It is the magic conjunction of relays exactly at 65 that emits the spiritual burp.
Might be fun to untangle the logic of seven relays to see how 65 is created. Might be all seven or might be zero.
BTW, that gizmo might be a perfect solution to a problem many have. When you have signals to amps coming out of a Behringer DSP or when the music comes from a computer. The best trick is to control them after they exit the DSP (lets the DSP run at max bits while you have a nice remote in your hands to control 2 or 4 amps in identical steps... like with extra boards inside the box). I made a little box with 4 Bourns ganged pots, crude in comparison.
Might be fun to untangle the logic of seven relays to see how 65 is created. Might be all seven or might be zero.
BTW, that gizmo might be a perfect solution to a problem many have. When you have signals to amps coming out of a Behringer DSP or when the music comes from a computer. The best trick is to control them after they exit the DSP (lets the DSP run at max bits while you have a nice remote in your hands to control 2 or 4 amps in identical steps... like with extra boards inside the box). I made a little box with 4 Bourns ganged pots, crude in comparison.
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Looks nice though mixed messages in that Ebay ad. 50K is high for an unbuffered passive 'pre'. It also can't maintain a constant impedance to sources since at higher volume settings the downstream power amp's input impedance begins to appear in parallel with the pot. Whether any of that matters will be system dependent.
Agree with bentoronto. 64 is 2**6, too coincidental a binary number. It's possibly the combination of relay logic. If it is completely passive testing with an ohmmeter between output and ground while switching volume from 60 though 70 with an empty input selected might give a clue.
Agree with bentoronto. 64 is 2**6, too coincidental a binary number. It's possibly the combination of relay logic. If it is completely passive testing with an ohmmeter between output and ground while switching volume from 60 though 70 with an empty input selected might give a clue.
I’ve used the twisted Pear unit - Volumite/Joshua Tree with a remote optically controlled Linear Alps pot to drive the Omron relays. Its good
I now use the Bent Audio volume control which ises totally silent Pickering reed relays from the UK. A balanced Bent Audio relay version is expensive. I won’t even talk about resistor types.................
I now use the Bent Audio volume control which ises totally silent Pickering reed relays from the UK. A balanced Bent Audio relay version is expensive. I won’t even talk about resistor types.................
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I used to use one of these but I reverted to a 2$ Alpha pot.
Resistor volume control 256 steps unbalanced stereo w/ highly reliable relays !! | eBay
I like the rainbow ribbon cables
Resistor volume control 256 steps unbalanced stereo w/ highly reliable relays !! | eBay
I like the rainbow ribbon cables
With all the time at home there should be a minimum 2 new projects per attendee at the next meet. (only after a proven vacine).
I’m finishing the jfet phono stage I’ve been working on for a decade ( or more) that matches the dac and preamp I brought last year. Now to get the turntable running.
I plan to try Bob Cordells / Rick’s Hafler driver board on a Perreuax Hitachi lateral mosfet amp later in the fall - hopfully its stable .......
Hope you remain well.
I’m finishing the jfet phono stage I’ve been working on for a decade ( or more) that matches the dac and preamp I brought last year. Now to get the turntable running.
I plan to try Bob Cordells / Rick’s Hafler driver board on a Perreuax Hitachi lateral mosfet amp later in the fall - hopfully its stable .......
Hope you remain well.
Since covid, I built a tube integrated amp and my take on the de-lite amp from Nelson Pass... Mine is a hybrid using tubes for VAS and a single MOSFET as a source follower using a 300W light bulb as the load. Amazing sounding for an amp with no gnfb
I'm trying to decide if I want to make an all in one integrated now. My current ones use a separate PSU.
I'm trying to decide if I want to make an all in one integrated now. My current ones use a separate PSU.
Hello folks,
Dave, I have found two that have signed up as beta testers trying out DH-220C in a DH-500 chassis. For the Perreuax, using three output pairs, I suggest to use the P230 output stage containing the extra supply filters and Zobel networks. Not sure how it would fit mechanically, but something to consider. Could help with stability. Bob has evaluated DH-220c in a P230 chassis successfully. It has three o/p pairs.
Another beta tester wired up a DH-220 as a mono-block, drove four pairs using one driver and both heatsinks.
Stay safe everyone
Cheers
Rick
Dave, I have found two that have signed up as beta testers trying out DH-220C in a DH-500 chassis. For the Perreuax, using three output pairs, I suggest to use the P230 output stage containing the extra supply filters and Zobel networks. Not sure how it would fit mechanically, but something to consider. Could help with stability. Bob has evaluated DH-220c in a P230 chassis successfully. It has three o/p pairs.
Another beta tester wired up a DH-220 as a mono-block, drove four pairs using one driver and both heatsinks.
Stay safe everyone
Cheers
Rick
Rick,
The Perreaux’s mechanical layout won’t allow me to use the P230 Output board.
i’ve added additional multiple power supply decoupling caps right at the output devices, and the output zobel is right at the output devices. The Perreaux pc board lets me use paralleled film/foil caps for high current zobels. The output choke is 12 gauge solid core. I may have to tweak the choke and caps once I test, but October maybe
The power supply was 2 x 18,000uf /100 volt caps, but I was able to fit a soft start, a Quasimodo snubbed Hexfet bridge, and made it a CLC with 2 x 56,000uf .47mh chokes and 2 x 18,000uf and it looks totally stock. A separate small transformer powers a DC protect board and the turn on delay speaker relay.
I just need to build up new driver boards and test it with single devices and then move to the output triples. But 2 front end projects to finish first.
Dave
The Perreaux’s mechanical layout won’t allow me to use the P230 Output board.
i’ve added additional multiple power supply decoupling caps right at the output devices, and the output zobel is right at the output devices. The Perreaux pc board lets me use paralleled film/foil caps for high current zobels. The output choke is 12 gauge solid core. I may have to tweak the choke and caps once I test, but October maybe
The power supply was 2 x 18,000uf /100 volt caps, but I was able to fit a soft start, a Quasimodo snubbed Hexfet bridge, and made it a CLC with 2 x 56,000uf .47mh chokes and 2 x 18,000uf and it looks totally stock. A separate small transformer powers a DC protect board and the turn on delay speaker relay.
I just need to build up new driver boards and test it with single devices and then move to the output triples. But 2 front end projects to finish first.
Dave
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Anyone in the GTA interested in joining the group buy for Cinemag SUTs (step up transformers)? I can have the units shipped to me and arrange local pickup to save on shipping. Please PM me by Sept 13 (Sunday) if you are interested.
Cinemag 1254 SUT Round II
Cheers,
Stephen
Cinemag 1254 SUT Round II
Cheers,
Stephen
Why I love DIY audio
Today completed a minor upgrade to my main system by swapping some caps.
I built using Russian PIO coupling caps throughout to make a system on a budget. Always thought I could one day upgrade. Same with Solen film caps on speaker crossover.
Parts ConneXion is running a 25% sale on film caps in Sept. Did a little reading on the shootout reports and chose Obbligato Premium Gold as a budget upgrade. Now 47uF in the speakers. Instantly improved. Then the 1.5uF coupling in the tube stage of the DAC. Another win. Finally all the 1uF inter-stage coupling caps in the tube amps.
The Russian PIO crossed with Russian silver mica were a totally acceptable solution but the Obbligato are in a different league without spending crazy $ for something like Duelund or VCap. Similar sound, but just a whole lot more low level information. So a lot more depth and space in the sound stage. Does not sound like it needs a lot of break in, but likely will loosen up with 100 hrs.
So that's why I love DIY. If I was buying commercial stuff and heard something that made this much difference I'd be happily dropping a few $k to swap gear. But DIY a few hours of reading and a little work and you have a whole new sound experience.
Today completed a minor upgrade to my main system by swapping some caps.
I built using Russian PIO coupling caps throughout to make a system on a budget. Always thought I could one day upgrade. Same with Solen film caps on speaker crossover.
Parts ConneXion is running a 25% sale on film caps in Sept. Did a little reading on the shootout reports and chose Obbligato Premium Gold as a budget upgrade. Now 47uF in the speakers. Instantly improved. Then the 1.5uF coupling in the tube stage of the DAC. Another win. Finally all the 1uF inter-stage coupling caps in the tube amps.
The Russian PIO crossed with Russian silver mica were a totally acceptable solution but the Obbligato are in a different league without spending crazy $ for something like Duelund or VCap. Similar sound, but just a whole lot more low level information. So a lot more depth and space in the sound stage. Does not sound like it needs a lot of break in, but likely will loosen up with 100 hrs.
So that's why I love DIY. If I was buying commercial stuff and heard something that made this much difference I'd be happily dropping a few $k to swap gear. But DIY a few hours of reading and a little work and you have a whole new sound experience.
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Why I hATE DIY audio - a rebuttal of sorts
OK, wear your funny hat here.
Three years or four years ago - time flies - I had sworn off making more stuff.
I figured things can't be that much better and I need to just listen and enjoy and forget about the equipment merry go round.
Then one December evening, I had noticed how " reasonable" a DAC board could be. Heck I did not know the difference between an ESS9038Q2m and an ESS9038Pro. But that DAC board for only $39 sure looked attactive. All I needed was a dual 15V power supply and I had an extra one in the parts bin which actually was small. So I decided I would "try" that. ...and I could empty my parts bin. Seemed like a plan.
Then the Dac board was a popular one on diyaudio and I learned of the mods that could be done. Oh Oh.....like a junkie getting another fix.
So after frying that $39 DAC, I elected to go bigger or go home. Then I started playing with all sorts of LDOs, clockc, new op amps. Now my "spare parts bin is bigger than ever. I have so many things that are new now. More chips amps, DAC, preamps, head amps, 3xTPA 3116D2, TPA 3251 etc etc. all because that DAC board for $39 got me going. DIY audio adds up when curiosity comes calling.
So did I enjoy it, yeah, but it really adds up. Don't do it for "saving" money. It's a drug.
OK, wear your funny hat here.
Three years or four years ago - time flies - I had sworn off making more stuff.
I figured things can't be that much better and I need to just listen and enjoy and forget about the equipment merry go round.
Then one December evening, I had noticed how " reasonable" a DAC board could be. Heck I did not know the difference between an ESS9038Q2m and an ESS9038Pro. But that DAC board for only $39 sure looked attactive. All I needed was a dual 15V power supply and I had an extra one in the parts bin which actually was small. So I decided I would "try" that. ...and I could empty my parts bin. Seemed like a plan.
Then the Dac board was a popular one on diyaudio and I learned of the mods that could be done. Oh Oh.....like a junkie getting another fix.
So after frying that $39 DAC, I elected to go bigger or go home. Then I started playing with all sorts of LDOs, clockc, new op amps. Now my "spare parts bin is bigger than ever. I have so many things that are new now. More chips amps, DAC, preamps, head amps, 3xTPA 3116D2, TPA 3251 etc etc. all because that DAC board for $39 got me going. DIY audio adds up when curiosity comes calling.
So did I enjoy it, yeah, but it really adds up. Don't do it for "saving" money. It's a drug.
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Fine rebuttal
I think we've all had those thoughts and you capture it well.
Your comments apply equally to why I hate audio as a hobby. Imagine if your curiosity was evolving a well refined system, but your level of granularity was a box purchased from the Hi End Audio shop. That's a real thing for a lot of people. I can't imagine how much that could cost. I'd rather have a drawer full of caps and op amps than a closet full of fully depreciated commercial gear.
Nice looking components you have built BTW.
I think we've all had those thoughts and you capture it well.
Your comments apply equally to why I hate audio as a hobby. Imagine if your curiosity was evolving a well refined system, but your level of granularity was a box purchased from the Hi End Audio shop. That's a real thing for a lot of people. I can't imagine how much that could cost. I'd rather have a drawer full of caps and op amps than a closet full of fully depreciated commercial gear.
Nice looking components you have built BTW.
Well, this is what I have to say. The Modulus 86 completely shocked me as I was NOT expecting it to be that good. It is now immediately in my main system now.
The punch, clarity and detail but NOT sterile and clinical or bright. Totally noisefree. It's only running on 28 Volt rails but it sounds much more powerful than that. It does not compress as it is turned up. So it never sounds "loud" and there is no indication the limit is approaching...it is easy to overdrive because it always sound effortless until the limit is reached. That's the downside of a low power but powerful sounding amp. Good thing I no longer listen loud. It replaces a 100lb beast of a power amp.
It is being driven by me LME49600 and LME49710 hybrid head amp as a preamp. The modded DAC, ESS9028Pro has been transformed. I was about to keep a Topping D90 but there was always that roughness and lack of body and dimensionality in female vocals. This forced me to finish up my mods of the 9028pro. In the end, I returned the D90 with MQA and kept/finshed my generic Ebay ESS9028PRO.
Again, when I consider the total money invested in the modded DAC, it probably approached the cost of the Topping D90. It was a learning experience.
So in conclusion, my system has dramatically improved since 4 years ago. The DAC is about the same size since the current stack with an external power supply case replaces an Assemblage DAC2 stack with a jitterbug.
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