Do It Yourself

I had a problem with the last amp i built with pcb mounted sockets where the tubes werent straight (probably because the sockets werent parallel to the board. anyone have any tips on how i can get the sockets all mounted level so the tubes can stick out straight?

Anyone here gander a guess (or someone that's built one) how difficult it is to build (battery version)? I wrote off getting one since I didn't want to wait for the Digikey order and the order from Hagerman but someone is selling complete kits on ebay so I'm thinking I might as well do it. And it might just outperform the NAD PP-2 for less.

I'm finally going to break down and start doing my own soldering, and thought that maybe I'd make some adapters so that I can use other sorts of tubes in my Singlepower (tube complement == 3 x 6sn7's). 7n7's should be easy --they're just a rewire. It was suggested that I try 5687's. Based on this: and other posts (mostly from Jacob), it seems that it's not a straight rewire. Anyone have any idea what the "schematic" would be? Any others that are straight rewires that I should also try? Thanks for any info.

Any of you ever across this stuff? Discrete opamps and 78xx/79xx Vregs? https://sparkoslabs.com/ Wonder if the regs are any good and how they compare to Amb's o78/o79?

I started to think about upgrading my HT and my new plan is to have an AV processor plus power amp. After searching for a while, I figured that Hypex might be a good choice as a power amp. What would be a good option here? A) 5 X UcD400HG with HxR Softstart module Exodus MCH Power Supply Transformer 115/230V x40V 1KVA 5 X UcD400HG with HxR SMPS1200 Plus of course heatsinks, case and other accessories. My current speakers (Infinity Cascade Model Nine, Three C & Three V) don't need that much power, but you never know when upgradetis hits you and UcD180HG with HxR costs only a bit less. So, what do you think? Should I look for something else or …

Toying with the idea for my Dynamite. Anyone hear the Goldpoint smd design vs the Dact? How about feel? Just put in a 4-ch Alps blue velvet pot, to replace a cheapo I had. I also put in pre-attenuation resistors cause I had the old pot turned to almost off for the levels to be right. Much better.

Trying to make some DIY USB cable, but I cannot seem to find USB 2.0 type B male plugs anywhere in USA, only some from China on eBay with long shipping estimates. Found some type A plugs on Amazon. For type B, looking for something like these: http://www.ebay.com/itm/170578212079?_trksid=p2060778.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT

http://cgi.ebay.com/OLD-Fluke-407DR-Plate-Filament-Rack-Tube-Power-Supply_W0QQitemZ160184703511QQihZ006QQcategoryZ58287QQssPageNameZWDVWQQrdZ1QQcmdZViewItem If you have room for this thing...

Any preferrences on these? Biggie.

For the Carbon I am building, the user would like to be able to bypass the volume pot, but would like it switchable for when the source doesn't have a volume control. I had initially told him no problem, this will be easy. The more I thought about it, I realized it isn't quite as easy as I had surmised. Simply shorting the input to the output (wiper) would still result in potentially bad things depending upon where the pot was in its rotation. Since I had already done the pot adapter boards for the gb awhile ago, I started with one of those for pcb layout (the pot I am going to use is a TKD CP2500 4 channel). My initial thought was to take the pot completely out…

with that video of a home made tube going round these days... (and it turns out that guy was someone i worked with back in the midwest hifi days 30 years ago) I figured i would show a picture of a tube i made by hand in 1976 (at zenith) Has a couple of bugs in it. (actually a bug and a butterfly) http://gilmore.chem.northwestern.edu/tube1.jpg http://gilmore.chem.northwestern.edu/tube2.jpg Proving without a doubt that i was nuttier, longer than just about anyone. (made from picture tube necks)

Anyone have a LM337T they could pop into an envelope and send to me? Hate to place and order for a $.50 part with $10 shipping.

So I hate 99.9% of headsets on the market because the headphone portion is always uncomfortable as all hell, and the ones that aren't uncomfortable are huge HD650 style. So I have an uncomfortable ass folding headset thing from Plantronics and a pair of PortaPros I plan on combining. I've done some work so far but this seems like it will be almost too simple of a mod. The PortaPros have that random screw hole that does nothing on the left side and the Plantronics mic is on the left side of that headset with a pivot point. So far I demolished the Plantronics headset and got the mic out of it unscathed. I took the tiny screw out of the side of the PortaPros …

Uh yeah, so I'm failing pretty hard at figuring out why the right channel doesn't make sound. I checked the DCR from each tab of the dynamic driver (which is hooked up to the electret, yes I did mod them so it's not run through the electret into the dynamic driver anymore) and it measures correctly, around 330 ohms. Measured from driver tab to tip/ring and it measures the same. The hell am I doing wrong here? I resoldered the tabs just to make sure, still to no avail, and it's always the right channel, and not the left.

http://www.ebay.com/itm/322416989057?_trksid=p2055119.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT Looks real in the pic and has a pic of a lockyz output from the curve tracer. Gets good feedback and all. Still no real way for me to tell from the pics. I was hoping to buy a set and ask one of you more experienced users to test them for me to see if they meet original specs.

i have the next 3 weeks to kill before school starts again. id like to do something productive with my time. i dont know anything about electronics (well i know a little but assuming that i dont know even that will probably be safer for me). i would like to start working on either an amp or a dac that is fairly easy to build. cost is a slight issue so the whole thing should be less than $100 including tools. i already have a soldering iron but no solder. also, i dont know how to read a schematic, much less know how to plan out the layout of the build, so step by step instructions would be highly appreciated. pictures would go a long way too. lastly, id like to build s…

Hey guys, I finally found a good home in a small space for the Moth Cicadas I purchased many moons ago, and the room is conducive enough that I can really notice a bit of variance in the drivers. I have a set of unused spare drivers I'd like to sub in, to see if they are more to my liking. The only trouble is, I have no clue how to remove the old drivers. The cicada enclosure is ported, but the port is too small to fit a hand in, so I can't push the driver out from the back. It fits in the cabinet pretty snugly, so I don't have enough room to fit a spudger in around the edge and pry it up. Furthermore, being paper cones, I run the risk of damaging the old driver is I …

Looks like a DIY ESL? Best regards Moray James.

the output on my Zhaolu is too high. I have had some issues with it in the past, but never that bad. However with my two most recent purchases, a Marantz Sr7001 receiver and a MPX3 SLAM I am running into problems. The Marantz's Peak light shows and the sound gets distorted at times because it can't handle the inputs and I can't turn the volume up past 7 o'clock on my mpx3. I've considered getting some of those RCA adapters to reduce gain by 3db or 6db, but I realize that is not an ideal fix. So does anyone have any experience with the Zhaolu 1.3? Can I change the gain on it?

I'm looking to give my headphone cables a more professional look like this http://redsecta.files.wordpress.com/2012/03/650cable.jpg I want to find splitters like this guy used

Finally found a way to get cheap output transformers for my amp after reading this page. All resistors are 1/2W unless otherwise noted, coupling caps should be 250V or better. The power supply capacitors are all 240VAC motor run caps from Aerovox which I scrounged for $5 a pop from the surplus store, and the chokes are also cheap surplus store goodies. You don't have to go nuts on the PSU like I did, I just felt like building an amp with no electrolytic capacitors anywhere in it. The output transformer is actually a 50W toroidal power transformer from Amveco (~$20 each from Digikey). If you have high impedance 'phones or simply listen loud then connect the seco…

I have a pair of 2n5457/5458 JFETs on a small board as part of a bias scheme for a 12AX7. The circuit also has a 9v battery. I cannot get the voltage dialed down, so I checked the JFETs. The resistance from gate to source (and gate to drain) read the same in both directions: roughly 1k ohm. These are dead, aren't they?

I have two OBH-11SE's. One of them is broken -- it's mono; other than that, it sounds fine. I got it used. I suspect the previous owner was messing with it. There appears to be an additional jumper from Q9 to Q11 (similar to the one from Q5 to Q6) -- could this be the cause? Or is it a red herring, some sort of tuning thing? I don't see a stray dollop of solder anywhere, but I could be blind. Does anyone have any ideas? Does anyone have a schematic of the thing? Tell me what to measure and where, and I will.

Hi everyone one year ago I bought two Aikido 24V and two Max Millet boards, I have assembled them with BJT and MOSFET. Great DIY project, great sound, really. The "valve sound" when I was young.... I like very much the Aikido sound with the LM317 buffer (great idea!!!!), this is my preferred headphone amply, and I like too the Millet diamond buffer stage, so why don't create a new headphone amp with the best of both Aikido and Millet? Et voil

OK, so I need to replace a resistor on one of my ESL-63s so it matches up with the one Kent repaired. Kent sent me very detailed instructions that I think I'll be able to follow. Basically I have to unsolder a wire, unsolder a resistor, install the new resistor and resolder the wire. The rest is just disassembly that can be done with a screwdriver. My screwdriver skillset is pretty strong so I think I'm OK there. I'm looking for suggestions for a soldering iron. Currently the resistor swap is the only task on my DIY schedule. To be honest I doubt I'll be constructing CMoys anytime soon, but who knows? So I don't need the best iron ever but I want to avoid buying ju…