Yeah, I get RFI on ch.9 on my VCR tuner. Moving the DI/O about another foot away helped. |
I pulled the tube out when I first got the dac and out of curiousity, put it back in after a few days. I didn't notice any degradation of the sound putting the tube in, and it "seemed" a tiny bit better, nothing significant, so I have left it in for now. Could also have been my imagination, cycle of the moon, too much wine, etc. I want to try the A/D section soon, also so I will need the tube for that. The Stancor power supply made a noticeable difference, for the better. Ordered some 75 ohm video shorting plugs for it today to see if they help the RFI situation. FYI, if anyone is planning on ordering the Stancor from Allied, they have a $25 min order. |
I found that taking tube out of the ciruit inproved both stock out of the box mode and after intesive mods. It just sounded better with the tube removed. Most that I've heard from have found the same. |
steve, there seems to be a trade-off w/the toob in the circuit - you're correct that it draws power from the p/s, but it also reduces elec'l leakage (i'm sure this isn't the correct technical term!) from the adc side into the dac. best bet is to try for yourself.. some prefer it one way, some the other. if a di/o's only mod is the upgraded p/s, & internal parts haven't been replaced, i'd be inclined to leave the tube in. if lotsa mods have been done, yank the tube... doug s. |
JoeB: You're leaving the tube in for D/A? The tube is for A/D only, and will just draw from the power supply. This isn't a good thing.
Doug: BTW, Thank you. I bought the Apogee cable from fullcompass.com. I'm very happy with it's full freq. extention, it's ability to resolve low level information, and found it to be a very dynamic cable (both micro and macro). I'm sure that the FIM cable is better, one of my friends has their speaker cables and interconnects. However, at less than $30, the Apogee is a steal! It smoked the Monster cable that I'd paid around 3 times as much for. |
Thanks for all of your advice, Doug.
I think you're right about the tube. The sound became subtly more refined and relaxed with the tube in vs without so I am leaving it in for now. I just got the Stancor ps tonite and that makes a much more noticeable improvement.
I have ferrite RFI blockers on my Ic's but will get some more for the rest of the system.
I tried going w/o the line attenuators and it did not work out. Some aspects of the sound improved, like the size of the soundstage, but the sound got a bit ragged as I could hear my input stage starting to overload on dynanmic passages-not pleasant to hear. The Stancor power supply plus burn in time has improved the soundstaging.
I have tried the Radio Shack digital cable years ago and found it was very simiar to Canare Digiflex cable; not bad, certainly worth $10.
The Apogee is only a little better. I have owned both the old and newer version of the Apogee Wyde-eye. I am currently using Harmonic Tech Copper link, which I prefer to the Apogee. I have tried Monster data link and Ensemble Digiflux with the Art DI/O and I also have a Madrigal MDC on hand (which costs more than the DIO), but until the unit burns in, I think I will go with the Harmonic Tech for now. The Stancor ps has warmed everything up a bit, so I will try all of the above mentioned cables again in a few days and will see what I can do to get rid of the RFI. |
joe, you're correct that the tube warmth adjustment led's don't work w/o the tube. but, as the tube is in the adc circuit, these lights are meaningless when used as a dac only... folks have thought a possible reason why the unit may sound better w/the tube, is that it draws power away from the diodes in the adc circuit, & these, being crap, may let some unwanted signals feed back into the dac side. one of the recommended mods is replacing *all* the diodes, both dac & adc, w/schottky's, which work much better... could be part of the rfi problem you're experiencing. i'd suggest moving the dac, & the cd-player in relation to the tuna, to see if this has any effects. also, may want to put ferrite magnets on the power cords & interconnects. also, are you using any gain attenuation? the di/o, being a pro-audio product, outputs a 7v signal, while 2v is more typical of home-audio gear... i recall you mentioning using an attenuator module, mebbe this also has something to do w/the rfi... re: getting it to sync properly, it seems to be very sensitive to the digital cabling; believe it or not, i have had great success w/the $10 rat-shack 75 ohm cable. no sync problems at all w/my nad changer. but, i'm gonna try an apogee wyde-eye pro cable. (~$25 street-price) brianw sez it's the best, short of dropping $1200 on an fim digital cable... also, the digital input resistor is 100 ohms (pro audio, again?); i replaced it w/a 75 ohm resistor. you really need to do a few tweaks to the di/o, along w/hooking up that stancor. the thing, quite good stock, really responds to these simple mods. doug s. |
Hi Doug,
It is generating interference with my radio reception. Not unusual for digital products to do this (I've tried expensive ones that were worse in this regard), but it is annoying. Have to disconnect interconnects to it in order to listen to tuner w/o static. Was hoping that maybe the modifications do away with this and will investigate as you suggest. Still burning it in (it does improve each day) and waiting for the upgraded power supply (Stancor 3400mv) to arrive. Other things I've noticed is that it sounds best in the x2 mode; can't get any sound in ext sinc mode. Also, mine sounds a little better with the tube installed. I know the tube supposedly has nothing to do with the d/a circuit, but I notice the led's next to the tube warmth adjustment don't work unless the tube is installed and the sound is slightly smoother and there is less of the RFI mentioned above when the tube is installed. I won't comment on the sound until I have gotten the upgraded ps and it has run for a couple of hundred hours. |
sorry joe, i have no problems here... what is it doing? you may also want to go to the yahoo site set up for diomods; lotsa technically-oriented folk there, who may be able to help... doug s. |
Anyone have any RFI problems with their Art DI/O's? If yes, have you been able to solve them and how? |
Yep, the sound in our room was really green for most of the show.....The speakers had 75 hours on them and we had about that on the JC-1 prototypes and nothing even started to gel until late Thursday and Friday wherein the sound got to table radio standards.....I don't know where to point the finger on this one, but will have the JC-1s here next week to voice.....Have a friend close to me with some Wisdoms and they didn't break in pretty, but I expect a bit of both......Just in the talking stage right now on a preamp and trying to relate that the Blowtorch is a hot-rod and not easily built as parts have to be all dead matched to make it work properly, something that normally cannot be done in high volume production.....Ask again in a few months..... |
To Rcrump: I heard your preamp in the VMPS room and in your room at CES. I'm glad to hear you say the amps and speakers in your room were green, because that is how they sounded to me. Your preamp is transparent though. How much of the Blowtorch do you hope to be able to build into the proposed Parasound preamp, and will you hazard a guess about projected retail on it? |
My tastes in music are a bit unusual as I like live recordings made in small venues in front of an audience and most of what I hear at shows bears no relationship to the club experience whatsoever......Other than just the bass in the VMPS room I didn't hear anything I thought was even acceptable sound, my room included....It is really tough to make a system from several manufacturers gel as all it takes is one green component and the sound will go to merely acceptable on the fifth day after set-up from truly nasty the first day......We had green amps and speakers and the sound the last day was merely OK, but I still could not play the "A" list of my live folk, blues and jazz recordings........Heard lots of cannons from other rooms and we had to play things like the "X" Files soundtrack the third day as anything produced by real instruments or voices would peel the wall paper off the walls.......I don't think the average audiophile has gone through this sort of nightmare unless they have moved and bought some new components at the same time....The CES normally has just awful sound unless someone takes the time to set up an entire system, break it in and then move the whole thing to the CES as Brian did.....I've done this once and had wonderful sound from the get go, but it takes a herculean effort and glad that Brian did so well at the CES as he and Shirley's efforts were rewarded this year...... |
To rcrump: Did you hear any new music (CD's) at CES that stand out? (IE; Great sounding new discs?) |
I wasn't kidding as we really don't want to build many of the preamps as they are a real pain to build.....Parasound wants to hire CTC to do a preamp and we'll do the best we can, but it will need to be easy to build and probably need to be remote operated.....It will likely be ready in a year or so.....Oh, for those that wonder where I have squandered the profits from CTC we finally broke even at ten units and are now building Nos 14 & 15 for a couple of lucky individuals....We sure aren't doing this for the money even at the pricing we have required........ |
Bob Crump,
Thank you for having a sense of humor.
I hope you sell more preamps than you expect and maybe even can license your technology to a larger producer so it will eventually "trickle down" to more of us. The hi end industry needs people like you as well as those few who can afford to buy your products at list price in order for the rest of us to enjoy the level of sound reproduction we do. |
Sedond, no offense taken whatsoever as we built the preamp to see how far we could take it and never expected to do much more than build a few units and have something for reference use the rest of the CTC partner's lives.....Just finishing up the big JC-1 amps for Parasound and they mentioned that they want a matching preamp, but it is going to be tough to make an easy to build and cost effective preamp for them....It will happen this next year I imagine.....Back to Art it is possible to spend a lot of money on digital parts as I specified in the 1.5 rev to the Entec Number Cruncher as teflon caps don't some cheap nor do Muse caps, Schottky diodes, shunt regulators or Vishay resistors....You can run the bill up pretty high if you aren't careful and obtain better performance and finally come to a stopping point years down the way, but the point is the digital circuit is exactly the same electrically and most DAC chips just don't cost much these days..... |
Well, well, well:
I've been listening to my DI/O all morning, freshly modified by Bolder Cable Company and I have to say that I am floored by how good this DAC sounds. There is no question in my mind that it easily outmaneuvers my ModWright/Perpetual Tech P-3A. I am amazed at the purity of the treble, its delicacy, and fine focus. The bass also surprised me. It has clearly the most natural and detailed bottom end that I've heard from any DAC in my system. And the midrange is less opaque and oh-so-transparent. The DI/O, with Wayne's mods is clearly a winner -- and the thing is not even broken in.
I heard so much more detail from almost every cut in Fionna Apple's "When the Pawn" CD, that although I have played this recording countless times, it was almost like I was hearing it for the first time. A drum/percussion passage toward the end of her song "Limp" amazed me by how dynamic and true to life it was (very high slam factor). Later I put on the "O Brother Where Art Thou?" soundtrack and almost jumped out of my skin at the start of "Po Lazarus" because the sound of the prisoners cracking rocks in the opening was THAT STARTLING!
Happy Listening! |
hi bob, i in no way meant to slight your product or your efforts - i'd love to hear the blowtorch. preamps & amps (especially preamps, imo), are items that *can* be made to sound great w/lotsa time & money thrown at them... of course, it's way beyond my budget, & my comment was made cuz i really *do* think my preamp (not exactly cheap at its original retail of $4600), *is* an outstanding-sounding preamp, sonically competitive w/anything *i've* ever heard. of course, i have not had the opportunity to audition competition in my rig, where it matters most... regards, doug s. btw, i can't disagree w/you about your opinions of the cost of digital electronics... :>) |
Joe B and Sedond, it costs like Hell to build something right and we really don't want to build very many of the preamps anyway...I thought it was necessary to point this out as that was not a cheap system as the preamp cost more than the rest of the system combined.....Regarding digital I never have understood why it should cost so much as you can't do anything to the digital circuit or the thing won't work....About all you can do to any digital circuit is play with the supplies and maybe the quality of any trim caps and resistors.....All this refers to DACs as most transports can be updated with better clocks, output drivers and supplies..... |
re: the ctc blowtorch - way-expensive preamps may be worth something for those w/deep pockets, but i'm not so sure about expensive dac's... ;~) and, after i have a chance to audition the vmps rm-40's, i may have the same thing to say about way-expensive speakers, too! :>) actually, considering the relatively reasonable amount i paid for my melos music-director preamp, i'm not sure just *how* much way-expensive preamps really *are* worth... ;~) brianw - i'm curious - who, besides me, has said anything negative about the class-a op-amp biasing? and, since i've fixed the broken trace from the op-amp, i have to say the mod was an improvement... i agree that doing the internal voltage-divider mod so you can use any cables is a good thing, but you can also replace eight resistors on the board to reduce voltage - this is even better. instructions on how to calc the exact reduction you want are on a spreadsheet on the yahoo diomods site. ie: to reduce the units' output from 7v to 2.6v, replace 4.7kohm resistors r14, 15, 20, 22 w/13.3k resistors, & replace 4.7kohm resistors r16, 17, 21, 23 w/8.08k resistors. i just ordered resistors for this mod today, but w/a bit higher final output, at 3.2v. i will be yanking & replacing some resistors i just upgraded last week... ;~) doug s. |
I did notice that the CTC Blowtorch was part of the award winning system and previously have read a rave review of it. Next time I have $18K that I don't know what do with, I'll be in touch. However, if you should decide to sell them for $123 plus shipping, I might call a little sooner. |
VMPS used the Art D/IO into the 18K CTC Blowtorch full function preamp at the CES which nobody seems to have picked up on......
Bob Crump
CTC Builders |
The Chicago Audio Society did a "shoot-out" comparing the Art Dio to an Electrocompaniet all in one cd player. Of course, they used the Electro as the transport into the Dio. From what our newsletter said, the Electro was picked as sounding better WITHOUT the Dio hooked up. Then again, i think that this was a bone stock Dio, so who knows what would've happened after modifications. One thing is for sure, the ART is WAY cheaper : ) Sean
> |
I unpacked my freshly modified DI/O today and saw that Wayne returned all my old parts in a zip-lock bag. He replaces a lot more parts than I even realized -- IC chips, a lot of electrolytic caps, resistors, diodes, and the cheapo RCA jacks (digital & analog). I am impressed with the amount of work he did. All those parts together don't look like they'd physically fit inside the tiny DAC!
I'll have to get this little beast back in my system; possibly on Thursday, but definitely by the weekend! |
All I can add is that there is a HUGE difference between stock and modified. Albert Porter has sent his off to the same guy that modified mine for $140.00. The guy did all mods described at cfrasers site, minus the Class A mod, plus socketed the A/D chip so you can pull the chip disabling that circuit. He also placed the voltage divider internally so ANY digital cable can be used, as I'd like to experiment with better quality cables. I've heard both good and bad reports from those that have the Class A bias of the op-amp. I decided against it. After seeing what is done inside, I'd have to say that Waynes' price is more than fair. |
good luck, joe. re: soldering, really - w/a 30w iron & the $10 rat-shack desolderer, ya don't have to be an expert. as far as electronics knowledge goes, i'm basically an electronics illiterate, but i could still do it, cuz all ya have to do is follow instructions! ;~) every mod is clearly delineated as to what needs to be done... but, wayne at boldercables will do most all of 'em for ya, for $200... regards, doug s. |
Thanks, Doug. Your right. For $134, shipped, plus $12 for the connectors and adaptors, I figure if it stinks, I can sell it or throw it in my video sys for music. I know the separate voltage attenuator is not an optimum solution, but it will get me started and allows me to only change one variable at a time.
After it burns in and if it seems to have potential, I will either contact Bolder or see if Stan Warren is doing anything with these things. I am not very good with a soldering iron and it this modification stuff is beyond my limited knowledge of electronics. |
plato, bolder cables will offer a 5.4a p/s for $100. but ya might want to try your monolithic p3 p/s - that's supposed to be a nice p/s... kichoi, good for you - but, i *can* say that the mods i've done have taken the unit to a competely different level - even my wife can't believe this thing! ;~) so, whip out your soldering iron, or checkbook, & go for it! ;~) joe b, that's what happened to me - when i read of guys ditching their multi-kilobuck digital rigs after hearing the d/io, i figured for ~$130 shipped, i dint have a lot to lose, even if it sucked! ;~) and, even stock, it's nicer than that $3k resolution audio cd50, & i'm using a relatively inexpensive nad cd-changer as a transport... regarding upgrades, i suggest you look at harmonicdiscord.com, & go to the boldercables forum there, for what wayne offers - he has it all listed out. for more in-depth reading, & for diy info, go to http://www.interlog.com/~cfraser/DIO.htm here, you'll find everything you wanted to know about the d/io & then some. also links to where to get stuff, & a yahoo diomods site. re: that p/s, after i paid $30 to rat-shack for the stancor 3.4a p/s, i found one (atari 3.4a) at http://hosfelt.com/ for $5... ;~) you need a 9vac p/s, btw, not a vdc p/s... and, brian cheney insists that the best response is actually something like 10.4vac - he uses a couple-hundred-dollar variac to power his... as far as benefits to the mods... well, i have all the same mods as wayne's units, except i haven't switched the connections, or the attenuator resistors. (i *have* upgraded the resistors, tho, i just didn't change their values...) i use a jon risch derived resistor attenuator set-up in a pair of star-quad pro-audio cables w/a 1/4" fone plug on one end (w/room for the two holco resistors) & an rca on the other. find the cables here: http://www.soundprofessionals.com/cgi-bin/gold/category.cgi?category=250&item=SP-RCA-PHONE&type=store cheap, at $30/pair. if ya get 'em intending to solder in the resistors, be sure to tell them, so they won't solid-pot the 1/4" fone-plug end! :>) i have also done a mod that wayne doesn't do (yet!) - i have biased the upgraded lt1365 op-amp to run in class-a. and, there's another couple mods i may yet do - the main one being the addition of a transformer at the digital input, which is explained in detail on crag fraser's site. with mods, the sound, good as it was, improved in all areas - the liquidity is amazing, especially considering it is digital. and, it does *not* come at the expense of detail - you can hear *everything*. the soundstage depth has great layering. there's great dynamics, bass, etc... really! ;~) as far as your present cabling goes, if ya really wanna use your harmonic technology cables, i suggest you ditch those off-the-shelf attenuators (several folks told me they are a noticeable sonic degradation, when i inquired about using 'em), buy a pair of neutrik 1/4" fone plugs, & install 'em on to your h-t i/c's, w/the two resistors soldered in. later, if ya want to swap out the resistors internally, to acomplish the attenuation, then yank the resistors out of the cabling. or, just go for the whole enchilada all at once, either diy, or pay wayne at bolder cables... but, act fast - i think he's gonna be *very* busy for a while... ;~) the mods really aren't that difficult - w/a 30w soldering iron, & a special desoldering iron/bulb tool available from rat-shack, you're in biz. just order up all the correct resistors, jfets, caps, etc, & have at it! :>) even *i* was able to do it! i did run into a snag, damaging a trace when pulling out one of the stock op-amps, but the folks on the diomods site pointed me in the right direction to find it, and i was able to repair it no sweat. just *do* it! ;~) doug s. btw - let's not forget brian cheney & vmps - i hope to audition the rm-40s in the next week or so. this certified cheapskate may once again find the best value to be *new* vmps speakers - that certainly was the case w/my vmps subs! :>) |
Hi Doug,
I can no longer resist all of the publicity that the Art Dio has received and just ordered one today. I think I have an upgraded power supply somewhere in my attic that I can use or can order one from Radio Shack. Beyond the power supply upgrade, what else do you suggest be done and what are the sonic benefits of what you would suggest? I know Bolder has special cables for the DIO, but the Belden based cables I have tried (not Bolders) I did not like, so I bought adaptors and voltage reducers so I can use my Harmonic Tech cables for now. I hope this thing sounds good. |
ART DI/O even in its stock status is still the Gem of the Audio Gem. I use one with a 2.5A power supply, unmodified in my system with a satisfaction - a rare condition for anyone who's been blessed with the disease... |
Doug,
I just received my ART DI/O back from being modified by Wayne of Bolder Cable Co., and will be trying it in my system shortly. After seeing the list of mods he performs for that $200 price I have to agree that it's a very sweet deal indeed. I'll be putting mine up against a ModWright P-3A with level 1 mods. However, I have some other issues to nail down in my system before I can make a fair comparison.
I thought that the DI/0 held its own against the P-3A before the mods when driven by the Perpetual Tech P-1A (upsampled to 24/96) and using the Monolithic P3 power supply. So this comparison should be interesting. As you know, the DI/O does not perform upsampling on its own (the P-3A upsamples). I understand that Bolder Cable Co. will also be offering a heavy-duty power supply for the DI/O at a very reasonable price. |
