Sean, where is John Risches site? I am getting ready to move and want to get some ideas for sound absorption to tweak the new room. |
An Audiogon member and best friend Jcbtubes built my pre-amp from scratch and does incredible mods on tube amps and pre-amps. He is an EE who should quit his job and go into the audio business. All tube gear that I own has his magic touch. His modified Cary 805s make the original amps sound vailed and tired. His homemade pre-amp has gone up against the finest out there and bettered each one. If I have a problem with my gear or am looking for improvments in my system I call the man. Every audiophile should have a Jcbtubes. |
I've built amps designed by Nelson pass. Very simple circuits and requires very few parts. Sounds pretty good too! |
Sean: I am in a weak kind of way. My current interest is retro-fitting male IEC plugs to my HTS2000 power conditioners and as of today (due to an informative email from another member) also upgrading the power outlets in the unit (the ones that I use anyway) as well. I have no idea which wires go where, so will use a $6 outlet tester from RS to find out the proper hookup by trial and error. As noted in another thread, I had an inexpensive but well endowed (with upturned spikes for each shelf) bolt together equipment rack mig welded into a one piece unit by my auto mechanic. He did not charge me for the work and this project was just to save $300 or so on a one piece rack. I would prefer (for the time being anyway) to hire out the work on these projects (like the Monster conditioners right now), but do not know of anyone local that does this type of work for a reasonable hourly rate (I mean that this is pretty basic stuff not worth $65/hour in my way of thinking). A friend of mine brought over a pair of the DIY micro wire IC's (in copper) to try out on my system and I will give the silver version of this IC a shot after I clear out some of the other household projects that I still need to complete (new herb garden, relocating the Hi-fi system and installing ceiling fans in the bedrooms for starters). DIY bass traps are something else that I would like to try (now that my system has some bass:-) and I am looking into it. |
I got the DIY bug after soldering up a pair of Homegrown IC's without blowing up the equipment or burning down the house. Recently, in talking to Rodger Modjeski about tubes for my RM-10 amp, we got on the subject of passive pre-amps. He opined that very few active pre's have low enough noise to suit him and has used passive with cd for years. The result was that he sold me a kind of NOS Noble volume pot originally used in the ARC SP-6, some wires and RCA's and a recipe for assembling it all. I wired it up to a cheap Radio Shack metal box and wow! Big improvement in sound over the SFL-1 I was using and I built it. Well, I drilled the holes and soldered it. Wish you all could have been here when I plugged everything in and it worked. Postmasters are on the way and soon, I too will be able to say I cut into a speaker cable. I'm also about halfway through "There Are No Electrons" by Kenn Amdahl and when I can figure out how to get the green guys to the party through tubes, I'll design an amplifier myself. |
Jon Risch's website is listed below. It has quite a bit of DIY and technical info on it. Jon is an EE ( electrical engineer ) and has been involved in various phases of audio and sound reproduction for MANY years. He is one HELLUVA good guy and does his best to help people out while sharing his knowledge and experience. Hope you can find some useful stuff on his site. Sean
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http://members.nbci.com/Jon_Risch/index.htm |
Rmgcy, I assume you built the zen or son of zen pass amp. Where did you get the monster power 8 ohm resistors and the high current power transformer? I am considering builting the son of zen and I even have the heatsinks, power supply electrolytics (200,000 microfarads worth) and mosfets. But, oh boy, finding the power resistors and transformer for a 25 watt version is murder. |
Liguy: Yes, one of the amps that I built is the "Zen" with the improved power supply. I must waited over a year for the 2 output transistors to arrive after ordering them. Other than the transformer and the MOSFET, I got all the other parts at very little cost from the swap meet - a monthly parking lot event. It's unbelieveable how hot this amp can get and so the heat sinks has been quadrupled ever since so that the originally installed fan would not come on so quickly. I think I'll hold off building the "Son of Zen" until this California energy crisis is over!! |
I recently built an amp using Amplimo modules. Two years ago, I built a Marchand cross-over kit. In my youth I built dynacos and heath kits. I have also built several speaker systems that all exceeded my expectations, that I continue to use. Currently, I am ressurecting a "Daniel" pre-amp that had been reduced to a bag of parts. I would like to build a "pre pre-amp" for a moving coil cartridge but have yet to find a suitable circuit. It is great fun! |
Sean, I noticed in another post that you are an EE. I am also but the twist in my case was the degree was an attempt to understand the reproduction of music. To that end EVERY part of my system has the DIY touch. BTW I had a Pass A40 for a few hours untill it over heated!!! |
Rjf, a long time ago I built a Marshal Leach pre-pre amp. It was battery powered and was quite good. Dr. Leach has a web site and I think the schematic is still on it. I also had a Daniel. I can clearly remember how good Cat sounded with that rig even though it was so long ago.
Chris |
Great thread! I have been DIYing everything I have owned for years! As an Electrical Engineer, I have discovered that virtually every component or speaker can be improved regardless of price. For example; Dunlay speakers : change out the Inductors, Capacitors and Resistors with quality parts (from Northcreek for instance). And by all means use impedance compensating networks across the drivers! With these improvements, these speakers are DRAMATICALY improved. Why more high end speakers don't use zobel network across each driver is a mystery to me. This is a no brainer mod for any speaker that does not have them , and most do not. Amplifiers: use black gate capacitors in the power supply, parallel high quality film caps across each and every fuse (except power supplies), and for the more advanced, rebuild the front end and output stages (non tube designs) with better transisitors which have high slew rates, fast settling times and symetrical distortion characteristics. Also, make sure that all transistors use active FET current sourcing (as compared to the resistor passive sourcing on the transistor leg). For example; Aragon amplifiers will dramaticaly improve with this mod. The cost? $12.00! Cables: build your own, save a fortune, and learn to detest those stupidly expensive "recomended" brands. My favorite? Stan Warrens T1 design (He can also build these for you at a very resonable price, if you don't want the hassle). These cables are way, way up there sonically, and have NO identifying signature, as compared to many other super expensive brands. Cd players and DACs; Strip out the output devices and replace them with a real output stage. Again if this is too much for you, Stan Warren is a great source, for this kind of mod (along with digital filter and power supply enhancements). In the end, DIYing will give you sound improvements that YOU CANNOT BUY, FOR ANY PRICE! I and others have examined quite a bit of the high end stuff out there, and unfortunately, it seems as if every "audiophile" manufacturer somehow misses the boat, with his design execution. Ironicaly, the above modifications that I have breifly described are NOT advanced thinking!. They are basic improvements that any competant engineer should utilize. Yet so many of the big name companies don't! (I wish this wasn't the case , I am fortunate enough to afford some of the more exotic stuff, and really don't have the time to do the above mods. Sometimes it takes me over a year to finally finish some of the more advanced DIY projects). For the rest of you who just want to save money, the above DIY recomendations will make you think twice about spending stupid money on high end gear. I'm sorry to say that most of the so called "high end" companies, are NOT the gestalt, that everyone seems to think they are. Have fun DIYing, learn to love music (not equipment), and save that money for your kids college education. If you don't have kids, spend your savings on more pizza, cars, beer and women! (Not necessarily in that order...Ha!) |
Just to correct an error or misconception here, i am not an EE and have never been to any formal "school" for electronics. I am pretty much "self taught" via personal study while receiving "insights" from friends that are EE's or folks with their bachelors. Combine this with a LOT of hands on experience and that's where i fall into the game. As such, i am always willing to learn but am also limited in my current understanding and level of electronics knowledge. As was mentioned in previous threads though, this hasn't stopped me from working on electronics for a living or as a design consultant for over a half dozen manufacturers in my field of work.
In some ways, not being "trained" to look at things from a "conventional" textbook point of view has helped me. In other ways, my lack of formal training also puts me at a disadvantage compared to others that may have a better fundamental knowledge of what is going on in a complex circuit. Between my business partners degree and studies in electronics and my hands on experience, we have been able to work together quite advantageously though.
If i offended some EE's in one of my other posts, i do applogize. I have a great amount of respect for those that have formal educations in ANY field. It takes a LOT of patience and hard work to achieve what they have done. However, i do have to say that i have even more respect for those that make use of that knowledge and are NOT content to sit on their laurels. Push the envelope of your knowledge and skills, for your own sake. Sean
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Ehider, i think that we were posting at the same time. Thanks for sharing your insights with us. I've found pretty much the same things that you stated to be very true.
As to your comments about Zobel / impedance compensation networks, they DO have a downside though. It is called "power consumption". While the design may actually measure and sound better when "zobel'd", it will also suck more juice from the amp. If you have a limited power capacity to begin with, such as with a low powered tube or "set" amp, zobel's are NOT a good thing. As such, the engineers, designers / builders have to work with the intended market. Once this comes into consideration, you have to start thinking about MSRP, profit margins, etc... While some VERY beneficial mods can be done for pennies on the dollar, those pennies can add up VERY fast when your talking about large production runs. As such, that is one of the reasons why / how i got into this hobby. Just like you said, you can make GREAT improvements to various commercial designs with little cost or effort other than your own personal "elbow grease" and a FEW bucks here and there. Sean
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I don't know if I could be referred to as a DIYer, but I have done a bit of tube rolling and speaker modifying/designing/building in my time. Don't have the woodworking skills to build a "furniture quality" pair of speakers, but cabinet makers are always willing to help. I have not done much in the way of getting my hands dirty in the past few years, basically because of lack of time and the fact that I am satisfied with the sound I am getting from my system. I used to be of the opinion of Ehider, where things like Zobel networks, notch filters, and more components was the way to good sound. It was all impressive, and educational. Then, I started to swing back the other way. Feeling that less was more. I guess part of it was the migration to tube amplification(and its magic). Not having the current to blast through complex crossover networks, they work better with simple crossovers. And the simpler, the better. Often, the midrange driver running flat out, the tweeter only needing a capacitor and perhaps a resistor. The woofer an inductor, or maybe nothing. Parts quality being critical. As Ehider says, NorthCreek can teach us a lot regarding the effects of improving crossover parts quality. I have also come to the conclusion that wiring and solder makes a difference. To the point where I have gotten best sound from no solder at all. Rather I use a "real" crimper(NOTHING like most of us have ever seen - makes a true "cold weld") I got from Boeing Vertol's helicopter division to butt splice connections together wherever possible. Love the fact that some of us refuse to overpay for BS when we can do much, much better ourselves. |
To start out, this is a great thread. The following is only my opinion on some of the above ideas. I really want to continue to exchange these ideas and discuss any and all implications. If this leads to some heated discussions, then I say GREAT. I have found that the best understanding of a topic comes from defending one's position. I hope this thread can enlighten us all to the wonderful world of DIY audio. And now my ideas.
Ehider, I can really relate to your enthusiam. I can remember when I 'discovered' the differences of crossover components. I also agree with Trelja about the simplicity of a crossover for his (tube) application. (and yes you are a DIY'er) Neither approach is fundimentally more correct than the other. My experience indicates that to get good results with a simple crossover that the drivers and cabinet must be selected VERY carefully. This may not be possiable when you are trying to modify a speaker you already own. In the latter case a zobel may be the ticket at the expense of power consumption.
On the topic of circuits, it is not always safe to just replace transistors in an amplifier with what is percieved as better units due to the possibility that you may change the stability of the amp. If the transistors are wider bandwidth, you might make your amp into a high powered oscillator and smoke your speakers. If one has access to an oscilloscope, the stability of the modified amp can be easilly checked. The bias current of the output stage will also need to be adjusted in some cases. I agree that the difference can be audible, but we must be careful! I recall where a friend of mine was told to increase the size of his power supply caps. He did, by a factor of 10, including some caps that were not in the power supply, and now the unit is dead. A lot of this DIY stuff is very easy to implement but common sense must be applied.
It is also a super cheap tweek to replace the resistor in the differential input pair with a current source. I have done it a dozen times and every time I am blown away with the improvement. Siliconix may still make a current source 'diode' that looked just like a reistor. It was simple to replace the resistor with the FET current source as long as you knew the correct value of current source to buy. I will research the availability if anyone is interested. The Aragon 8008BB already has current source transistors in the input stage but I don't know about the other models. Please let us know about the input configuration of any models you are familar with. BTW there are several easy mods for the 8008BB.
I have not heard of putting caps across the fuses. I must admit this is so simple that I feel stupid for not thinking of it. If the unit has DC power supply fuses (like the 8008BB) the caps would help to deliver transient currents to the board and ultimately to the speakers. The only place I would not put a cap is across the AC line fuse. On second thought, that might help get transient current INTO the power supply! Let's hear (see) everyones ideas on this. The cap would need to be small enough that it would not power the unit if the fuse blew, but large enough to help get transient current around the fuse. Are there any implications we need to watch out for?
Trelja, there are many people that believe the cold weld is the way to go. WBT makes an RCA that does not use solder. My many years in the aircraft industry has me very familar with the crimpers you mention. They are very pricey!
THIS IS A SUPER THREAD! Maybe we can get some of the non believers to try some of the DIY cables or some simple cap modifications and listen for the difference. Under the controlled conditions of their own system they may begin to understand what Walt Jung told me "Everything makes a difference".
I enjoy looking at schematics, quite often I get an idea or learn of a new part from looking at them. If you can get me a schematic I will be willing to try and assist anyone with a mod of their electronics. My business does take me out of town all the time but I will respond to email as fast as I can.
Chris Owen
Comm-Tronix@KScable.com (work) |
I would like to thank Chris (Sqjudge) for the lead on a circuit. Thank-you! |
thank you for posting this thread. I DIY all of the time, from speakers, preamps and amps. I just rebuilt and up-graded the base to my REGA table. I also up-graded the shelves in my equipment rack by gluing a sheet of dense fiber board to the bottom side, then using a .020-.030 sheet of sorothene type material in between another sheet of fiber board. It added a lot of mass to the selves and had a positive effect using them under my tube amps. Hi-Fi and music is my hobby and one of the few hobbies I know of that can cover so many areas of interest. |
I have become a first time DIY'er without intending to do so. I bought a pair of Apogee Stages because the price was right and I have always been intriuged by what people said about them. LOVED the sound immediately but thougth it had some shortcomings as well. The good folks at the Apogee web site suggested crossover component upgrade and the descriptions of the improvements were compelling. I went the Northcreek route and replaced the stock ASC caps with Northcreek caps in a bypass arrangement. I am happy to report that the across the board improvments were WAY beyond what I had expected . . .wider, deeper, blacker background, smoother yet dynamic and detailed. It was a shocker to me. I expected a tweak and got a major component upgrade. Well, naturally I am taking it to the next (and pricier level). I have ordered 8ga inductors with some of the lowest DCR values around and plan to construct an external crossover board to house these larger and better components. If it gets much better than it is now, I will need to purchase incontinence pads. |
Comchenry: Keep it up. The pads are a drop in the bucket. |
Okay, so let's say I have a soldering iron, no training and some enthusiasm, what would you guys say is a good sort of tweak to start with for a digital source/integrated amp/2 way speaker system? Whatever has an appreciable return but doesn't have much risk for irreparable damage. Bonus points if the parts are available from the local rat shack (I hate waiting for packages) but I'd rather do it right. I was thinking of trying some DIY ICs since I work at a cable station and have access to plenty of coax, they just don't seem to have any of the particular Belden types I've seen mentioned for this.
I'm all for non-electronic tweaks to, and I have much more experience building things, but it's just not the same as messing with the signal path. |
Grungle: Buried somewhere at Audioasylum are posts on a DIY noise reduction device that plugs into any electical outlet (kind of the same principal as the Blue Circle thing I think). Boy, I hope that Kublakhann does not read this post and get any ideas of making one. |
Grungle: try a making a fancy PC out of good quality rat-shack cord. Get a strip of SSTP or similar wire (with multiple foil and mesh shielding). Given the wire diametre, get +1,0" diam outer tubing (ptfe, if you can find it. If not, whatever "good quality" is available), and 1/2 the length strip of of heat shrink that can fit snugly over the tubing. Strip the plastic dielectric from the wire. Expose the conductors, @~1" folding back the insulation matls (foil, mesh). Thread the wire into the outer tube. Seal on one end with a strip of shrink-wrap so the actual wire is in the middle of the tube.
Now to the tricky part:
Fill the inside of the tube and around the wire with tiny lead shot. Fill tightly, but keep in mind that the end result could do with flexibility (unless that's not an issue for you). Seal the other end with shrink wrap. Double seal both ends with tape or use extra shrink-wrap. If you find outer dielectric mesh (expensive!), use that over the tubing. Now connect conductors to IEC & 3pin. IMPORTANT: ENSURE CONNECTIONS ARE CORRECT ON EITHER SIDE (phase-to-phase, ditto neutral & ground)!
Voila, you've got a mechanically isolated and impressively thick-looking PC. You could be susprised with the sound, too!
Cheers! |
Sean, at a certain point I could no longer endure certain capacitors or chips or transformers which seemed to clog a singer's lungs or take the flesh off of the world's best orchestras in my system. It was with the hope of vanquishing these petrifications that I started to imitate the solitude of a monk trying to integrate an old forgotten tube procured from the city where I currently live (Siemens F2a) into an amp circuit of original design (a failed project, BTW: Shindo does it better than I ever could) or build a Thel nuclear power generator for my system (an insane DIY project stemming from my dissatisfaction with the AC from the public electric works--I told my wife to actually shoot me if I ever got this kit, and I got it anyhow). Doing this I suddenly felt further distant from the well-lit and slick high-end showrooms than if they were on an undiscovered planet (advantage no. 1: DIY de-fetishizes the high-end commodity spectacle), and my eyes, turned now towards the DIY publications, started to envy the dynamism of autonomy and independence from the sometimes sick and self-defeating high-end audio market.
I have known many passionate, intelligent audiophiles that would not even open up a component in order to stare at a particular aspect of it that is infuriating (an undersized transformer, an embarrasingly cheap cap, etc.). They would consider it an absurd effort! Their nerves, warded off by the "Do not open! Danger of elecric shock! No user-serviceable parts inside!" labels (with or without skull and cross-bones depending on the voltage of your output tubes) has suspended their curiosity (not to mention audio magazines that do not publish photos of the circuit boards of components--mostly an American phenomenon). Nothing will waken in them the need to improve things, extinguished by warnings and warranty conditions, forever frightened off by those prohibitions or by the perceived loss of that prestige (and re-sale value) that many of them desire above all else. Proud owners of analytic, high-powered, dry and un-musical sytems, forever beyond the sounds of sizzling solder, beyond the world of DIY.
The true GREATNESS of DIYers (and, I would even include those with unknown components without prestige or hideously ugly components) consists in that incomparable power of defeating the fear of ridicule. I know some high-end snobs (that is exactly what they are) who cannot put a DIY cabe in their system without shame; DIYers invoke the "gift of DIY." An absolute preoccupation with elite brand-name manufacturers immobilizes those proud owners into becoming spectators of their own repressed freedom to manufacture their own systems, their imagination does not flow in the direction of this or that modification or adjustment. Yet THE AUDIOPHILE'S RATIONAL FUNCTION IS NOT TO LISTEN BUT TO BUILD; and REALLY TO LISTEN WE MUST PARTIALLY DEAFEN OURSELVES (to hum, to hiss, or other technical imperfections): that is the condition of ecstasy, of the one revealing audition, whereas DIY perception is exhausted in the horror of the "already heard," of an irreperable recognition scene which occurred at the beginning..
For the audiophile who has foreseen the futile exploits of the big-manufacturer audio world, and to whom this knowledge has afforded only the confirmation of an innate disenchantment, the scruples which keep him from picking up a soldering iron and a circuit schematic (and attending night courses in electrical engineering if needed, and accessing the DIY pages on the internet) accentuates his predestination to melancholy. And if he actually envies the DIYers exploits, it is not so much for their disgust with components as they are or their transcendent appetites (a saint lurks in the will of some famous DIYers, Risch among them), but rather for their victory over that fear of ridicule I mentioned before, which he cannot avoid and which keeps him on this side of the indecorum and sometimes downright ugliness of DIY components.
I know that was long, sorry, and I did not go into detail on my DIY projects (another time). DIYers easily forget about ridicule. |
Sean, my primary DIY project is being a single parent to my two young kids. However, when time permits, I'm working on an extensive room acoustics project (one of the advantages of being divorced is that I now control the remote and the room it's in). You know this because you've sent me plans for the diffuser - thanks.
To all the audiophiles out there, here's a thought. I'll bet 90% of you have maximized your hardware and are currently delivering 96% of your capability (limited by budget). But, I'll bet you that most of us are only delivering less than 50% of our room's potential.
Systems are only as good as our weakest link. Consider your room a link, and you have your next project! |
Excellent point, Dds! Sean, do your plans include a quick initiation course for the wife? |
Iv'e modified, or built, everything, in my system, with the exception, of the phonocable, cartridge, and tonearm. The biggest improvement, to my system, was when I built, tubetraps, ala Jon Rische. Which leads me to beleive, that room acoustics, are a big factor, in the sonic picture, we hear. |
