That must put out gobs of watts.I know this and the value of it, thanks.
Can't sleep (doesn't help pup is emitting stifling unpleasant flatulence, ha) and I have been, was looking to see if have a pre amplifier (considering Lingwendil's comment might also apply to pre). Leads to more questions, will look over the Purifi / Hypex thread and see if clarifies what they are. Do see the Universal Buffer can also be used to supply XLR to the 86, interesting.
Edit. Found not only the answer, found additional information: https://neurochrome.com/pages/the-ultimate-guide-to-preamp-design. Very well written with nice schematics.
Yes, I saw that, why I asked.
If the DISSIPANTE 2U is recommended for the 186 and the 86 fits the same size, then why, other than holes, would one select the Modulus chassis? Ditto for thePurifi / Hypex case.
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OPS= Output Transformer,the MOST critical part in a valve amplifier.My maternal grandfather worked his way up to major in the Army Signal Corps during World War Two, in the Pacific Theater. He worked hard and built businesses, however, not telling or teaching his wife, it is now all gone. Additionally, I been dealt an unfair hand: Autism and parents divorce. I could b*tch and moan about it, or I can decide to work towards positioning myself; I have chosen the latter. I have gotten my last back payment (which is way less than the award letter specified) and required to spend it down in nine months. Instead of being stupid either way, find a middle position, that most importantly enhances the business I am trying to start and hopefully pass onto the next generation plus provides for my mental health and well-being (music is so important, even saved my life). In short, the trick is figuring out how to get out of the soup kitchen line and position yourself well.
What does "OPT" mean? Google wan't much help.
I think I am understand this, fairly simple, and not my dream amplifier :
https://drive.google.com/drive/folders/17jRI1lE_Vf9_Pq64LbT-PHy3pLpW1vuj
Plus, there are 12 videos on the building of it.
Can you please help with learning how to scavenge?
I mean this with all the love in my heart, but Pass is not as low distortion as something like the Modulus setup. But, they are different design philosophies. Cost has nothing to do with it, in fact it seldom does in the high-end audio world, no matter how folks try to market otherwise.
Bass is much tighter on the Modulus, for one, and the overall THD is lower. Doesn't account for all of it, but I've for sure noticed a trend with low THD having a more accurate sound and feel overall. Too much THD (even primarily 2nd harmonic) isn't something I tend to like. Not to say the THD on pass designs is excessive, but it's more of a boutique approach with some compromises for the design philosophy.
Yes, I found out price doesn't always mean quality a few pages ago with the Modulus design, makes me wonder if the same for moving coil cartages (in that buying at the low end doesn't have much difference to the high end). The vibe I got from Steve Guttenberg's interview of Nelson Pass was his designs should have been a value for the cost. Could be, folks are all individual. There is also Tom working hard to keep product in stock, being part of the community here, and helping folks make a decision even if means less profit.
Interesting the distortion is lower and the base is more controlled, with an over all more accurate feel and sound. Not only is an accurate sound is where I am now aiming for (versus aiming for distortion, aka over tube sound), also desire better base (I really love classical organ music). This is why plan to bi-amp, can put the 86 driving the woofers (acting as the main speakers) while the mids and highs are driven by tube amplifier. Plan anyway.
Will interject a funny here about base. So at worship practice yesterday I found all the soundboards sliders all the way down (supposed to be left alone), so as they were practicing, I was adjusting. Not having ever had to make significant changes, used 0 for a starting point. Trouble was when I did that with the base, caused one lady's glasses to vibrate and distract her, while the pastor felt like his teeth were being rattled out of his head. Oops, a bit too much base.
(As I am typing I am laughing hard, tears running down my face.)Ah, kind of like the difference between sweet tea made with boiling water and sun tea, both get you sweet tea, though the latter can be tainted if not done right. I am surprised and taken back a design would intentionally desire some distortion, my understanding is/was less distortion is better.
So Nelson Pass and those enjoying his equipment might not be able to hear the distortion?
I understand. Though the best we can do buying off the internet is go by others experiences, I don't know of any sound stores in Arizona, though have not looked hard. Even if there was, variety might not be had.
It is 0.00002%: https://neurochrome.com/products/modulus-86.
So then what comes next?
I don't understand the question.Yes, I saw that, why I asked.
If you want your Modulus-86/186/286 amp enclosed in a nice chassis you can buy the Modulus Chassis. If you want your Purifi/Hypex amp enclosed in a nice chassis you can buy the Purifi/Hypex Chassis. If you would rather build your own chassis, you can do that too. The ones by ModuShop are usually what I recommend. The BZ4309 available from several sellers on ePay is a good option too. If you'd rather build a nice wood (or metal) chassis you can do that too. It's DIY, right...?
My customers started requesting a chassis so I designed one, invested an ungodly amount of money in custom machined aluminum, and now offer them on my website. Not everybody is comfortable with CAD or dealing with manufacturers (even though Gianluca at ModuShop is great to work with). I add value for these people by having the chassis available for purchase.
Is your question about why I don't offer three chassis, one for each Modulus amp? It's pretty simple. The heat sinks on the Modulus Chassis are large enough to support the Modulus-286 (which dissipates the most power), so they will support the Modulus-86 and -186 as well. I can't go lower in height or the power supply won't fit. Given that the chassis can physically support all three amp types, I might as well have the holes drilled for the three types and make the chassis universal. That allows me to make the smallest investment in aluminum and get the greatest return on that investment. Keep in mind that I'm investing $10k-ish at a time here for a relatively small stack of chassis. That might be pocket change to you, but to me that's a lot of money to tie up in custom machined aluminum.
Exactly. Pass is pretty open about this. He designs for high-ish even order distortion and also a steady decline in the harmonic content for the higher harmonics. He says that's Audio Nirvana and has convinced many people that this is the case. Good for him.
I design for the lowest possible distortion for a couple of reasons. Firstly, a low-distortion amp sounds good with all music types. This eliminates the need for voicing or selecting amps for certain music styles. The drawback is that a precise amp will not mask flaws in a bad recording. If you feed crap into the amp, amplified crap will come out. That's how amplifiers work... Secondly, the error correction I use in the Modulus amps improves many other performance parameters in addition to the distortion. The Modulus amps have vanishingly low IMD for example. Humans are much more sensitive to IMD than to THD, so low IMD matters. The error correction also greatly improves the PSRR of the amp, which means the amp will sound good regardless of the type of power supply. You can even put two channels on the same power supply without issues.
Once you get above a certain point that's certainly true. Cost matters in the <$500 or maybe <$1k space. It matters much, much less (if at all) in the >$10k or >$100k space.
That's been my observation as well.
I would probably push it another order of magnitude to have some margin. I would also add that harmonic distortion is just one distortion type - and probably the least offensive one at that. IMD is more important. You want both to be inaudible across the audible frequency range at all power levels below clipping.
I see where you're coming from but I still disagree with you. Have you ever had the ... um ... "pleasure" of listening to heavily distorted hold music? That's what 4 kHz bandwidth and 10% THD sounds like. Widening the bandwidth to 20 kHz and reducing the THD to 0.001% (-100 dBc) are not just engineering feats. They bring real benefits too.
Improving further to, say, -120 dBc may be an engineering feat. Whether it has a subjective benefit can be debated, but if it also improves the IMD I would say that it is an engineering feat that has a real benefit. Too many get target fixation and look only at one spec. I keep stressing that we should look at many specs and not just one. Just as an airline pilot looks at the information from many instruments and not just the altimeter.
I would further argue that if you use a DAC chip with -120 dBc THD and you're only able to get -80 dBc THD out of your finished product you've blown it. That's crap engineering in my view. On the other hand I'd take it as a sign of good engineering if you show, say, -118 dBc for the finished product. The closer your product performs to the ideal use case highlighted in the DAC chip data sheet the better the engineering.
Tom
Of course. But sometimes it does. Problem is sorting out the wheat from the chaff, as it were.
Right, when accurate sound is the aim then measurement needs to be made on the acoustic output. There are ways to reduce speaker distortion using distortion cancellation technique, not perfect but better than doing nothing.
It is often forgotten that amp distortion does not correlate linearly with distortion of acoustic output. Lowest distortion amp is great for low distortion electrostatic panels, but used with dynamic speakers left driver generated distortion untouched. However, some people loves the distortion sound of their speaker so much they like to keep it as pristine as possible.
Tom - If you haven't already seen this, you may be interested in my THD Challenge.
I chose a spectrum that makes THD easy to detect.
Some people can detect 0.01%, but it is hard. The main limitation is the background noise level. A really quiet room is needed to hear a harmonic at -80dB. No-one could hear -100dB.
Ed
I chose a spectrum that makes THD easy to detect.
Some people can detect 0.01%, but it is hard. The main limitation is the background noise level. A really quiet room is needed to hear a harmonic at -80dB. No-one could hear -100dB.
Ed
On the 186 product page, it provides a link to the DISSIPANTE chassis, where the 86 product page does not provide any information. This was misunderstood as the only chassis that would work be the Neurochrome chassis. Furthermore, there is the significant difference in price and I was asking what this additional cost supplied (ex. the holes).
I live alone (unless count the dogs, however, never commented about my design aesthetic
), no one ever comes to visit, and I prefer function over form. Almost to where if a spam can suffice, use that, however, doesn't have heat sinks, so don't take this analogy seriously. That makes sense. Interesting some manufactures can be tricky or challenging.
The only CAD I know that apply is AutoCAD (back about 10 years ago found free version of Sketchup changes dimensions by some infinitesimal amount and then the dimensions come out really odd).
Having taken some business classes, know any investment is a risk, the greater percentage of total assets invested means a greater risk.
In response to what you said, it is a small SSI back payment that is providing the opportunity. Per SSA rules, the money has to be spend down by nine months, so invest most in the business I am trying to start and a small portion into music (side note, if damaging speakers with too much wattage seems a wiser use of money to create a system of lower output). See, with SSI about $600 a month, there isn't any ability to spend other than the bare essentials. So no, $10.000 is a huge sum of money.
Seems then the difference in cost is scale of production and athletics. Am I misunderstanding?
Myself would prefer this, listen to a very wide range of music and suspect a lot of folks do too. Seems kind of ridiculous to have multiple systems to enjoy multiple kinds of music.
Myself would see this sometimes as an advantage. Take for example Sir Paul McCartney's first album "McCartney." What makes it special is it is the first lowfi album mass produced, remained number two in the UK for three weeks. Hearing background noises expresses its time and place.
Learned something new, thanks.
Notice I used the word "value."
To sort this out, we are fortunate to have this forum, partly for feedback and partly for help building kits which makes obtaining better equipment at a lower price possible.
It is often forgotten that amp distortion does not correlate linearly with distortion of acoustic output. Lowest distortion amp is great for low distortion electrostatic panels, but used with dynamic speakers left driver generated distortion untouched. However, some people loves the distortion sound of their speaker so much they like to keep it as pristine as possible.
I had considered electrostatics, however, at the cost for new is quite high and shipping used isn't inexpensive. Additionally, the space I am currently in doesn't have a whole lot of wall space plus one possible position mean one speaker's distance to the wall be different than the other (concern be audible difference between left and right) and the other position put the backs facing the kitchen. Additionally, they are particular about amplification, not sure my SU-Z600 could drive them, probably. One of Tom's amplifiers could, not sure which though.
The drivers I am considering have a SLP of 97dB, would this not come close to this?
I am Autistic so I was curious what happen. Grabbed my Koss Pro/4AAs (for those that don't know, they are studio monitor headphones) and was surprised at some frequencies could hear the 0,001%/-100dB. Clearly anything below 0,01%/-80dB is nice, though not necessary. Anything below 0,001%/-100dB then seems pointless. Just my humble opinion based on the experiments results.
I would need to barricade the neighborhood streets to have a chance of hearing -100dB.
Oh dear. My sympathy, I used to live in a noisy neighborhood in a house sided in 1/4" fiberboard, barely any insulation, and single pane windows. I didn't realize how much affected me until moved into this place with modern insulation, stucco finished exterior, and double pane windows, far, far, fewer episodes of sensory overload. I measured it in the past, inside it is about 35dB. I don't know how folks can live in a big and busy city, like New York, never mind folks living piled onto each other.
I get it. I am SSA representative payee for a 100% disabled person. Know all about how the system works, difference between SSI versus SSD, etc. Sorry to hear about your situation. Considering that, I think you are in pretty good hands with the guys you are talking with here in this thread.
OTOH if this thread was about the real truth of human hearing and of typical audio measurements, beliefs about the two, unspoken assumptions people make, etc., I would take a harder line. As is, believe you are in the right place to find good value.
Please take care.
Interesting, good to know.
Just so we are clear, I believe I am very fortunate. I was told I must have a representative payee (discussed this with my then girlfriend's mother who broke the promise she initiated and caused a beautiful eight month relationship to end, we were an amazing fit) then they changed their minds, nice not having someone burdened with it nor in charge (had to make my brother trustee of my Special Needs Trust and now that he is not talking to me, not sure how get the bank statements SSA now wants). Additionally, SSI allows me to work towards self employment and as a safety net. Plan to have competitive prices as not as necessary to charge top dollar, plus, I want re-upholstery to be more affordable so done more, both for environmental benefit and the emotional benefit (ex. friend is at a point in her life where to her pointless to buy new furniture when might be gone tomorrow, so lived with ripped cushions (her Autistic son is hard on them) and when had new, now enjoys her home and even hired a maid to help her).
I don't understand what this means, by the way.
I believe so also.
You too! Hopefully talk soon, itching to get an amplifier built.
"...don't understand what this means...
It means there has been an argument going on for decades about how people hear, how we measure audio device performance, the assumptions we make in relation to the those two things, whether or not the assumptions are close enough, how humans form and maintain beliefs about such things, etc. Its can get complicated, as well as polarizing much like politics has become. The subject remains controversial. Way too much to get into much detail about here.
It means there has been an argument going on for decades about how people hear, how we measure audio device performance, the assumptions we make in relation to the those two things, whether or not the assumptions are close enough, how humans form and maintain beliefs about such things, etc. Its can get complicated, as well as polarizing much like politics has become. The subject remains controversial. Way too much to get into much detail about here.