My philosophy is to build, modify, break, and improve.
The Coincident PREs can easily sound terrible, but they do let you hear every single change, from cables to capacitors and resistors to protective shrink wrap over cable terminations. They've taught me a ton as I've pulled more and more music out of them each step of the way.
Toggle equipment details for more information about each system component.
Coincident Speaker Technology Pure Reference Extreme with 99.99% Solid Core Silver Wiring & Duelund CAST High Pass Crossover
Very revealing. 94db efficient, with a flat 8 ohm impedance. Accuton ceramic drivers on the head units. Two 12" Peerless aluminum bass drivers on each sub.
A single 4.7uF capacitor provides high pass for the tweeters. The midrange connects to the amp through a single inductor. The bass units begin crossing over (via a single inductor, capacitor, and resistor network) at 125hz and play from 20Hz up into the bottom registers of the human voice. All crossovers are first-order/phase correct.
I have upgraded the high-pass capacitor to a Duelund Tinned-Copper CAST and it was a wonderful change. More clarity, better imaging, and more natural tonality over the stock Solen capacitors. I also replaced all binding posts with Wago high voltage pure copper wire clips and replaced all internal wiring with Tempo Electric solid core 99.99% silver in an oversized Teflon jacket (12ga for the bass, 14ga for the mid-range, & 20ga for the tweeters).
I augment my bottom end with a distributed bass array inspired by the Audio Kenesis SWARM.
The DBA is completed by four units, two 1.5cuft sealed subs featuring the same 12" Peerless XXLS (835017) drivers used in the Coincident PREs and two "Duke 32" wall-loaded subwoofers using the 12" Dayton Audio RSS315HO-4 driver. The system is run in a quasi-stereo setup by two Dayton Audio SA-1000 monoblocks, each amplifying a sealed sub and Duke 32" combo connected in series for an 8-ohm load. The sealed subs are located along the side walls of the room and the Duke 32s are in the front and rear corners. Each amplifier handles a single channel and all crossover (24db BW @ 67hz) and EQ duties are handled by a miniDSP 2x4 HD.
The "Duke 32" wall-loaded subwoofers are designed by Duke LeJune of Audio Kenesis and were purchased as kits from speakerhardware.com.
The subwoofer system is a key factor in overall system performance and the miniDSP is absolutely essential in allowing it fulfill this function.
Special thanks to Duke LeJune for encouraging DIY copying of his commercial design, and Linkwitz Labs, who's Thor subwoofer provided inspiration and eq guidance for the sealed subs.
First Watt F4 Monoblocks - "Special Edition" (DIY)
A premium DIY build with help from Nelson Pass and the diyaudio.com/passlabs community. Built with outboard power suppies using independent 400v transformers for both the + & - rails (1600v total), perfectly matched Harris IRFP9240 & Vishay IRFP240 MOSFETS, Vishay naked z-foil resistors throughout the signal path, VH Audio 28ga .99999 solid core silver input wire, Tempo Electric 14ga .9999 solid core silver output wire, 384,200uF of total power supply capacitance with inductor filters and 50uF film bypass capacitors, and pure silver WBT RCA connectors.
From the F4 manual: "The combination of a simple Class A circuit operated without feedback and the good objective performance gives us a superb sounding amplifier. The low distortion, bandwidth extension, and high damping results in midrange clarity, treble detail, and control on the bottom end. While these are available from most good solid state amplifiers, the F4 also brings depth, imaging, midrange warmth and top-end sweetness. Overall, it is one of the best sounding amplifiers, and if you can live with unity voltage gain in your amplifier, it is possibly your best choice."
Class AB subwoofer amplifiers with their own built in crossover circuitry (bypassed in the current setup). 500W into 8 ohms, 1000 into 4. Each runs two of the four subwoofers in the distributed bass array.
Currently unused, I also have a second First Watt F4 monoblock build with outboard power supplies and 144,000uF of total capacitance. They have a Nelson Pass designed BA-3 front end that provides additional gain in case a special use scenario arises (I previously used them to amplify single subwoofer channels).
A three-chassis, custom built, single-stage preamplifier designed around the EML 20A-M tube by Radu Tarta of Simple Pleasure Tube Amps. The 20A is a low-distortion, high-gain modern DHT tube and drives the connected amplifier through high-quality amorphous core Monolith LTA 01/25mA output transformers. The pre uses the beautiful mesh version of the 20A tube, solid core silver signal wire (VH Audio silver in cotton), Lundahl power supply transformers and chokes, cathode bias, and DC coupled inputs. All AC/DC conversion occurs in separate power supply chasses to keep noise out of the sensitive DHTs. Each channel has its own power supply chassis. Volume is controlled by a silent-running Tortuga ePot.V3 Mini with its own independent power supply. It uses a discrete resistor ladder to provide attenuation and balance control. A swappable hardware module allows switching to LDR-based attenuation, although it sounds inferior to the resistor module.
Audio Mirror Tubadour III SE with Duelund CAST Caps, WBT Ag RCA Connectors, and 99.999% Silver Signal Wire
A non-oversampling dac based on Analog Device's AD1865N-K R2R chip. An output stage that can utilize 5977, 6N1P, 6DJ8, ECC88, 6922 and 6H23P tubes. Upgraded with VH Audio's 99.999% solid core silver wire and WBT pure silver RCA connectors
Magna Mano ULTRA Network Streamer with 99.999% Silver Signal Wire and a WBT Ag SPDIF Connector
A highly modified raspberry pi based network streamer running logitech media server software. Low noise, low jitter, with a linear power supply. Lossless Tidal files are streamed via UPNP and fed to my DAC over a 1.5m 75-ohm VH Audio Pulsar pure silver digital cable. Upgraded with a WBT Ag 75-ohm RCA SPDIF connector and VH Audio 75-ohm solid core 5N silver wiring.
A huge added plus is that this system can be used to automatically record a history of everything you play. See my list here: https://www.last.fm/user/cal3713
VH Audio DIY 28ga Fine Silver RCA Interconnect (w KLEI Absolute Harmony)
Interconnects for the DAC -> Preamp connection. Built using VH Audio's "UniCrystal OCC .99999 Solid Core Silver Wire w/ Cotton insulation" wrapped around a teflon tube core in a double-helix design and terminated with KLEI Absolute Harmony RCA connectors.
A solid core silver true 75-ohm digital cable. 1.5 meters long to prevent the signal reflection issues that arise in shorter cables.
"The Pulsar Ag interconnect utilizes a single (unplated) high-purity, solid OCC Silver conductor of 24 AWG. The high-purity Silver conductor is produced by the Ohno Continuous Casting process, resulting in a single crystal structure, with none of the typical grain boundaries found with conventional processing methods."
.9999 pure silver solid core speaker cables in an oversized teflon jacket. Used as amplifier output wire and both external and internal speaker wire. Beautiful imaging and tonality with increased clarity and decreased distortion. Everything just sounds more real and natural.
High quality solid core silver combined with the low dialect constant of the oversized teflon jacket used without termination is an outstanding sounding combination. Other companies may sell you more advanced geometry, but they're not going to beat the raw wire quality. These cables deserve more attention.
The most beautiful tonality of any capacitor I've tried (Solen, Miflex, Jantzen Z-Cap, VH Audio TFTF, Jupiter Copper, ClarityCap, Mundorf Supreme, Mundorf Supreme Silver/Gold in Oil). Used as output capacitors in my DAC (1uF), former DS pre-amp (.47uF), and as the only component in the Coincident PRE high pass crossover (4.7uF).
Industrial power conditioner... a great improvement to the front end components, but must be installed in a separate room. Provides power to all components except for amplifiers.
(SOLD) Thiel CS 1.6
Paired with a Classe CAP-151 and fed via an Exemplar modified Denon DVD-2900.
(SOLD) Classe Audio CAP-151
Paired with Thiel CS 1.6 speakers and fed via an Exemplar modified Denon DVD-2900 with tube output stage.
(SOLD) Exemplar Audio Denon DVD-2900
A modified Denon DVD-2900 universal disk player with a tube output stage. The source for a Thiel CS1.6 & Classe CAP-151 system.
(SOLD) Thiel CS 2.4
Time and phase coherent speakers previously paired with a Pass Labs INT-30A and fed with a PS Audio Perfectwave DAC MkII.
(SOLD) Thiel Smart Sub SS1
Subwoofer used to add further extension to Thiel CS 2.4s.
(SOLD) Pass Labs INT-30A
Integrated amplifier previously paired with a pair of Thiel 2.4s and fed via a PS Audio Perfectwave DAC MkII.
(SOLD) Coincident Speaker Technology Super Eclipse III
Efficienct 16ohm speakers paired with Coincident Frankenstein 300b monoblock amplifiers and fed via a PS Audio Perfectwave DAC MkII.
(SOLD) Coincident Speaker Technology M300B Frankenstein MK II Monoblock Amplifiers
Wonderful 300b monoblock amplifiers, paired with Coincident Super Eclipse III speakers and fed via a PS Audio Perfectwave DAC MkII. Used with EML-XLS 300b power tubes.
(SOLD) PS Audio DirectStream & Perfectwave DACs
A Perfectwave DAC, upgraded to MkII, and eventually to a DirectStream. Used primarily with the Bridge II ethernet input. Paired once with my Coincident Frankenstein 300b/Super Eclipse III system, and once with my current Coincident PRE system.
(SOLD) Don Sachs Audio DS-2 6SN7 Preamplifier with 99.999% Silver Wire, WBT Ag RCA Connectors, & Duelund CAST Caps
Combined in a system with First Watt F4 monoblocks, Coincident PRE speakers, and an Audio Mirror Tubadour III SE DAC.
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Don's modification of the VTA SP-14 6SN7 circuit. Upgraded with VH Audio's 28ga 99.999% solid core silver wire in cotton, WBT pure silver RCA connectors, and Duelund Tinned-Copper CAST output capacitors.
@gryphongryph I will heartily recommend the AM to anyone who asks. It's a great dac. You can see in a post below (on 01.26.20) all the dacs I chose it over. Recently I bought a Holo May, which was great, but ended up sticking with the AM.
As to the extent to which it mates with a particular system. I'd say that it should be chosen by people who will pursue flesh & blood natural realism in their system, even at the expense of perfect reproduction or neutrality. It definitely isn't as accurate as the Halo May, for example, but it creates a more real 3-dimensional image in my system. It's also not as flat or extended across the frequency spectrum, so there's a bit of cost to get that wonderful illusion. I personally find that a small price to pay. It's also important to note that the exemplary Halo May was the first dac that really pointed out that limitation to me.
As noted above, I'm in transition and had to put the system in storage. I needed some way to explore new music while stuck on a laptop or mobile and started compiling a list of great musical performances with careful videography.
Unfortunately my system is in flux due to an impending move, so I don't have pictures or a writeup, but I commissioned a new "Shiny Eyes" DHT line stage from Radu Tarta at Simple Pleasure Tube Amps. It is single stage, transformer coupled design based on the high gain, low distortion EML20A (mesh) tube. Volume control via a Tortuga unit that allows either LDR or stepped resistor attenuation (and balance control).
@jond Thanks! And yes indeed. They're actually motor-run caps, which is why Ducati is involved, and the cheapest way to get larger value film caps for power supplies. They're 50uF bypass caps across the last of the big 24,000uF electrolytics.
@sysadmin & @jaytor Thank you so much for fixing the systems notification system! I really think it'll improve the audiogon community. Fingers crossed...
@jaytor Thanks! I've stopped by and seen the ones on your page too. They are also great. I'd love to hear your speakers in particular!
Getting into diy has really improved my experience so much. It feels powerful to be able to look under the hood of any piece out there and have such a better idea of how well it's engineered and whether it's likely to sound good. Plus the diy community is such a positive and refreshing group to interact with. People always sending each other free parts and just trying to be helpful. If only we had more of that in these parts...
@cymbop And yes, just a print of an ink drawing I picked up at a little hippie campout in Ohio long ago. I think the guy who made it was in his early 20s at the time. I hope he's still making art... it's really quite good.
@rixthetrick I've tried bypass caps a few times and had mixed results. I liked them (i.e., the same Duelund silvers you're using) over the inter-stage coupling capacitors in my Coincident Frankenstein 300bs, but found the effect minor. I also put them on the output capacitors in my Don Sach's preamp and couldn't hear any effect. And when I put them in the tweeter crossover I got some smearing of information and took them out. With the variable outcomes, I just decided to leave that option alone.
@noromance "Have". I bought those springs from a Chinese seller on AliExpress... $38 for a set of 8. They handily outperformed my isoacoustic pucks and now exist under my speaker head units, amps, and pre. I'm definitely a believer in spring based isolation.
It took me four years to get these speakers to sound like the reference they're supposed to be. A pain in the ass, but also a real learning experience and rewarding in the end.
Recently finished a dac shootout... had the Lampizator Amber 3, Audio Mirror Tubadour 3 SE, ifi iDSD pro, and Shiit Bifrost 2 on hand.
In my system, the Audio Mirror was the winner. To my ears, it was the most real sounding of the bunch. It has beautiful "meat on the bones" and was the most holographic. The Amber sounded good, but in a very different way. For me, it was brighter and more lively. The soundstage was huge, but had less depth and liquidity than the AM. I also liked the iFi iDSD pro (used in tube+ mode with the bitperfect filter). It had great tonality, but was significantly flatter and less 3-dimensional than the AM. I think more people should give it a shot. The Shiit was good. Very even-handed and competent, but more "digital sounding" to my ears. My friend was listening blind and liked it the second best of the group (behind the AM).
Despite its king-of-the-hill status in specs (see Audio Science Review), I did not enjoy the Matrix x-Sabre Pro. It was very quiet and clean, with a nice mellow sound, but also a bit "grey" and sterile. I also did not like the PS Audio Directream, which just sounded wrong in my system. It felt disjointed. I don't know what the situation is, but for some reason it doesn't work with my ears. Unlike others, I actually preferred the PerfectWave over it (twice - as I tried upgrading two times over a 4 year span).
All in all, it was great to finally listen to a wide range of sources, and I could enjoy most of the ones in the stable. The experience also brought me closer to my AM T3-SE. A beautiful, highly recommended dac.
@ivan_nosnibor Thanks Ivan. Still very much a work in progress, but the Coincident PRE's always provide honest feedback, which definitely rewards experimentation. And I like learning about the role of all the small stuff, like coupling & crossover cap effects. It's been nice learning that nothing about the gear is sacred... just people putting together materials and liking or disliking something about the sound.
@gibsonian I really like the DS. It's great and improved every part of my system. Haven't tried all that many pre's though. It's better than source direct and outperformed a hornshoppe "the truth" in my system. I'll never go back to source direct. Would love to try some more competitors though...
Thanks CY, much appreciated. My experience in building this system has certainly taught me that every component impression is *completely* system dependent, and I think the PSA DSD is a great example of this. Based on the reviews I simply can't contest that it must sound spectacular in some systems. For whatever reason it never did that in mine. I wish I knew what the key variable is. Perhaps it's just different brains/ears that are sensitive to different aspects of signal processing. Who knows...
In any case, I just got on the system page today to update it, and as you'll see, I finally moved on from the PWD.
I'm now using an Audio Mirror Tubadour III SE that I absolutely love. Given that I've moved on to solid state amplification, I think having some tube sweetness in both my source and preamp really brings the system together.
Also, this dac is just fabulous with a wonderful tone and amazing imaging. And I like that it's based on an old chip so I don't have to obsess over every new product. I'd still love to hear some of the modern DACs from Mytek and Bricasti to see what they sound like, but am incredibly happy with the Audio Mirror.
UPDATE: Replaced my MIT XLR interconnects for the DAC -> Preamp connection with VH Audio's DIY silver interconnect. Built using VH Audio's "UniCrystal OCC .99999 Solid Core Silver Wire w/ Cotton insulation" wrapped around a teflon tube core in a double-helix design and terminated with KLEI Absolute Harmony RCA connectors. See: https://www.venhaus1.com/diysilverinterconnects.html
A wonderful upgrade over the old cables. Just more real sounding... and it lets me bypass a transformer in the preamp.
@r_f_sayles Indeed. Brutally revealing is certainly a proper descriptor. They let you know about every mm of the chain. I'd love to hear more about what you've built around yours if you've got the time to post details (here or on your own page).
And certainly the Duelund caps are a great step in the direction you want to go, really highly recommended. Do be careful attempting to remove the midrange. When I bought my pair they were damaged in shipping and I had to replace a midrange driver. I simply could not get the thing to budge and just ended up cutting out the ceramic layer so I could get my hands directly on the metal supports to pull it out. It was still incredibly difficult.
The tweeters are much easier to move around, but unfortunately that opening won't be big enough to get many high end capacitors inside the cabinet. I think the Duelund's will fit in the bottom of the cabinet because they're flat (Jupiters and other large cylinder styled caps will not) but I have not tried because I had so much trouble removing the one midrange.
On the plus side, getting the cap into a quieter external environment is supposed to be a plus...
Anyway, please do post more details about your PRE journey if you've got the time.
And sorry, power cords are 12ga Furutech FP-S032N based power cords from member Grannyring's Acoustic BBQ line. They've got Chinese copies of the furutech carbon/rhodium connectors. He sells for cost plus a small labor fee (and commented below if you want to contact him for a cord). Makes highly regarded Duelund-based interconnects too...
@scott_wolff Thanks, wish I'd tried them, but I didn't do anything besides the duelund vs stock comparison. I've actually pm'd a couple other owners of the PRE's, and it's a pretty strong consensus that the Frank's don't provide enough power. Both of the other two had purchased and sold Frankenstein's as well. Both recommended amps with at least 30 watts...
@islandmandan Looks like I'm on the right track, just read this from zen mod at diyaudio in discussion the m2 (he designs his own pass inspired amps and gets rare parts directly from Nelson):. "if you have F4 handy - just insert appropriate xformer"
@islandmandan Honestly, if my speakers were run properly with a 300b I'd still be using the Frankenstein's. Unfortunately they suffered at the frequency extremes (lack of bass and distortion up top) due to the mismatch. The F4s fixed those issues and the system improved as a result.
Not sure you'd find much difference in result of F4 vs M2. I haven't read a ton about the M2, but it appears to be similar to the F4 (i.e., uses the same mosfets, but only 2 instead of 6 per channel). That must mean it has a lower current capacity despite identical power ratings? It also provides 15 db gain with a transformer on the input, vs the lack of a gain stage for the F4. Should mean that the F4 is more transparent, but also a more specialized amp. Unfortunately I'm not a circuit expert, but that all suggests to me that unless either current or transparency were your problems with the M2, then you'd probably still prefer your 300b.
Of course if you'd just like an additional amp around for flavor (and comparison), then $800 gets you a great one.
@grannyring Thanks for all your input! You saved me so much money and improved my sound by pushing that beautiful Duelund wire. And I love the Duelund tinned copper cast capacitors. I didn't get to hear them fully when I was using them as coupling caps in my Frankensteins... they sounded nice, but also sucked out some of my bass, which made me a little gun shy about buying more.
As you noted, I did try the Duelund bypass caps on the output capacitors of my preamp, but actually couldn't hear any impact and sold them to Dave @ ZenWave Audio. Tried them on two sets of caps and wasn't able to hear any difference at all. Very different from when I added them over the Solen coupling caps in the Franks. They went in and never came out until I had to sell. Had to pull them and the upgraded tube set to make the price low enough for someone to bite...
Thanks again for all your help. Also, your power cables are great. I hope people are keeping you busy purchasing your wonderful creations...
@thosb Thanks for the compliments... wish I could say it was a purposeful journey, but it certainly feels very unplanned. I guess that's why I ended up with the strange, non-traditional equipment combination.
@islandmandan Also, when I sold off my Frankensteins and associated tubes, I got around $4500 back in the account. The pair of F4s cost $1600 and are essentially the same quality as the actual First Watt units (assuming sufficient building skill). $1600 for a pair when a single cost $2400 new? Just a crazy good deal...
I'm going to build some DIY SIT-3s this fall, mostly because it was fun to build the F4s and will be entertaining to try another amp. Once you build one First Watt clone, you can reuse everything (case, power supply, etc.) and just replace the old amplifier circuit boards with the new ones. That's what Nelson Pass does at the company itself.
Hi Dan. You can order the circuit boards, power supply boards, & chassis directly from the DIYaudio.com store. Unfortunately there's no standard kit, but the parts list isn't too crazy. I can e-mail you a spreadsheet with all parts sources listed. It's also posted here: https://www.diyaudio.com/forums/pass-labs/234355-guide-building-pass-f4-amplifier-134.html
If you go to the first page of that thread, you'll see the full build guide. It's so well done, that you're basically building adult legos.
Also, I'd be happy to help with ordering or parts questions if you decide to take the plunge. I'd never built any electronics before making an F4, and it was very doable for me. With all parts, it costs around $800 to make one. Such a steal for a wonderful amp.
@islandmandan & @jond. Thanks for the comments. Prior to this year I didn't really trust myself to open up any equipment, but thanks to a UPS/Fedex drop of my speakers, I was forced to learn. I'm so glad I did. That set me down a path that resulted in my amplifier build and my modification of every other piece of gear I own. It's so much harder to hurt a component than I ever imagined, and learning about what's inside and how it impacts the sound has been incredibly rewarding. I can't recommend it enough.
