume control was definitely on this list of things to include when contemplating this build. Also the fact that the circuit is so close to a jcm45, and a plexi, is attractive. What's different about the 3 versions that you have? Can you post a video for me please of YOU playing thru YOURS in the video clips section of this forum. I would really appreciate that.
G. Rees

Offline valvetones

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Re: Fender 5F6A bassman
« Reply #112 on: January 23, 2022, 03:09:12 am »
G,Rees

What kinda microphone did you use when you recorded yourself playing on the backing track?

Offline Grees01

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Re: Fender 5F6A bassman
« Reply #113 on: January 23, 2022, 03:07:11 pm »
G,Rees

What kinda microphone did you use when you recorded yourself playing on the backing track?
Whats up VT  :m8 :m8. No mic used. Recorded with my old iPhone and the video file was dropped into Reaper.
G. Rees

Offline Grees01

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Re: Fender 5F6A bassman
« Reply #114 on: January 23, 2022, 03:25:44 pm »
I just wanted to mention that there are quite a few free to try (DAW)'s digital audio workstation out there. All of them have a learning curve to be able to use. But with watching a few intro videos you can be up and running pretty quickly. I'm currently using Reaper, and its free to evaluate, and if you like it, very cheap to purchase at 60.00. Here's the link to Reaper for anyone interested
https://www.reaper.fm/download.php
G.

Offline Grees01

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Re: Fender 5F6A bassman
« Reply #115 on: January 23, 2022, 03:34:34 pm »
Also wanted to mention that smartphones these days do a pretty darn good job recording video and audio. IPhone for sure. I don't have an android phone for comparison. But the specs on all the phones these days are impressive. You can upload your videos to your YouTube channel and share your video here at the forum. I sure would love to see what you've built and hear how it sounds. Please show off a little of your labor of love with the rest of us.....
G.

Offline valvetones

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Re: Fender 5F6A bassman
« Reply #116 on: January 23, 2022, 04:18:50 pm »
“ Please show off a little of your labor of love with the rest of us.....
G.”

I have every intention of doing that.
Might be awhile, but it’s coming.

Stay tuned.

Pun intended  :icon_biggrin:

Offline Grees01

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Re: Fender 5F6A bassman
« Reply #117 on: January 24, 2022, 01:04:52 am »
“ Please show off a little of your labor of love with the rest of us.....
G.”

I have every intention of doing that.
Might be awhile, but it’s coming.

Stay tuned.

Pun intended  :icon_biggrin:
Will do! looking forward it for sure.
G.

Offline Platefire

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Re: Fender 5F6A bassman
« Reply #118 on: January 25, 2022, 12:58:31 pm »
Grees01
I was thinking about my builds, actually I have four variations of 5F6A. Three in the form of heads and one combo.Two conversions of old PA Heads, A Dukane, A Bogen CHB-50, scratch built head Marshall 2204 Head(Plexi) and a Modified Pignose GV-40 Combo.
I'm not sure I could be helpful by offering a clip/video of my playing because what already been presented is light years ahead of my playing. I will say this regarding my MV suggestion. I think a large part of the original 5f6A beauty was in the combination of that old original set up running through that 4-10 cab without the MV caused the power tubes to distort when you turned it up loud enough.That was big part of the sound. Of course it had to be turned up pretty loud to reach clipping. With a MV turned down(the power tube not working hard) and the preamps tube turned up, your not going to get the same feel, thickness and tone as you hear in those previous clips. On the other hand the 5F6A has a great clean sound also and that's what I mostly use and use my pedals for boost, OD and Dist. I set my pre vol around 11:00 O clock and my MV at 8:00 O clock to where my sound is mostly clean with just a little clip with my guitar vol full up. Anything more is pedals.  As you see the power tubes are not getting into the action much with this setting. So I just wanted to make you aware of this with my MV suggestion.

My first amp build was a modified version of the 5F1/5F2 Champ/Princeton Combo I built in 2001 with the help of a internet friend of mine Casey4s. Here 21 years latter with the help of the Hoffman Forum, I am just now getting all my greenhorn mistakes cleared up to where it really sounding good these days. I think it's good to start small and not over-whim yourself on the first build. Platefire
« Last Edit: January 25, 2022, 01:14:42 pm by Platefire »
On the right track now<><

Offline PharmRock

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Re: Fender 5F6A bassman
« Reply #119 on: January 25, 2022, 02:23:34 pm »
My first amp build was a modified version of the 5F1/5F2 Champ/Princeton Combo I built in 2001 with the help of a internet friend of mine Casey4s. Here 21 years latter with the help of the Hoffman Forum, I am just now getting all my greenhorn mistakes cleared up to where it really sounding good these days. I think it's good to start small and not over-whim yourself on the first build. Platefire

I started by adding a tone control to a Valve Junior.  Did a couple of Valve Junior conversions, then built an 18W Lite (which is an awesome amp and fairly "simple"), then gradually increased the complexity to where I am now (Plexi, JTM45).  Just speaking for myself, there is no way I would've felt comfortable starting out my amp-building journey with the JTM45, especially with several "options". 

Offline Grees01

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Re: Fender 5F6A bassman
« Reply #120 on: January 26, 2022, 10:31:47 pm »

My first amp build was a modified version of the 5F1/5F2 Champ/Princeton Combo I built in 2001 with the help of a internet friend of mine Casey4s. Here 21 years latter with the help of the Hoffman Forum, I am just now getting all my greenhorn mistakes cleared up to where it really sounding good these days. I think it's good to start small and not over-whim yourself on the first build. Platefire

Starting with something small and simple is certainly a great suggestion, and makes very logical sense. The problem for me is that I don't want to invest money and labor into an amp that I'm going to end up not liking and not using. I have a Fender Hot Rod Deville 4 x 10 sitting here that I bought many years ago back, in excellent condition, and I just don't very often it at. The sound is not bad. It's 60 watts. A good bit too loud at above 3 on the master volume, but aside from the volume level, I just really don't care for the tone anymore. It has a kind of a piercing type quality to the clean channel that's hard to listen to for long. It's not very 3d sounding even with some reverb turned on, But it was what I used back in the day before I bought my Triple Crown. I haven't personally heard a great sounding small 10-25 watt, single speaker amp to this day. I really wish you would post some video of yours. You don't have to be some super good guitar player for their to be value in the listening to the video. Thanks for sharing on this topic and for the information.
G.

Offline Grees01

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Re: Fender 5F6A bassman
« Reply #121 on: January 26, 2022, 10:48:18 pm »

I started by adding a tone control to a Valve Junior.  Did a couple of Valve Junior conversions, then built an 18W Lite (which is an awesome amp and fairly "simple"), then gradually increased the complexity to where I am now (Plexi, JTM45).  Just speaking for myself, there is no way I would've felt comfortable starting out my amp-building journey with the JTM45, especially with several "options".
I understand where your coming from. For sure. I don't have any doubt with my ability to assemble the "amp" from the mechanical perspective. Where I'm at a loss is understanding how and why things work the way that they do. I don't have good understanding of how the circuit works. I can read and follow the circuit, and build as designated in the design. But what does that get me? Maybe a great sounding amp, depending on what I choose as a design, and the components ect ect. At the same time it leaves me pretty lost if I'm trying to understand why a certain value of resistor, or capacitor or a particular way of wiring a portion of the circuit influences the way it works or sounds. So I'm reading, and studying, and trying to learn how, why, where, what, ect ect. In that regards I could build a champ circuit or a JTM45 circuit, but still lack in understanding the above. I'd rather invest time and money into something that I'm likely to love when finished. I'd like to hear your 18 watt lite. Please post video. Your Plexi build looks fabulous. Please post video asap.
G.

Offline HotBluePlates

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Re: Fender 5F6A bassman
« Reply #122 on: January 26, 2022, 11:45:46 pm »
Sounds great, but there is no stage or studio the average person has access to where they can crank a 5F6A, so to use that as an example of the tones you're going to get out of it on a daily basis is not really realistic.
It is a perfect example of what to expect from the amp. They are LOUD amps. The amps are TOO LOUD for the average bedroom player. ...

You're both right, but I agree more with TitaniumValhalla that the average player will never turn a tweed Bassman loud enough to distort, absent master volume or attenuator/reamper/load-box.

I played an acquaintance's 1958 Bassman in an airplane hangar on ~7, with a 20 or 30ft cord.  The amp was still clean, and it was too loud even in that large space for me to turn it up further.

It's worth noting that Johan's headphones in his videos are the same type you'd use to protect your hearing at an indoor shooting range, except they have a cord & earpieces inside.  Hearing protection is the only way he pulls off many of his videos, because a Bassman would be brutal in the size of enclosed space he's playing.

Offline Grees01

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Re: Fender 5F6A bassman
« Reply #123 on: January 27, 2022, 12:26:56 am »
Sounds great, but there is no stage or studio the average person has access to where they can crank a 5F6A, so to use that as an example of the tones you're going to get out of it on a daily basis is not really realistic.
It is a perfect example of what to expect from the amp. They are LOUD amps. The amps are TOO LOUD for the average bedroom player. ...

You're both right, but I agree more with TitaniumValhalla that the average player will never turn a tweed Bassman loud enough to distort, absent master volume or attenuator/reamper/load-box.

I played an acquaintance's 1958 Bassman in an airplane hangar on ~7, with a 20 or 30ft cord.  The amp was still clean, and it was too loud even in that large space for me to turn it up further.

It's worth noting that Johan's headphones in his videos are the same type you'd use to protect your hearing at an indoor shooting range, except they have a cord & earpieces inside.  Hearing protection is the only way he pulls off many of his videos, because a Bassman would be brutal in the size of enclosed space he's playing.
I would imagine then that it would be similar to my Hot Rod Deville, which is 60 watts without a tube rectifier. Pretty loud at 3, and at 4 it's uncomfortable to listen to. Clean channel, no master volume. However my Triple Crown is 50 watts, no rectifier tube, 4 x 12 slant cab, with independent gains for all 3 channels, as well as master volumes, and then the global volume control and that is wonderful here in my little studio.

Offline PharmRock

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Re: Fender 5F6A bassman
« Reply #124 on: January 27, 2022, 08:42:01 am »
I understand where your coming from. For sure. I don't have any doubt with my ability to assemble the "amp" from the mechanical perspective. Where I'm at a loss is understanding how and why things work the way that they do. I don't have good understanding of how the circuit works. I can read and follow the circuit, and build as designated in the design.

Great points.  If you feel comfortable doing the assembly part then you're right that it shouldn't matter whether its a champ or a bassman.  Troubleshooting would be a lot different between the two, but you have some great resources here on this site and this forum that could help you out with that.

You're both right, but I agree more with TitaniumValhalla that the average player will never turn a tweed Bassman loud enough to distort, absent master volume or attenuator/reamper/load-box.

I bought a reactive load box last year and its been great for getting the cranked amp tone without making my ears bleed.  Even so, you still don't get the effect of the speakers moving all that air.  Just not quite the same. 

Offline CascoSieg

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Re: Fender 5F6A bassman
« Reply #125 on: January 27, 2022, 09:53:10 am »
What about putting together a test-board? I find that really helpful when trying to sort out what my next project will be. There are better (safer) examples of test boards on this forum than mine, but it worked for my purposes, and probably cost me $50 in non-repurposeable parts. I've mocked up PP and SE power sections, and a few different preamps.

Offline Platefire

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Re: Fender 5F6A bassman
« Reply #126 on: January 27, 2022, 12:28:50 pm »
On second thought, I guess the 5F6A Bassman circuit in not that complicated above a Champ in it's original form if you consider it's all amp circuit and don't have a reverb or tremolo circuits to deal with.
On the right track now<><

Offline Grees01

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Re: Fender 5F6A bassman
« Reply #127 on: January 27, 2022, 05:09:47 pm »

You're both right, but I agree more with TitaniumValhalla that the average player will never turn a tweed Bassman loud enough to distort, absent master volume or attenuator/reamper/load-box.

I bought a reactive load box last year and its been great for getting the cranked amp tone without making my ears bleed.  Even so, you still don't get the effect of the speakers moving all that air.  Just not quite the same.

Thanks for posting HBP and PharmRock. So just out of curiosity, I wondered, how loud am I actually playing here in my environment? My neighbors tell me they can hear me, but not to the point of being overly annoying. Late at night 10:00 pm and later I turn it down another notch. My neighbors are pretty cool, and I've been living here a long time. So I checked the Apple App Store for a DB meter. Sure enough there are a few. I picked up one with great ratings, and installed it on my Iphone. Been doing a little checking to have some kind of reference to how "LOUD" I am playing. I figured numbers would be good, after all, things like tone and volume level and such are  subjective. So with my Triple Crown thru the 4 x 12 slant cab, rated at 50 watts at the level that I normally play at I'm at a max of approx 100-105db depending on where on the neck, and my pick attack ect. 80-100 throughout most of the notes. Okay. I plugged into the Hot Rod Deville 4 x 10 ratted at 60 watts, clean channel volume on 3. max db at approx 111 and 85-110 throughout most of the notes. So the next question that came to mind was what db level was comfortable to my ears playing at and for how long? Up to 100db I can play for hours without it bothering me. Once you start going above 100 - 105db it starts to bother over any extended period of time. I think that information is useful with regards to design. One other point to mention; was, at approx the same volume level from both of the amps that I have, is that the sound from the Fender is more grating on the ear at the same db than the Triple Crown which is far more pleasant to listen to. As mentioned previously the Deville has a kind of piercing sound quality that's in general kind of annoying to my ear. I'm not sure technically what to call that, and it's not exclusive to the high register, highest frequency notes, but is more pronounced there. Maybe I could say that the Triple Crown is more "creamy" sounding, and the Hot Rod Deville is more "sharp edged" sounding. Of note is the fact that the TC has a presence control for each channel where the HRD has none. I think that also is a useful piece of information to know with regards to design. I don't like that knife edge sound, and especially when you start really cranking up the volume. It has a painful to ear type of quality to it. I want to avoid that in design. So that's a couple of points with regards to design for me to keep in mind. Now 100-110 db max is just fine for here in my little studio, but if I were to go somewhere and play with friends or something is that enough? Maybe? Enough to keep up with the drummer? Maybe not? Maybe you need 120db in that environment? So is there a way to calculate db relative to watts? The speaker cabinet that I could use is my TC 4 x 12 slant cab wired for 8 ohms for reference? Knowing that value could be very useful in gauging how much power do I need? Another consideration might be where in the operating range of the amp do you want to run? My first thought would be somewhere in the middle of the curve. Where going down in volume cleans things up a bit, hopefully without sacrificing depth, and dimension, and all the things we want, and being able to go up a bit where we start to get some overdrive out of the amp. (from the pre-amp, or power-amp, or maybe both) Knowing that formula for calculating db relative to watts at a given impedance would be good information to have when considering a design. Well I was just doing a little thinking out loud and my fingers were on the keyboard. So.......
G.
Oh one last things that may be helpful to others, Also on the app store I found a sweet little tone generator that does all kinds of neat stuff that I think you could use when building an amp for testing purposes. I used a little adapter and plugged it into my Crown power amp and played around with it 60hz, 440hz and on and on. Found out that my upper limit for hearing is about 14,000 hz. Interesting. The apps name is dB meter for anyone interested. Apple app store. I don't know if they have a version for android.

Offline Grees01

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Re: Fender 5F6A bassman
« Reply #128 on: January 27, 2022, 05:21:46 pm »
What about putting together a test-board? I find that really helpful when trying to sort out what my next project will be. There are better (safer) examples of test boards on this forum than mine, but it worked for my purposes, and probably cost me $50 in non-repurposeable parts. I've mocked up PP and SE power sections, and a few different preamps.
An exceptionally good thought. And thanks so much for sharing. To be honest, I had a very similar though in my head in the past. I never did search for it here on the forum. But in trying to figure out a design that works for you, and in the ability to tweek, and modify it sure looks like a really attractive idea. I remember those bus connectors from being a kid at my dad's shop. He had lot's of them. Is that what their called? The black mounting boards with the screws? I can't remember the correct name.
G.
« Last Edit: January 27, 2022, 05:26:48 pm by Grees01 »

Offline Grees01

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Re: Fender 5F6A bassman
« Reply #129 on: January 27, 2022, 05:34:03 pm »
On second thought, I guess the 5F6A Bassman circuit in not that complicated above a Champ in it's original form if you consider it's all amp circuit and don't have a reverb or tremolo circuits to deal with.
Well for me at least. Not too difficult to layout and assemble, way more difficult to understand!  :icon_biggrin: I'm working on it. Currently reading "Basic Theory and Application of Electron Tubes" Dept of the Army and Air force 1952. Good stuff, not to incredibly hard to understand.

Offline valvetones

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Re: Fender 5F6A bassman
« Reply #130 on: January 27, 2022, 05:37:31 pm »
“It has a kind of a piercing type quality to the clean channel that's hard to listen to for long. It's not very 3d sounding even with some reverb turned on”

Oh yes, they all suck now, lol.


Offline Grees01

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Re: Fender 5F6A bassman
« Reply #131 on: January 27, 2022, 07:53:45 pm »
“It has a kind of a piercing type quality to the clean channel that's hard to listen to for long. It's not very 3d sounding even with some reverb turned on”

Oh yes, they all suck now, lol.
Hey VT!!!!! I'm not quite sure what your getting at? Are you saying all the newer Fender amps suck? or I'm not sure what you mean.
G.

Offline valvetones

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Re: Fender 5F6A bassman
« Reply #132 on: January 27, 2022, 09:46:21 pm »
Sup G’rees

Yes I’m saying they all sound as you described. I’m incredibly picky though.
To my ears, all the new fenders are harsh , ear piercing, lacking warmth, lacking depth, they are just terrible.

I personally think this is because they just don’t make anything like they used to. Every single step in the chain adds to the character of the amp.

The resistors, the capacitors, the potentiometers, the tubes, the transformers, the speakers, the voltage, everything.

It’s just not anything like it once was.

I try to use stuff from the old days as much as possible. I got the tubes, transformers and resistors covered, and some/not all, of the caps.

I do like what Jupiter condenser company is doing. Their copper foil paper in oil caps seem to sound good.
But at $38 a piece, they may be a waste of capital if you can get some older caps that aren’t leaky for $5 each.

I’m currently in the process of building my first 100% vintage nos parts amp. I’ll be running it against the last amp I built.

I’m even going to reform nos electrolytics and use those if it works out.

To me , it’s worth it to embark on this endeavor. I’ll never know until I try.

This next build is really going to be interesting. I was at jam night at Jerry’s Bait shop in Kansas City last night, where all the groovy cats go play. A few friends of mine, and a couple of guitarists I met last night are going to be my control ears for this build. We will all be comparing the last build with this next build and some modern fenders they own.

Should be interesting. A new deluxe reverb, a 65 Twin reissue, and the two vibroverbs I’ll have.

As the one who is the builder, I think it’s best to let the people judge for me, to rule out my own opinion, take a back seat, let the people decide where the tone is.

If the 65 reissue twin wins the competition, I’ll have a TON of parts to sell, lol

I seriously doubt it though. The amount of effort and care taken into parts selection is unrivaled.

I know of no one that going about it this way. 




Offline acheld

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Re: Fender 5F6A bassman
« Reply #133 on: January 27, 2022, 09:50:35 pm »
Not what you (or me) want to hear, but listening at 100dB for even short periods -- 15-20 min IIRC -- can result in hearing loss.   

My gigging buddies are all using hearing protection of one sort or another nowadays.  Not like when I was coming up . . .


Offline Grees01

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Re: Fender 5F6A bassman
« Reply #134 on: January 27, 2022, 10:09:39 pm »
Interesting. I just performed a hearing test with this little dB meter app, and my Iphone, and a set of Iphone earbuds. Pretty cool little test actually. Analysis says I have no hearing loss, but my left ear is a little worse at 95% than the right ear at 100% . Granted it's not a real lab test, but was a little surprising really, given my age, and all the loudness I've endured over the years. Here's a little picture of the results. Cool app.
G.

Offline valvetones

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Re: Fender 5F6A bassman
« Reply #135 on: January 27, 2022, 10:31:22 pm »
Interesting. I just performed a hearing test with this little dB meter app, and my Iphone, and a set of Iphone earbuds. Pretty cool little test actually. Analysis says I have no hearing loss, but my left ear is a little worse at 95% than the right ear at 100% . Granted it's not a real lab test, but was a little surprising really, given my age, and all the loudness I've endured over the years. Here's a little picture of the results. Cool app.
G.

That is interesting!
Doctor iPhone!! Man tech is incredible.

Offline Platefire

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Re: Fender 5F6A bassman
« Reply #136 on: January 27, 2022, 11:35:20 pm »
Grees01
When I was building my first Champ, like you, i was reading everything I could trying to figure out how a tube amp worked.I wanted to know what was happening to your guitar signal from the time it entered the input jack all the way through the amp until it hit the speaker from the OT. To help myself I drew a graphic layout drawing that helped me study it. I was having a hard time understanding how Low voltage AC and High DC voltage was traveling in the same wire at the same time. It seemed like a train-wreck in action. Then I read how Coupling Caps(Capacitors) blocked the high voltage DC and allowed the low voltage AC that the guitar signal is riding on to pass. Har! That was a major breakthrough for me. Attached is my drawing/Graphic Layout I did way back then. Platefire
« Last Edit: January 28, 2022, 07:46:52 am by Platefire »
On the right track now<><

Offline Grees01

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Re: Fender 5F6A bassman
« Reply #137 on: January 28, 2022, 12:50:24 am »
Sup G’rees

Yes I’m saying they all sound as you described. I’m incredibly picky though.
To my ears, all the new fenders are harsh , ear piercing, lacking warmth, lacking depth, they are just terrible. I personally think this is because they just don’t make anything like they used to. Every single step in the chain adds to the character of the amp. The resistors, the capacitors, the potentiometers, the tubes, the transformers, the speakers, the voltage, everything. It’s just not anything like it once was.
 
Yes exactly!!!!! They just don't make em like they used to. Goes for the guitars as well. And its a crying shame. The art gets lost. In the old days the profession and the skills were handed down from generation to the next generation. Not so anymore. And everything is about cutting cost, and corners, and building faster, and more, and PROFITS.... Quality and skill takes a back seat to corporate goals. It sucks. Well I'm very happy for you that you have as much vintage materials as you do. I'm curious to know how you come to aquire it, and what about the rest of us who don't have draws full of old well made parts? Are there parts available any longer that match the quality of vintage one's? How are the F&T caps? the Sprauge Atom caps? Who makes great resistors?
G.
« Last Edit: January 28, 2022, 12:54:25 am by Grees01 »

Offline Grees01

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Re: Fender 5F6A bassman
« Reply #138 on: January 28, 2022, 12:57:59 am »
Grees01
When I was building my first Champ, like you, i was reading everything I could trying to figure out how a tube amp worked.I wanted to know what was happening to your guitar signal from the time it entered the input jack all the way through the amp until it hit the speaker from the OT. To help myself I drew a graphic layout drawing that helped me study it. I was having a hard time understanding how Low voltage AC and High DC voltage was traveling in the same wire at the same time. It seemed like a train-wreck in action. Then I read how Grid Stopper Capacitors blocked the high voltage DC and allowed the low voltage AC that the guitar signal is riding on to pass. Har! That was a major breakthrough for me. Attached is my drawing/Graphic Layout I did way back then. Platefire

Man, that's a really nicely done layout PF. Thanks for sharing. Yea I've got a bit of a handle on how caps allow ac voltage to pass thru but block the DC voltage from passing. It was weird to find out that both AC/DC can co-exist on the same wire. I was like "really????"
G.

Offline CascoSieg

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Re: Fender 5F6A bassman
« Reply #139 on: January 28, 2022, 10:25:27 am »
What about putting together a test-board? I find that really helpful when trying to sort out what my next project will be. There are better (safer) examples of test boards on this forum than mine, but it worked for my purposes, and probably cost me $50 in non-repurposeable parts. I've mocked up PP and SE power sections, and a few different preamps.
An exceptionally good thought. And thanks so much for sharing. To be honest, I had a very similar though in my head in the past. I never did search for it here on the forum. But in trying to figure out a design that works for you, and in the ability to tweek, and modify it sure looks like a really attractive idea. I remember those bus connectors from being a kid at my dad's shop. He had lot's of them. Is that what their called? The black mounting boards with the screws? I can't remember the correct name.
G.

I think generally they're called "Terminal Strips" ... here's a useful link: https://el34world.com/Forum/index.php?topic=15445.0

Offline sluckey

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Re: Fender 5F6A bassman
« Reply #140 on: January 28, 2022, 10:32:54 am »
barrier terminal strip
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline valvetones

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Re: Fender 5F6A bassman
« Reply #141 on: January 28, 2022, 03:13:01 pm »
Sup G’rees

Yes I’m saying they all sound as you described. I’m incredibly picky though.
To my ears, all the new fenders are harsh , ear piercing, lacking warmth, lacking depth, they are just terrible. I personally think this is because they just don’t make anything like they used to. Every single step in the chain adds to the character of the amp. The resistors, the capacitors, the potentiometers, the tubes, the transformers, the speakers, the voltage, everything. It’s just not anything like it once was.
 
Yes exactly!!!!! They just don't make em like they used to. Goes for the guitars as well. And its a crying shame. The art gets lost. In the old days the profession and the skills were handed down from generation to the next generation. Not so anymore. And everything is about cutting cost, and corners, and building faster, and more, and PROFITS.... Quality and skill takes a back seat to corporate goals. It sucks. Well I'm very happy for you that you have as much vintage materials as you do. I'm curious to know how you come to aquire it, and what about the rest of us who don't have draws full of old well made parts? Are there parts available any longer that match the quality of vintage one's? How are the F&T caps? the Sprauge Atom caps? Who makes great resistors?
G.

There were two amazing spots I visited, one giant electronics surplus store in Dayton Ohio (can’t remember the name) that was in 2010.
And a few other electronics stores, one in Odessa Texas, one in midland.

I’ll never forget the day I walked into ESI supply in Odessa. I went there to pick up a few supplies for work when I noticed rows and rows of NOS Allen Bradley carbon comp resistors, then I turn the corner and there was a whole shelf with dusty triad transformer boxes sitting there.

I talked to the owner who was happy to sell me everything I wanted for cheap. I ended up paying $20 per transformer, and I think $80 for THOUSANDs of resistors. Picked up some 6 pin and 4 pin tube sockets too so I can get my #42 tube and #80 / 5Z3 groove on.
The 80 is a four pin 5y3 and the 42 is a groovy true pentode, not tetrode as the 6v6 / 6l6 are.
The #42 really is a great little bugger. I’d take it over a 6v6 any day.

I built an amp with three 6sl7 tubes in the preamp and four #42 output tubes. It may put out 22-25 watts, but the break up on that amp is the best distortion ive accomplished yet.

Anyway, eBay has some stuff if your in a pinch, some prices are reasonable, some are outrageous, and you never know what your gonna get as far as if it’s a good part or not.
But if you haven’t been scouring at estate sales/ electronics shops for a decade, and have no luck doing so these days, than ebay is about the only place I know of for old parts.
Partsconnexion in Canada and upscale audio used to have surplus parts and sometimes they will run into new lots and sell them on their site. 
F&T and sprague are the standards these days for boutique builders. Ive used them both, they are reliable and  effective. But there are certain values they just don’t make any more.
A 16uf 450v cap is not available that I know of (for example).
And maybe I just need to look harder, but must people just through in a 20uf at 500 and call it good. And it’s prolly fine, but I can’t help but wonder how that may effect the responsiveness of the amp.
The touch sensitivity and sag and breakup responsiveness is largely a part of power supply performance.
So when someone says that electrolytics don’t effect the sound , I kinda say that the fact that the signal doesn’t pass through those caps, is really only part of the story.
Let’s say it effects the feel of the amp. Hows that.
Now I’m not saying you should use old electrolytics, unless you want to reform them, but I am saying that just like everything else, it’s not what it once was. Still good, just different.

What we can be greatfull for, is that there are companies out there trying to revive the lost art.
Western Electric for example, is making 300b tubes here in America again , with the old tooling, and they have made a huge effort to get it right.
Jupiter condenser co, is making groovy speakers and capacitors.
Weber has been at the tip of the spear, magnetic components inc, was and unfortunately not now, making transformers to vintage spec, as with mercury (which I don’t recommend) and a host of others.

So while the old recipes seem to hold the best tones, at least we have options for new parts, because some day, the last filament will burn out on an old telefunken ecc83, the last nos thordarson transformer will be thrown in the trash, etc, etc.
These companies are keeping tube amps alive by making modern equivalents , and that’s pretty groovy, even if it’s not perfect.



Offline scottcurry13

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Re: Fender 5F6A bassman
« Reply #142 on: September 22, 2022, 06:33:07 am »
Grees01

I’ve read through this whole thread and it just ends. What did you end up building?


Offline SILVERGUN

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Re: Fender 5F6A bassman
« Reply #143 on: September 22, 2022, 07:49:30 am »
Grees01

I’ve read through this whole thread and it just ends. What did you end up building?
It looks like Grees01 hasn't been on the forum since June 2022.
You might be better served by sending him a PM since that should go to his email, in case he's not looking at this forum anymore.


Offline scottcurry13

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Re: Fender 5F6A bassman
« Reply #144 on: September 22, 2022, 10:22:41 am »
Thanks.

 


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