I wasted no time after finishing the Weber 5E5A kit to start my BYOC Tweed Royal kit.
I couldn't find much in the way of reviews for the kit but I thought the concept was really neat. My original plan was to wait until I was finished the Weber to even purchase it but July's 25% off sale was too enticing to say no to.
I ordered my kit with no speaker and no tubes. I had new JJ's and plenty of loose 12" speakers to pick from. The discount only applied to the kit and not the tubes or speaker.
One thing that differentiated this kit from the Weber kit is that there were instructions. This kind of gave me more focus and was incredibly detailed about things such as lengths of wire needed.
Another thing worth noting is that the transformers are all made in the USA. The bulk of the resistors are carbon comp (for that old school mojo), the caps are Sprague, Switchcraft jacks, and the board is a turret style board instead of an eyelet board (as found on most Fender amps). The wire the kit came with is also vintage style pushback wire which is a blast to work with! One thing that I was a bit puzzled by was that one of the color wires provided was not pushback wire but was actually cloth covered normally insulated wire. After using pushback wire, I never want to use anything else. The only negative I could come up with immediately was the use of Alpha pots. I understand that they have a selection that most other manufacturers can't compete with, but I am just not a fan. Additionally, my PT came with dented bells. Somebody probably dropped it before it was ever packed. The kit came well packed and the damaged didn't look very severe so I figured I'd try the kit and if I had problems I'd worry about it then.
I followed the instructions building up the board first. This process went very quickly. I would have been a little happier if the turrets had a slightly larger opening in them so that I could fit some of the thicker lead parts in without difficulty. Some of the turrets didn't want to take on the solder very easily either. If I had known, I would have cleaned each of the turrets with some coarse sandpaper first. Yes, it would have been a lot of work, but it would have saved me even more frustration.
Next I built up the chassis. This was mostly just putting the sockets (which like the Weber kits are also ceramic), transformers, and pots into place.
As I mentioned in my last entry with the 5E5A, it seems like heater wiring is just an afterthought, but I like to run my filament line while nothing else is in the amp to get in the way and then tuck the wires into the corner of the chassis. So needless to say, I skipped ahead to the last instruction and ended up using some of the twisted wires from the Pro build to run the heaters instead of the solid pushback wire they included.
Sorry BYOC, my heater wiring looked nicer than the picture in the instructions. That kind of brings me to another point which may be jumping ahead a bit. Some of the instructions were not done in the most logical order. This meant going back and doing things that you could have done earlier as well as having to solder connections that were made underneath of prior connections which isn't so easy.
Another "quirk" I found was that some of the wire colors change in the instructions from white to yellow or yellow to white. Not a big deal. At least one wire is referenced as though you had soldered it to the turret board and were making a connection to one of the sockets. I had triple checked the instructions and this wire was never mentioned prior. Not a big deal either. What IS a big deal is that a lot of the lengths of wire that I carefully measured out as per the instructions were more than just a little short. My advice, if you are building this kit, tack on at least an inch to each run of wire coming off of the turret board. Not all of them are short, but they give you plenty of wire so don't be stingy with it. I just assumed (wrongly) that it was carefully measured and was done for good lead dress.
What I ended up with was a lot of reworking and wasted wire. Most of the wasted wire was salvaged for other steps that required short pieces of wire to act as jumpers.
Possibly the most frustrating part of this kit was that some parts that are inherently designed to accept solder refused. I had a serious fight with the fuse holder. You would expect that the fuse holder would take solder as it is meant to. I had to "unsolder" (as though my solder wasn't literally just dripping off of the fuse holder) the wire and go over the surface with coarse sandpaper. Then it finally stuck. What is weird is that only one of the 2 terminals on the fuse holder gave me any trouble. I also mentioned how some of the turrets themselves weren't so good about accepting solder. I used a small mill file to score the surfaces and get the solder to flow. And both of these were nothing compared to the back of the 2 volume pots which were grounded with a jumper lead. I could not get solder to stick to them. The instructions warned that there was a coating added to the backs of the pots to prevent soldering to them. WHY!? That is the most bizarre thing I have ever heard. I ignored this advice (quite foolishly) and quickly found that the pots were indeed coated with something that made the solder run right off of them. Again, WHY!? I tried scoring them with sandpaper the same way I had scored the fuse holder and while that helped, it didn't eliminate the problem. My solder joints to the back of the pots looks worse than my first time out with a soldering iron on my friend's crappy guitar. Not a proud moment for me then or now.
I've never run into anything like that before. If I had to do it all over again, I'd take that note a little more seriously, and really dig in with the sandpaper. Don't even bother with steel wool. It isn't abrasive enough to remove this heavy film of god only knows what. I don't think I have ever swore so much at a piece of electronic equipment (besides the computer of course) in all of my life.
After getting the entire kit together, I had to decide what speaker I was going to put in the amp. I was originally going to use an old Jensen C12R. I have a set of 4 and this was the right sort of wattage for that speaker. I also had a modern Jensen P12R that came in a broken Fender Musicmaster amplifier project. In the end, I decided that I would rob the Musicmaster of the P12R and put in a C12R.
This turned out to be a mistake that would cost me a bit of time.
I wired everything up and loaded the pilot light bulb, fuse, and tubes. I plugged the amplifier in and grabbed my Jap Strat. I kicked it off of standby and into SE. The volume was VERY low and everything was fuzzy. It sounded cool, but it didn't sound right. I turned all of the controls and they seemingly did what they were supposed to, only at low and fuzzy volumes.
Something was definitely wrong.
I turned off the amplifier and took it back to the shop. I didn't even screw around with taking it apart. I just disconnected the speaker and tried the 15" from the Weber 5E5A. Immediately the amplifier began behaving exactly like I expected it to!
I played with all of the controls and honestly, this amp could have just been a champ and I'd have been happy. The tone control is nice I guess, but it sounded good with it off and the cut control is a nice feature too, but again, it sounded plenty good off. The Single Ended and Push Pull modes were the big selling point for me and yes, it is a little different tonally as well as volume wise. But is it all that much different? Not really. I love how the amp sounds, but I guess I'd have been content with a Champ.
The next day I woke up early in the morning and removed the bad P12R and installed the C12R. 30 minutes later, I had the amp completely back together and ready for testing again. This time it made some crackling noise intermittently. I shut the amp down. Apparently, during the course of disassembly and reassembly, I had bumped the preamp tubes in their sockets. The rectifier and power tubes had been removed but I left the preamp tubes in place. I thought I'd save myself some time this way but I ended up having to remove them to reseat them anyway. Let this be a lesson about trying to save a few minutes.
After the tubes had been reseated, I turned the amp on again and this time everything worked as it was supposed to with no obnoxious crackling or noise. The amp does have a small hum about it which could be the layout or the fact that I primarily tested it in SE mode. The push pull setup should remove some of the noise due to the noise cancelling attributes it has.
The noise is not all that loud and like most things, I am probably nitpicking. The amp sounds really good. I am still happy with a single channel and the volume control though. Maybe with a hotter guitar the cut and tone controls would be more useful but I was using my strat with an underwound neck.
One side note about the basic circuit (ignoring the fact that this amp is like a Swiss army knife) is that I can completely see why Fender moved away from this style of circuit and into fixed bias amps. While the purpose of this amp (for me anyway) is to get a nice breakup at a relatively low volume (and it does it well), the amp has almost no headroom. It breaks up very early and has enough gain to drive a much larger amp. Even in the PP mode, the amp doesn't gain all that much in the way of headroom. This is a nice thing for those of us who want a cranked amp sound without a visit from the local police department, but Obtaining 4-12 clean watts out of this amp is not really likely.
To conclude this review, I'd like to say that the kit sounds really good and it may be exactly what you are looking for if you like gear with lots of options to tweak your sound to the smallest detail. But if you are more like me, you are going to find a lot of the options gratuitous. This isn't to say that I don't like the amp. I really do. I think it sounds great (as I've stated at least 4 times now), but I also know now that I'd have been totally content without all of these options.
Sunday, August 11, 2013
Sunday, August 4, 2013
Built a Weber 5E5A Pro Kit!
I just finished a Weber 5E5A kit yesterday (8/3/2013) so I will post a review of my process and some of the things I liked and disliked about the kit and the experience in general. This may come off as a bit disorganized because A) it is and B) I am 3 beers into relaxing on a Sunday.
I ordered the kit and waited the 3-4 weeks as the Weber site indicates. I chose a custom green covering with a green pilot lamp and wheat grill cloth. Being able to completely customize your cabinet at little (if you go crazy with the options) to no extra (if you choose standard options) is a nice feature.
I also chose to get the Weber 15" alnico speaker with it.
When the kit arrived, I was surprised at how light it was. I am not going to say it isn't heavy, but it isn't as heavy as a similarly sized amp.
The cabinet looks good. Some of the tolex work could be marginally better and the cabinet's joints could certainly be tighter, but honestly, I am nitpicking here. The cabinet looks sharp and I have no doubt that it is structurally sound and infinitely nicer than virtually anything on the market from any of the mass produced companies. It is a solid pine box.
The speaker came premounted in the cab. I didn't check the nuts that hold it to the baffle. If any sort of rattling develops later, that'll be the first place I look.
I like the a la carte options with the kits. I don't know what type of tubes Weber supplies with the kit, but I opted not to have tubes or a copper cap rectifier supplied. I have plenty of 5U4's and other common tubes around. That saved me a few bucks which covered the additional shipping charges which were more than fair.
The kit portion of the amplifier comes with no instructions other than a schematic and a wiring diagram you can download from the Weber website. I printed both of these on my black and white printer as well as the transformer wiring diagram.
The power transformer comes with way more taps than you need. In particular, it has a lower voltage secondary in case you opt to use a solid state rectifier instead of a a tube rectifier. I thought this was a neat option but ultimately decided on a tube rectifier. Could I picture a Fender clone any other way? Absolutely not!
Being that the kit had no instructions, I just kind of soldered the parts into the eyelet board and left very generous lengths of wire where appropriate. This isn't the most resourceful way to assemble an amp if you are short on wire, but it allows for a lot of screwing up.
Shortly upon getting started, I noticed that I was missing a preamp tube socket. I contacted Weber and without question, the sent me a socket. I truly appreciate that! It is why I will continue to shop Weber. Customer support goes a long way with me!
While mounting the transformers to the amp, I noticed that one of the transformers is meant to be mounted at a 45 degree angle. I wasn't crazy about this arrangement because the mounting hardware interferes with the board laying flush against the chassis. I drilled new holes and mounted the choke more in line with what Fender would have done. To be honest, I am not even sure whether the choke or OT was supposed to be mounted at the angle. Both ended up mounted like Fender did on their Tweed amps. In order of how they were mounted, I went PT, OT, Choke. It made the most sense with the wiring.
I actually bothered to look at tweed chassis photos just to see what Fender did. It is worth noting that I put the nut end of the bolt inside of the chassis and had I put the head of the bolt into the chassis and the nut on the outside, I could have stuck with Weber's 45 degree angle transformer with no issues.
While I was modifying the chassis, I moved one of their wire through holes to another part of the chassis that was more in line with how the wiring diagram looked. I used a cold chisel to debur the hole which worked really well. I should have moved both of the wiring through holes, but I'll have to remember to do that next time.
The other through hole sits right under the board and lifts it which doesn't hurt the board any, but would have made things easier when mounting the board or moving wires from the OT and choke to their proper connections had I just moved the hole and inch or so.
I also would move the transformers further away from the PT so that I could stick an adjustable bias pot in. The amp is a non adjustable fixed bias. I don't really have a problem with that, but having the option to adjust the bias would have been cool if I wanted to stick a 5Y3 and a couple of 6V6's in. I'm sure I'll be able to figure some other way out when it comes up.
Weber supplied wire with the kit. It is a cloth covered type that is not a pushback wire. It is just a cloth sleeve over a normally insulated wire. It was easy to strip though (which some cloth insulation is not) so I cannot complain. The wire was all 22 gauge. Some of it was stranded and some of it was solid.
I do no like using solid wire as much as stranded. It isn't as durable, which may be a non point in the case of the inside of an amplifier where the wire isn't being moved so much. But it also doesn't have the same current handling abilities. I used all of their stranded wire and stuck the solid wire in my "box o' wire" where all of the spare bits go.
I've noticed a lot of amp kits and even professional amplifiers give very little discussion to the filament wiring aspect of amplifiers. If you look inside of a blackface Fender amplifier, it looks like the heater wire was literally the last step...almost like it was an afterthought. Morgan Jones has a wonderful book Valve Amplifiers which is really worth obtaining and reading if you are into building and designing amplifiers. It gets technical rather quickly, but also goes into a lot of theory which other authors don't mention at all or give a very brief explanation of.
He suggests running the heater wiring first because if it is done right, it will never need to be run again and only stands to get in the way should other work need to be done. Twisted wire should be used and pushed into the corners of the chassis for optimum hum cancellation. I tried using some of the cloth covered wire for the heaters but it just knotted when I attempted to twist it. I am lazy, so I took two equal lengths of wire and locked one set of ends into my bench vise and the other end chucked into my cordless drill. Then I slowly pulled the trigger while holding the wire taught. With the cloth wire it was just a mess of knots. I used some loose 18 gauge wire I had around and it twisted perfectly. Unfortunately, the 18 gauge wire was simply too large to get into the 9 pin miniature sockets so I went with 22 gauge wire for the preamp sockets and 18 gauge wire for the power amp sockets. If I had 20 gauge wire, I'd have used that for the preamp section. Again, it'll be on my to do next time list. Maybe I am just going overkill anyway. I've been accused of it before.
I also used some 600 volt 22 gauge stranded wire I had when I ran out of the wire the kit came with. Again, I probably had enough wire had I used the solid core wire. The 600 volt wire differs from the 300 volt wire in that the insulation is much thicker. This will keep any arcing through the insulation at bay.
One thing that I thought was really screwy was that the resistors were all metal film resistors with 5 band color codes. I literally double checked every resistor with a meter since I am used to the normal 4 band color code.
Some of the resistors were also different wattages. I really wanted to use all 1 watt plate resistors, but a lack of preplanning prevented me from doing that. It wouldn't have been any more difficult. Some of the resistor leads were unable to traverse the distance between the eyelets and have to be soldered onto the leads of other parts. I am not a fan of this practice, but impatience got the better of me. I could have ordered parts with the correct leads or wattages I wanted but I just sort of used what I was given. I am sure the 1/2 watt resistors will hold up just fine. Given the great number of Fender amplifiers from the 50's with the original resistors, I'd say I have nothing to worry about...but I just like to overbuild everything!
The caps that came with the kit were Weber's caps. I have used them in the past. They are very inexpensive and work well. I have no complaints.
The pots are kind of cheap. I don't know that anybody makes a modern pot that is all that good though. Most of them have tapers which are not as good as old pots. It is apparently cheaper to make pots with two linear taper tracks that approximate an audio taper than it is to make a pot with a true audio taper. This leads to all kinds of weird performance.
I also didn't like that Weber doesn't supply a second nut for mounting the pots. I wanted the pots as low as they would fit onto the chassis so that the knobs didn't have an unsightly gap between them and the faceplate of the amp. I had some loose nuts in my random junk parts so I was able to make that work.
You have to be careful when you tighten the pots and other parts onto the chassis faceplate. The chassis has a very nice and heavy chrome with white letters that are silk screened on. The lettering can be a bit fragile when you challenge it to a duel with a wrench. I saw a post online about somebody using some sort of tape to protect the lettering which in turn pulled the lettering up. Just be careful when you assemble it and you won't screw up your lettering. Or maybe you don't care and think it just gives it character?
The knobs that Weber provide are kind of junky. One of them had a set screw that was missing the head. I used a bunch of salvaged old stock knobs instead. If the last knob had a working set screw, I would have used the ones provided.
You are also given two wood screws (or are they self tapping sheet metal screws?) to mount the board to the chassis. The holes they are to go into are much too small. I had to enlarge them. I also had to run various other screws through the holes to get them even started. One of the screws sheared off at the head which required me to use some linesman pliers to remove. A bolt and a nylon standoff would have been much easier and just as secure. Again, impatience got the better of me. Next time I'll go to home depot to get the standoff and bolts. Instead I just forced a bunch of metal screws through until I found ones that fit the way I liked.
The amp goes together really easily if you can read a wiring diagram. The only thing I had major troubles with was the grounding scheme. There are lots of ground points referenced throughout the amp and most of them go to either the heavily chromed chassis or the brass grounding plate.
Neither are easy to solder to. I have a heavy duty 60 watt iron (in addition to the more surgical regulated iron I use regularly) and it barely was able to get anything to stick to the brass plate. I didn't even try to make it stick to the chrome.
My understanding is that the chrome finish is toxic if you bring it to high temperatures or if you removed it (and subsequently breathe it in) to solder to the steel beneath it.
The Weber chasiss did have one interested feature. There is a copper stud welded to the chassis near the PT. I soldered a terminal strip to the copper stud. Then I connected all of the grounds to this copper stud/terminal strip setup.
For the cathode of the power tubes, I ran them to this terminal strip with a 2 watt 1 ohm resistor so that I can measure the combined cathode current should I ever get around to putting an adjustable bias setup in place. Since I run matched tubes, there shouldn't be any problems with one tube drawing more current than the other and giving false readings.
For the pots and jacks, I gave them a ground bus which was just a solid piece of wire run along the backside of the pots. I then grounded the 5 connections from the board to this bus. One end of the bus was connected to the grounding terminal strip. I am sure I should have isolated the input jacks to prevent ground loops, but I have seen Gibson amplifiers with this exact setup and no concerning noise issues.
All of the wiring kind of came together really fast after the board was wired up and the sockets had the heater wires run. I was actually unprepared for the moment when it was all done.
I had the power and preamp tubes but no rectifier tube. I loaded the JJ tubes in and rummaged through my many boxes of old tubes and found a loose GE 5U4. I was in business!
I plugged in the amp and kicked the power switch on for the first time. The pilot light was bright and there were no blown fuses. Surely, this was a good sign!
I grabbed the Kramer Baretta I have been working on for a friend and plugged it in as it was the closest guitar. I'm actually more of a Tele/Strat/Jazzmaster player. I used a cord I had made out of some Belkin cable wire which is really low in capacitance and resistance. At 10 cents a foot, the switchcraft ends are the most expensive part of it.
I flipped the standby switch and heard what can only be described as the rush of life into the amplifier for the first time. I'm sure Dr Frankenstein felt the same way!
All of the knobs (except the volumes) were set to 5. I did a check of all of the controls and inputs doing what they were supposed to.
One thing that really surprised me was how absolutely loud this amp is! I felt it deafening me even at 2 (out of 12)! This goes back to the pot tapers I mentioned earlier. There is some hiss from the amplifier that could be caused by lead dress (I didn't use any shielded wire) or maybe it is just inherent in the circuit or tubes. The noise definitely went away as the treble pot was adjusted.
It isn't a loud hiss by any means and I have no desire to track it down. I have owned much lower wattage amps that made much louder idling noises.
The presence control is interesting on the amp. I expected it to make the amp brighter as I turned it up. This is what typically happens anyway. What actually happens on this amp is it just gets more raw as the presence control has a large .1uf cap on it which allows almost all of the frequencies to bypass the negative feedback loop. I played with that control the most. It is subtle and I'm sure it'll do more as the amplifier is turned up, but at low volumes, it is noticeable and I think I actually like the control set more toward 1 than 12. After I get to know the amplifier a little better, I may change my tune and come up with favorite settings.
Overall, I was really impressed with the Weber kit. It is by far the cheapest kit in the internet and probably the most versatile in terms of what you choose to get with your kit. Some of the things I didn't like just come down to personal preference. I know it seems like I had a lot of trouble assembling the kit or had problems with most of the parts, but it actually went together very smoothly and I spent more time thinking about what I was going to do than doing it. I also like the ceramic sockets that they supply. The OT has 2, 4, and 8 ohm taps which is also nice. I'm not going to say that this kit is for everybody. If you don't know how an amplifier should go together or this is your first kit, you are in for a hard time. There are no printed step by step instructions. Right now I am enjoying a sense of euphoria that comes with successfully completing a project that was at times challenging and ultimately rewarding!
As for now, I have a speaker to break in and a new project to start. Next on the bench is the BYOC Tweed Royal kit which looks to be like a really great package!
I ordered the kit and waited the 3-4 weeks as the Weber site indicates. I chose a custom green covering with a green pilot lamp and wheat grill cloth. Being able to completely customize your cabinet at little (if you go crazy with the options) to no extra (if you choose standard options) is a nice feature.
I also chose to get the Weber 15" alnico speaker with it.
When the kit arrived, I was surprised at how light it was. I am not going to say it isn't heavy, but it isn't as heavy as a similarly sized amp.
The cabinet looks good. Some of the tolex work could be marginally better and the cabinet's joints could certainly be tighter, but honestly, I am nitpicking here. The cabinet looks sharp and I have no doubt that it is structurally sound and infinitely nicer than virtually anything on the market from any of the mass produced companies. It is a solid pine box.
The speaker came premounted in the cab. I didn't check the nuts that hold it to the baffle. If any sort of rattling develops later, that'll be the first place I look.
I like the a la carte options with the kits. I don't know what type of tubes Weber supplies with the kit, but I opted not to have tubes or a copper cap rectifier supplied. I have plenty of 5U4's and other common tubes around. That saved me a few bucks which covered the additional shipping charges which were more than fair.
The kit portion of the amplifier comes with no instructions other than a schematic and a wiring diagram you can download from the Weber website. I printed both of these on my black and white printer as well as the transformer wiring diagram.
The power transformer comes with way more taps than you need. In particular, it has a lower voltage secondary in case you opt to use a solid state rectifier instead of a a tube rectifier. I thought this was a neat option but ultimately decided on a tube rectifier. Could I picture a Fender clone any other way? Absolutely not!
Being that the kit had no instructions, I just kind of soldered the parts into the eyelet board and left very generous lengths of wire where appropriate. This isn't the most resourceful way to assemble an amp if you are short on wire, but it allows for a lot of screwing up.
Shortly upon getting started, I noticed that I was missing a preamp tube socket. I contacted Weber and without question, the sent me a socket. I truly appreciate that! It is why I will continue to shop Weber. Customer support goes a long way with me!
While mounting the transformers to the amp, I noticed that one of the transformers is meant to be mounted at a 45 degree angle. I wasn't crazy about this arrangement because the mounting hardware interferes with the board laying flush against the chassis. I drilled new holes and mounted the choke more in line with what Fender would have done. To be honest, I am not even sure whether the choke or OT was supposed to be mounted at the angle. Both ended up mounted like Fender did on their Tweed amps. In order of how they were mounted, I went PT, OT, Choke. It made the most sense with the wiring.
I actually bothered to look at tweed chassis photos just to see what Fender did. It is worth noting that I put the nut end of the bolt inside of the chassis and had I put the head of the bolt into the chassis and the nut on the outside, I could have stuck with Weber's 45 degree angle transformer with no issues.
While I was modifying the chassis, I moved one of their wire through holes to another part of the chassis that was more in line with how the wiring diagram looked. I used a cold chisel to debur the hole which worked really well. I should have moved both of the wiring through holes, but I'll have to remember to do that next time.
The other through hole sits right under the board and lifts it which doesn't hurt the board any, but would have made things easier when mounting the board or moving wires from the OT and choke to their proper connections had I just moved the hole and inch or so.
I also would move the transformers further away from the PT so that I could stick an adjustable bias pot in. The amp is a non adjustable fixed bias. I don't really have a problem with that, but having the option to adjust the bias would have been cool if I wanted to stick a 5Y3 and a couple of 6V6's in. I'm sure I'll be able to figure some other way out when it comes up.
Weber supplied wire with the kit. It is a cloth covered type that is not a pushback wire. It is just a cloth sleeve over a normally insulated wire. It was easy to strip though (which some cloth insulation is not) so I cannot complain. The wire was all 22 gauge. Some of it was stranded and some of it was solid.
I do no like using solid wire as much as stranded. It isn't as durable, which may be a non point in the case of the inside of an amplifier where the wire isn't being moved so much. But it also doesn't have the same current handling abilities. I used all of their stranded wire and stuck the solid wire in my "box o' wire" where all of the spare bits go.
I've noticed a lot of amp kits and even professional amplifiers give very little discussion to the filament wiring aspect of amplifiers. If you look inside of a blackface Fender amplifier, it looks like the heater wire was literally the last step...almost like it was an afterthought. Morgan Jones has a wonderful book Valve Amplifiers which is really worth obtaining and reading if you are into building and designing amplifiers. It gets technical rather quickly, but also goes into a lot of theory which other authors don't mention at all or give a very brief explanation of.
He suggests running the heater wiring first because if it is done right, it will never need to be run again and only stands to get in the way should other work need to be done. Twisted wire should be used and pushed into the corners of the chassis for optimum hum cancellation. I tried using some of the cloth covered wire for the heaters but it just knotted when I attempted to twist it. I am lazy, so I took two equal lengths of wire and locked one set of ends into my bench vise and the other end chucked into my cordless drill. Then I slowly pulled the trigger while holding the wire taught. With the cloth wire it was just a mess of knots. I used some loose 18 gauge wire I had around and it twisted perfectly. Unfortunately, the 18 gauge wire was simply too large to get into the 9 pin miniature sockets so I went with 22 gauge wire for the preamp sockets and 18 gauge wire for the power amp sockets. If I had 20 gauge wire, I'd have used that for the preamp section. Again, it'll be on my to do next time list. Maybe I am just going overkill anyway. I've been accused of it before.
I also used some 600 volt 22 gauge stranded wire I had when I ran out of the wire the kit came with. Again, I probably had enough wire had I used the solid core wire. The 600 volt wire differs from the 300 volt wire in that the insulation is much thicker. This will keep any arcing through the insulation at bay.
One thing that I thought was really screwy was that the resistors were all metal film resistors with 5 band color codes. I literally double checked every resistor with a meter since I am used to the normal 4 band color code.
Some of the resistors were also different wattages. I really wanted to use all 1 watt plate resistors, but a lack of preplanning prevented me from doing that. It wouldn't have been any more difficult. Some of the resistor leads were unable to traverse the distance between the eyelets and have to be soldered onto the leads of other parts. I am not a fan of this practice, but impatience got the better of me. I could have ordered parts with the correct leads or wattages I wanted but I just sort of used what I was given. I am sure the 1/2 watt resistors will hold up just fine. Given the great number of Fender amplifiers from the 50's with the original resistors, I'd say I have nothing to worry about...but I just like to overbuild everything!
The caps that came with the kit were Weber's caps. I have used them in the past. They are very inexpensive and work well. I have no complaints.
The pots are kind of cheap. I don't know that anybody makes a modern pot that is all that good though. Most of them have tapers which are not as good as old pots. It is apparently cheaper to make pots with two linear taper tracks that approximate an audio taper than it is to make a pot with a true audio taper. This leads to all kinds of weird performance.
I also didn't like that Weber doesn't supply a second nut for mounting the pots. I wanted the pots as low as they would fit onto the chassis so that the knobs didn't have an unsightly gap between them and the faceplate of the amp. I had some loose nuts in my random junk parts so I was able to make that work.
You have to be careful when you tighten the pots and other parts onto the chassis faceplate. The chassis has a very nice and heavy chrome with white letters that are silk screened on. The lettering can be a bit fragile when you challenge it to a duel with a wrench. I saw a post online about somebody using some sort of tape to protect the lettering which in turn pulled the lettering up. Just be careful when you assemble it and you won't screw up your lettering. Or maybe you don't care and think it just gives it character?
The knobs that Weber provide are kind of junky. One of them had a set screw that was missing the head. I used a bunch of salvaged old stock knobs instead. If the last knob had a working set screw, I would have used the ones provided.
You are also given two wood screws (or are they self tapping sheet metal screws?) to mount the board to the chassis. The holes they are to go into are much too small. I had to enlarge them. I also had to run various other screws through the holes to get them even started. One of the screws sheared off at the head which required me to use some linesman pliers to remove. A bolt and a nylon standoff would have been much easier and just as secure. Again, impatience got the better of me. Next time I'll go to home depot to get the standoff and bolts. Instead I just forced a bunch of metal screws through until I found ones that fit the way I liked.
The amp goes together really easily if you can read a wiring diagram. The only thing I had major troubles with was the grounding scheme. There are lots of ground points referenced throughout the amp and most of them go to either the heavily chromed chassis or the brass grounding plate.
Neither are easy to solder to. I have a heavy duty 60 watt iron (in addition to the more surgical regulated iron I use regularly) and it barely was able to get anything to stick to the brass plate. I didn't even try to make it stick to the chrome.
My understanding is that the chrome finish is toxic if you bring it to high temperatures or if you removed it (and subsequently breathe it in) to solder to the steel beneath it.
The Weber chasiss did have one interested feature. There is a copper stud welded to the chassis near the PT. I soldered a terminal strip to the copper stud. Then I connected all of the grounds to this copper stud/terminal strip setup.
For the cathode of the power tubes, I ran them to this terminal strip with a 2 watt 1 ohm resistor so that I can measure the combined cathode current should I ever get around to putting an adjustable bias setup in place. Since I run matched tubes, there shouldn't be any problems with one tube drawing more current than the other and giving false readings.
For the pots and jacks, I gave them a ground bus which was just a solid piece of wire run along the backside of the pots. I then grounded the 5 connections from the board to this bus. One end of the bus was connected to the grounding terminal strip. I am sure I should have isolated the input jacks to prevent ground loops, but I have seen Gibson amplifiers with this exact setup and no concerning noise issues.
All of the wiring kind of came together really fast after the board was wired up and the sockets had the heater wires run. I was actually unprepared for the moment when it was all done.
I had the power and preamp tubes but no rectifier tube. I loaded the JJ tubes in and rummaged through my many boxes of old tubes and found a loose GE 5U4. I was in business!
I plugged in the amp and kicked the power switch on for the first time. The pilot light was bright and there were no blown fuses. Surely, this was a good sign!
I grabbed the Kramer Baretta I have been working on for a friend and plugged it in as it was the closest guitar. I'm actually more of a Tele/Strat/Jazzmaster player. I used a cord I had made out of some Belkin cable wire which is really low in capacitance and resistance. At 10 cents a foot, the switchcraft ends are the most expensive part of it.
I flipped the standby switch and heard what can only be described as the rush of life into the amplifier for the first time. I'm sure Dr Frankenstein felt the same way!
All of the knobs (except the volumes) were set to 5. I did a check of all of the controls and inputs doing what they were supposed to.
One thing that really surprised me was how absolutely loud this amp is! I felt it deafening me even at 2 (out of 12)! This goes back to the pot tapers I mentioned earlier. There is some hiss from the amplifier that could be caused by lead dress (I didn't use any shielded wire) or maybe it is just inherent in the circuit or tubes. The noise definitely went away as the treble pot was adjusted.
It isn't a loud hiss by any means and I have no desire to track it down. I have owned much lower wattage amps that made much louder idling noises.
The presence control is interesting on the amp. I expected it to make the amp brighter as I turned it up. This is what typically happens anyway. What actually happens on this amp is it just gets more raw as the presence control has a large .1uf cap on it which allows almost all of the frequencies to bypass the negative feedback loop. I played with that control the most. It is subtle and I'm sure it'll do more as the amplifier is turned up, but at low volumes, it is noticeable and I think I actually like the control set more toward 1 than 12. After I get to know the amplifier a little better, I may change my tune and come up with favorite settings.
Overall, I was really impressed with the Weber kit. It is by far the cheapest kit in the internet and probably the most versatile in terms of what you choose to get with your kit. Some of the things I didn't like just come down to personal preference. I know it seems like I had a lot of trouble assembling the kit or had problems with most of the parts, but it actually went together very smoothly and I spent more time thinking about what I was going to do than doing it. I also like the ceramic sockets that they supply. The OT has 2, 4, and 8 ohm taps which is also nice. I'm not going to say that this kit is for everybody. If you don't know how an amplifier should go together or this is your first kit, you are in for a hard time. There are no printed step by step instructions. Right now I am enjoying a sense of euphoria that comes with successfully completing a project that was at times challenging and ultimately rewarding!
As for now, I have a speaker to break in and a new project to start. Next on the bench is the BYOC Tweed Royal kit which looks to be like a really great package!
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