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Vintage threads from the first ten years

Re: reissue 59 bassman-any good?

8/29/2000 2:59 AM
Peter S	Re: reissue 59 bassman-any good? Tim, You won't hear any difference between a 220uf bypass cap and 250uf cap. The tone stack of the original 5F6A came in at least four different configurations in roughly this chronological order. 1)250pf 56k slope .022 .022 2)250pf 56k slope .022 .1 3)250pf 100k slope .022 .1 4)250pf 100k slope .05 .1 The PI of the original came in at least two different configurations in roughly this chronological order: 1)10k with the bottom of the 5k presence control tied to ground. 2)6k8 tail resistor with a 4k7 resistor bypassing the presence control to ground You won't hear any difference with a 22uf filter cap compared to a 20uf.....If you actually measure the capacitance of the original Astrons, they often measured about 25uf. The original had an 8uf decoupling cap for the preamp which actually measured about 10uf. The main difference between the originals and the reissue has nothing to do with the circuit at all, since they used a circuit that actually was produced in late '59 early '60. The differences are as follows: 1) The voltages are about 35 volts too high. 2) They used cheap caps and resistors. 3) They used cheap non-interleaved transformers 4) The speakers are totally different. 5) The tubes are nothing like the originals Peter S

8/29/2000 2:59 AM

Peter S

Re: reissue 59 bassman-any good?

Tim,

You won't hear any difference between a 220uf bypass cap and 250uf cap. The tone stack of the original 5F6A came in at least four different configurations in roughly this chronological order.
1)250pf 56k slope .022 .022
2)250pf 56k slope .022 .1
3)250pf 100k slope .022 .1
4)250pf 100k slope .05 .1
The PI of the original came in at least two different configurations in roughly this chronological order:
1)10k with the bottom of the 5k presence control tied to ground.
2)6k8 tail resistor with a 4k7 resistor bypassing the presence control to ground
You won't hear any difference with a 22uf filter cap compared to a 20uf.....If you actually measure the capacitance of the original Astrons, they often measured about 25uf. The original had an 8uf decoupling cap for the preamp which actually measured about 10uf.

The main difference between the originals and the reissue has nothing to do with the circuit at all, since they used a circuit that actually was produced in late '59 early '60. The differences are as follows:
1) The voltages are about 35 volts too high.
2) They used cheap caps and resistors.
3) They used cheap non-interleaved transformers
4) The speakers are totally different.
5) The tubes are nothing like the originals
Peter S

8/30/2000 12:39 PM
Tim C.	Hi Peter, I enjoy reading your posts and have total respect for you and your thoughts. That said, I am aware that you won't hear any difference between a 250 mfd and a 220 mfd bypass cap. I was merely stating the differences between a reissue schematic and an original 59 Bassman 5F6A schematic. Fender did/does make propriatary changes to its products periodically. I have worked on only 5 or 6 original 59 Bassmans and I used to own one as well. I haven't seen the use of any other tone stack other than the one I listed from the Fender 5F6A schematic. I will conceed that Fender may have built some with other configurations but in my humble opinion the most revered and best sounding is the standard 5F6A schematic that most of us think of when you say 59 Bassman. I believe that a lot of changes that Fender did were because they were out of a particular part at a certain time and simply substituted another value. Many former Fender employees have asserted this over the years. The tone stack values, especially the slope resistor do make an obvious difference in the tonal character of the amp. I merely wanted to point that out to Joe who was thinking of getting a reissue. I have probably changed the tone stack on 15 or 20 reissues at the request of the owners because of that fact. In regard to the power supply filter section, I am aware that you won't hear a difference between a 20 mfd and a 22 mfd cap. My point was that the original had 20 mfd caps which are still available and Fender chooses not to use them. Also I didn't make this clear enough in the post but there is additional filtering in the reissue that is not on the original. The way I worded it was that there were other changes to the power supply as well. Would you consider the 5F6A as the best sounding because when you say 59 Bassman that what most will think of. The internet is so impersonal so please don't take my post in the wrong manner. If you have other thoughts than please share them as I am always ready to learn and listen. You have been very helpful here at Ampage. Respectfully Submitted, Tim C.

8/30/2000 12:39 PM

Tim C.

Hi Peter,

I enjoy reading your posts and have total respect for you and your thoughts.

That said, I am aware that you won't hear any difference between a 250 mfd and a 220 mfd bypass cap. I was merely stating the differences between a reissue schematic and an original 59 Bassman 5F6A schematic. Fender did/does make propriatary changes to its products periodically.

I have worked on only 5 or 6 original 59 Bassmans and I used to own one as well. I haven't seen the use of any other tone stack other than the one I listed from the Fender 5F6A schematic. I will conceed that Fender may have built some with other configurations but in my humble opinion the most revered and best sounding is the standard 5F6A schematic that most of us think of when you say 59 Bassman. I believe that a lot of changes that Fender did were because they were out of a particular part at a certain time and simply substituted another value. Many former Fender employees have asserted this over the years. The tone stack values, especially the slope resistor do make an obvious difference in the tonal character of the amp. I merely wanted to point that out to Joe who was thinking of getting a reissue. I have probably changed the tone stack on 15 or 20 reissues at the request of the owners because of that fact.

In regard to the power supply filter section, I am aware that you won't hear a difference between a 20 mfd and a 22 mfd cap. My point was that the original had 20 mfd caps which are still available and Fender chooses not to use them. Also I didn't make this clear enough in the post but there is additional filtering in the reissue that is not on the original. The way I worded it was that there were other changes to the power supply as well.

Would you consider the 5F6A as the best sounding because when you say 59 Bassman that what most will think of.

The internet is so impersonal so please don't take my post in the wrong manner. If you have other thoughts than please share them as I am always ready to learn and listen.

You have been very helpful here at Ampage.

Respectfully Submitted,
Tim C.

8/30/2000 1:17 PM
Peter S	Tim, I wasn't trying to critcize your post in any way. I don't claim to be any kind of so called "expert" on any subject. I just like to share what I think I know to be true from my experiences, but most importantly, I come here to learn new things. The point of my post was not to contradict what you said, because they certainly did miss the boat on some things with the reissues. I was just pointing out that there were quite few variations in those old Bassmans and I think the biggest differences in the sound ar mostly due to speakers, trannies and tubes. IMHO, Fender could have done a better job of reissuing the Bassman and still sold the amp for relatively low bucks, but I feel that these amp are overlooked by alot of people as being worthy of modding back to original specs. The places where I always start in bringing these amps up to snuff are the Trinity(speakers,tubes,trannies) You are absolutely correct IMHO that the different tone stack values will make a significant difference in tone, but I've had guys with the oddball tone stacks tell me they thought that their Bassman was a particularly good sounding one....Go Figure. I agree with you 100% that most people(myself included) find the most common variety with the 250pf 56k .022.022 tone stack to be the best sounding ones. In fact that's what Marsahll copied, and I use the very same circuit in the Kimerik amps. The tone stack would be the next place I would attack just as you suggested. As far as the electrolytic values......I think(this is just a guess) that Fender opted for the 220uf and 22uf caps, because they wanted to use cheaper IC brand caps and those are the closest values offered by that company. I guess they could have had them print shrink wrap on the caps that had the old values on it so the caps would look more authentic, but that would have cost money too. You're right though, the original values are available, and more importantly, the Sprague electrolytic caps are much higher quality than the ones Fender is using. You are also IMO correct that Fender probably used whatever they had on hand to keep the production line going when they ran out of certain component values. This was a common practice by guitar amp builders back then. Respectfully submitted back to ya' Peter S

8/30/2000 1:17 PM

Peter S

Tim,
I wasn't trying to critcize your post in any way. I don't claim to be any kind of so called "expert" on any subject. I just like to share what I think I know to be true from my experiences, but most importantly, I come here to learn new things. The point of my post was not to contradict what you said, because they certainly did miss the boat on some things with the reissues. I was just pointing out that there were quite few variations in those old Bassmans and I think the biggest differences in the sound ar mostly due to speakers, trannies and tubes. IMHO, Fender could have done a better job of reissuing the Bassman and still sold the amp for relatively low bucks, but I feel that these amp are overlooked by alot of people as being worthy of modding back to original specs. The places where I always start in bringing these amps up to snuff are the Trinity(speakers,tubes,trannies) You are absolutely correct IMHO that the different tone stack values will make a significant difference in tone, but I've had guys with the oddball tone stacks tell me they thought that their Bassman was a particularly good sounding one....Go Figure. I agree with you 100% that most people(myself included) find the most common variety with the 250pf 56k .022.022 tone stack to be the best sounding ones. In fact that's what Marsahll copied, and I use the very same circuit in the Kimerik amps. The tone stack would be the next place I would attack just as you suggested. As far as the electrolytic values......I think(this is just a guess) that Fender opted for the 220uf and 22uf caps, because they wanted to use cheaper IC brand caps and those are the closest values offered by that company. I guess they could have had them print shrink wrap on the caps that had the old values on it so the caps would look more authentic, but that would have cost money too. You're right though, the original values are available, and more importantly, the Sprague electrolytic caps are much higher quality than the ones Fender is using. You are also IMO correct that Fender probably used whatever they had on hand to keep the production line going when they ran out of certain component values. This was a common practice by guitar amp builders back then.

Respectfully submitted back to ya'

Peter S

8/28/2000 5:56 PM
Peter S	Steve, It absolutely would be better and cheaper to build one from scratch. The last one I built ended up costing around $500.00 for materials if I remember right. I use only the highest quality materials I can obtain when building though so it could probably be done for less money. This doesn't take into account the time spent, however, building the amp is the fun part. I would have reccommended building it from scratch, but I've been ragged on before about suggesting that, because I guess some people feel inadequate when it comes to building amps from scratch. Seriously though, it would be very easy to get a prefab Bassman replacement chassis, and cab, a good quality fiber eyelet board(why use a Hoffman board when you can build the real deal for under $40.00 and have good quality caps and resistors mounted on the original style fiber board with the identical layout as the original) some pots,caps,resistors, switches, cloth wire, speakers and go to town. I know I left out a few incidentals, but they are no big deal. This is absolutely the way I would go. Peter S

8/28/2000 5:56 PM

Peter S

Steve,
It absolutely would be better and cheaper to build one from scratch. The last one I built ended up costing around $500.00 for materials if I remember right. I use only the highest quality materials I can obtain when building though so it could probably be done for less money. This doesn't take into account the time spent, however, building the amp is the fun part. I would have reccommended building it from scratch, but I've been ragged on before about suggesting that, because I guess some people feel inadequate when it comes to building amps from scratch. Seriously though, it would be very easy to get a prefab Bassman replacement chassis, and cab, a good quality fiber eyelet board(why use a Hoffman board when you can build the real deal for under $40.00 and have good quality caps and resistors mounted on the original style fiber board with the identical layout as the original) some pots,caps,resistors, switches, cloth wire, speakers and go to town. I know I left out a few incidentals, but they are no big deal. This is absolutely the way I would go.

Peter S

8/28/2000 5:06 PM
Deltablues	I've owned both the reissue and a real 59 bassman. And for a period of time before selling the reissue, I had them both side by side for comparison. Definitely a difference in tone... The real deal was warmer, had more bottom end, was more touch responsive, and had a lively yet not as harsh treble reponse. (I still have the real 59). That said... A "used" reissue bassman is a great bang for the buck amp. They can be had used for $400-$450. And with a simple change to NOS tubes and a rebias, they are also a great bang for the buck tonewise. But I agree with the poster that said they're not worth investing $600 or $700 into unless you're just doing it because you want to tinker. Because you're never going to get someone to give you $1000+ for a reissue even if it does have a hoffman board and reissue Jensens in it. If you have $1000 to spend and you REEEEEALLY want a tweed bassman, use it as a down payment on a boutique or a real one that needs some TLC. At least that way, the resulting amp will have some resale value if you ever decide to sell it.

8/28/2000 5:06 PM

Deltablues

I've owned both the reissue and a real 59 bassman. And for a period of time before selling the reissue, I had them both side by side for comparison.

Definitely a difference in tone... The real deal was warmer, had more bottom end, was more touch responsive, and had a lively yet not as harsh treble reponse. (I still have the real 59).

That said...

A "used" reissue bassman is a great bang for the buck amp. They can be had used for $400-$450. And with a simple change to NOS tubes and a rebias, they are also a great bang for the buck tonewise.

But I agree with the poster that said they're not worth investing $600 or $700 into unless you're just doing it because you want to tinker. Because you're never going to get someone to give you $1000+ for a reissue even if it does have a hoffman board and reissue Jensens in it.

If you have $1000 to spend and you REEEEEALLY want a tweed bassman, use it as a down payment on a boutique or a real one that needs some TLC. At least that way, the resulting amp will have some resale value if you ever decide to sell it.

8/28/2000 10:39 PM
Richie{~}==:::	If you were going to redo it anyway.. why not find a used one.. real cheap ..maybe one that had problems, Strip it and build it from scratch.. at least you'd have half of it pretty much done. Might be a cheaper route.. than rebuilding a brand new one.. Richie{~}==:::

8/28/2000 11:15 PM
Lee M.	Used Victoria Bassman copies are fetching $1100-1200 bids on Ebay. Probably a better way to go than paying $500 for a Fender then spending another $500 to get it close to a boutique copy. The "real" fake thing will hold its value better. Lee

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