The harm in 'upgrading' components?

[duriehill]

Thanks all for the advice 8)

It really has given me much more insight. I've a better understanding and approach to selecting components and the reason for selecting a component based on it's role/characteristics in a circuit.

This post specifically had in mind my 102 build, which may be born by the end of the year (I will post). I've studied this amp and HAD's choice of components and maybe the reason behind his choices.

[Kassie]

The way I look at it.

Guitar Amps are different from HIFI amps. A guitar amp is indeed an amplifier. But it's also a tone generator (wow I must be some kind of genius). A typical HIFI amp needs to reproduce as clear as possible, as defined as possible. Whenever a Hifi amp adds a bit of character of it's own that people may describe as 'pleasing'. They call that 'Euphonic'.

So in selecting components for a guitar amp... you can use HIFI components.. (Usually components of high quality). For instance.. Silver Mica capacitors, or very expensive filter caps, or a linear OT, or overspeced transformers or HIFI speakers....

Actually for a guitar amp to sound good, builders often choose to stay away from HIFI principles. (Big power filtering, maximum headroom, no clipping, high quality components). If we move on to suitable components for a guitar amp.. they are often outdated quality, and they add character to a sound. (Dumble used ceramic disc caps, or a few carbon comp/film resistors, carbon pots instead of conductive plastic). The typical transformer choices etc.

The 1% resistors on the board are cathode resistors, they carry no signal but bias the gain of the tube... I strongly doubt Dumble used 1% resistors because that bias comes critical and thus hearable (let say 1.45k or 1.55k). I strongly believe he used 1% low noise resistors because he wanted to add the least amount of noise into the circuit.
The same might be said for some metal film choises for the anodes. Possibly a higher gain circuit might benefit more from lower noise components. But it is said that carbon film/carbon comp actually produce a distortion that is somewhat beneficial, at the cost of some noise.

So I believe it is not soo much the precise measurement of the resistor, as much as it is how it contributes to the circuit (tone versus added white noise). You can try to put higher quality components (Silvercoated wire instead of copper, redo the power supply for lowest ESR or stiffen it up... replace every resistor with Metal Film, use a HIFI OT for lots of bass and treble defenition, plastic conductive pots etc.) But will it necessarily sound better? I don't think so.

[Mark]

Try recording the amp before and after a change. I experimented with caps in a Champ, I had all the caps set up on tag strip and switched between them. I used a CD player to provide the signal, to my surprise all the caps sounded the same. Thinking I missed something I recorded the examples into the computer and cut and pasted them in such a way that I would hear one the the other cap with no break. The result was still no change.

I did try simply playing through the amp and I found I was playing the passages subtle different every time which made it seem like differences between caps.

[renshen1957]

On the other hand maybe the xicons gave the amp a bit of bite or clarity and countered some darkness or softness from somewhere else and HAD used them intentionally. I doubt he gave much of a a hoot, but only HAD would know for sure. I'm still a paint by numbers guy and learned that stringent cloning can get you within a hair of the real thing. But I got there the hard and expensive way.

Hi,

Xicon to my knowledge is a trade mark owned by Mouser. I don't think there is a "Xicon" Factory as such. A search at the USPTO list G & S Components, and Mouser. I blissfully ignorant attempted a purchase of Xicon transformers in China, figuring there was a factory there. The Chinese "Xicon" referred me back to Texas.

Most likely the the Xformers are made in Ningbo, China and Mouser stamped their name on them. All I know was the build time and shipping time to Texas from either China or Taiwan, ROC made sense especially if other components were to be shipped to fill up a cargo container.

Xicon resistors today aren't the Xicon resistors HAD used unless HAD built an amp since the RoHS no lead standards came in. Mouser has owned the TM since 1988. But I don't see any factory in Mansfield TX.

HAD and Trainwreck's Fischer have many parallel aspects in their careers. I won't go into their bios, just that both had experience in Amp repair, both used components as they saw them, etc. Both are noted for building Amps that are basically to a general form. TW used different parts and the amps were unique (even to the use of names). HAD amps are basically custom jobs for a particular player. Similarities between the amps, yes, but not a production line of identical component values, etc.

I am of the school that HAD used what was available and used it where he knew it made the difference.

Mepco resistors or DaleRN65 Metal films? I scene both on schematic/layouts. One is to be found in surplus, the other is still made (maybe RoHS now), but what if either was picked up from Military surplus from an electronics store (these still exist especially in cities with Military bases nearby).

Taiwan Alpha pots (!). Maybe he liked how it was spec'd or the resistance log was right, but more likely it was available from Radio Shack, back in the day when Radio shack carried more parts and was less concerned about selling Cellphones plans to its customers.

Alpha is all over the map on products it offers. And gee whiz some of the quality leaves something to be desired. I do not like the feel of the pots rotation. The word Alpha stamped on the back of a pot case doesn't mean it's the same as HAD used. Same thing is true with Bourns pots, all purchased from China. Taiwan Alpha Pot may own stock in factories in Big China. And since China/ROC sell world wide, Alpha pots will be RoHS.

I have seen a number of components become obsolete, only to be replaced by newer and more expensive RoHS lead free versions. But I don't think I will ever go to lead free solder. X-Box found out the hard way, so have other products that went lead free and suddenly had brittle solder that did survive the rigors (or abuse) of shipping.

A analogy I draw about cloning is with harpsichord building. You can copy write down to the last detail, purchase similar wire and wood (but NOS wire and NOS 300 year wood doesn't grow on trees) and the end result doesn't sound exactly the same as the original. The builders skill is involved, yet one builder had written some time ago that we copy only what we do not understand. If you understand the whys, you can go on and build a better instrument, closer to what the tone may have sounded several hundred years ago. So it isn't just 59 bassman repos that require Mojo or Voodoo parts.

If Takman or Koa Speer/Kiwame CF had been available (and the same or lesser price) to HAD he may or may not have used them. But since he wasn't/isn't concerned about building production line amps with a deadline, HAD has the luxury to try parts, etc, or from experience knows exactly what he wants (an individual amp).

Or HAD maybe like a guitar builder I know. Crusty, temperamental, moody (to work for), and also imbued with the flip side of the coin, only builds when he darn well feels like it or needs the money. When he does build, the results are breathtaking. And he uses quality run of the mill parts. Go figure.

Best regards,

Steve

[talbany]

Steve
Here is how I look at it!!
I too used to think HAD used what he had available at the time..I also believe he had his standards and stuck with them..He might have even had a favorite brand name or a certain part he preferred to achieve a certain sound..There might have also been times where he had to make some compromises due to the availability as with all amp makes have..In general there is a common thread that runs through most Dumbles (the ones I have seen) for me paints a clear picture of what he thought gave him the sound he was hearing in his head,or to quote him "when the air becomes electric"..
These include 1% MF RN series (and in some cases KOA's) for plates and cathodes,Carbon film's (Draloric family) signal path, CTS (Fender style 2-35) Pots in the key spots (not Alpha's),PS series caps,Fender Twin Iron (in 6L amps), TVA Sprague Atoms for filters in the Standard PS and a mix of caps in the Precision,..Things like coax,bypass caps, all seemed to change with each generation..I constantly hear people say that each Dumble amp is built custom for that customer and to some extent some were but IMO there were a very few..Some tweaks I've noticed might be a different slope resistor or different value Drive and level controls and bypass caps...These amps are few and far between and generally stuck to that generation's design..Look at Ry's Boarderline amp..One would think that amp would have certain alterations in the design to accommodate a wonderful slide player like RY,and that's a stock low plate classic (with added Trem)...Not to beat a Hoarse here just how I look at it!!..Thanks for the info on Xicon..I personally never cared for either there Filter caps or resistors Xicon=Cheap

All The Best!!

Tony

[ToneMerc]

Steve
Here is how I look at it!!
I too used to think HAD used what he had available at the time..I also believe he had his standards and stuck with them..He might have even had a favorite brand name or a certain part he preferred to achieve a certain sound..There might have also been times where he had to make some compromises due to the availability as with all amp makes have..In general there is a common thread that runs through most Dumbles (the ones I have seen) for me paints a clear picture of what he thought gave him the sound he was hearing in his head,or to quote him "when the air becomes electric"..
These include 1% MF RN series (and in some cases KOA's) for plates and cathodes,Carbon film's (Draloric family) signal path, CTS (Fender style 2-35) Pots in the key spots (not Alpha's),PS series caps,Fender Twin Iron (in 6L amps), TVA Sprague Atoms for filters in the Standard PS and a mix of caps in the Precision,..Things like coax,bypass caps, all seemed to change with each generation..I constantly hear people say that each Dumble amp is built custom for that customer and to some extent some were but IMO there were a very few..Some tweaks I've noticed might be a different slope resistor or different value Drive and level controls and bypass caps...These amps are few and far between and generally stuck to that generation's design..Look at Ry's Boarderline amp..One would think that amp would have certain alterations in the design to accommodate a wonderful slide player like RY,and that's a stock low plate classic (with added Trem)...Not to beat a Hoarse here just how I look at it!!..Thanks for the info on Xicon..I personally never cared for either there Filter caps or resistors Xicon=Cheap

All The Best!!

Tony

Tony we are both on the same page and when he ran out of Pihers he started to use Draloric. As I've said before there are patterns.

TM

[renshen1957]

Steve
Here is how I look at it!!
I too used to think HAD used what he had available at the time..I also believe he had his standards and stuck with them..He might have even had a favorite brand name or a certain part he preferred to achieve a certain sound..There might have also been times where he had to make some compromises due to the availability as with all amp makes have..In general there is a common thread that runs through most Dumbles (the ones I have seen) for me paints a clear picture of what he thought gave him the sound he was hearing in his head,or to quote him "when the air becomes electric"..
These include 1% MF RN series (and in some cases KOA's) for plates and cathodes,Carbon film's (Draloric family) signal path, CTS (Fender style 2-35) Pots in the key spots (not Alpha's),PS series caps,Fender Twin Iron (in 6L amps), TVA Sprague Atoms for filters in the Standard PS and a mix of caps in the Precision,..Things like coax,bypass caps, all seemed to change with each generation..I constantly hear people say that each Dumble amp is built custom for that customer and to some extent some were but IMO there were a very few..Some tweaks I've noticed might be a different slope resistor or different value Drive and level controls and bypass caps...These amps are few and far between and generally stuck to that generation's design..Look at Ry's Boarderline amp..One would think that amp would have certain alterations in the design to accommodate a wonderful slide player like RY,and that's a stock low plate classic (with added Trem)...Not to beat a Hoarse here just how I look at it!!..Thanks for the info on Xicon..I personally never cared for either there Filter caps or resistors Xicon=Cheap

All The Best!!

Tony

Tony we are both on the same page and when he ran out of Pihers he started to use Draloric. As I've said before there are patterns.

TM

Hi Tony and TM,

I am in total agreement, you're tweaks comment put what I was attempting to type in proper context. The patterns is what I have observed, the details you both listed.

Dave Funk in his only amp book (regrettably), wrote on using metal film for Cathodes, and also his fondness for 3k3 resistors for cathodes. I see this is a popular value amongst other builders.

Another author (I can't think of who), commented on using metal films on plates and cathodes, but used carbon films in audio path to warm up the sound (more vintage sounding). He wrote on Hi Fi amps and old Am Radios.

Best regards,

Steve

[talbany]

This is as close as I can get..102

Yellow Sprague Atoms TVA
NOS Mallory PVC's
Pihers in signal path
Fender CTS Pots
KOA on plates cathodes
Sylvania 7581


Show us yours if you have them..

Tony

[ToneMerc]

Or HAD maybe like a guitar builder I know. Crusty, temperamental, moody (to work for), and also imbued with the flip side of the coin, only builds when he darn well feels like it or needs the money. When he does build, the results are breathtaking.

Steve

I found that out 25 years ago and I know the good, the bad and the ugly. So I certainly believe there's a certain amount of that. Nevertheless, with the internet lore if he really wanted to chase a dollar, things could have been so different for him. In the end I have to admire a man that has the balls to do things his own way, all the time.

TM

[ToneMerc]

Show us yours if you have them..

Tony

For a 2nd gen signal board clone you can't get much closer than this.

100% era/composition correct Electra MF7C on the plates, MF6C on the cathodes.

100% Piher carbon films in the signal path

Era correct/composition correct Sprague orange drops(except that Pres film cap)

Sprague TE caps on the cathodes, had era correct yellow Atoms on hand but didn't use them because they were +25-30%.

[talbany]

Mike
Awesome..
You come about as close as anyone I have seen..I too have some yellow Sprague bypass 5uf TVN but they read more like 10uf on the meter..Would love to get some of those TE's although the Nich's do a decent job
2nd gen amps are very cool!!

Nice work

Tony

Show us yours if you have them..

Tony

For a 2nd gen signal board clone you can't get much closer than this.

100% era/composition correct Electra MF7C on the plates, MF6C on the cathodes.

100% Piher carbon films in the signal path

Era correct/composition correct Sprague orange drops(except that Pres film cap)

Sprague TE caps on the cathodes, had era correct yellow Atoms on hand but didn't use them because they were +25-30%.

[ToneMerc]

Would love to get some of those TE's.
Tony

Thanks Tony and I"ll sent you a fresh 5uF set then.

Mike

[CHIP]

Would love to get some of those TE's.
Tony

Thanks Tony and I"ll sent you a fresh 5uF set then.

Mike

Are those TE's no longer available from retailers? I used to be able to get them from Mouser just a few years ago.

Just looked , they have still carry them.

[talbany]

Would love to get some of those TE's.
Tony

Thanks Tony and I"ll sent you a fresh 5uF set then.

Mike

You are too KIND!!
Glad I didn't goop it.

Tony

[67plexi]

Cool looking amps Tony & TM.
I must be lost I can't find the overdrive. But the resistors are spot on.

Steve.