[Chewbacca]

That's awesome you got the Studio's on order! I'm sure those things are going to be amazing if they're anything like the Oticas... which they are of course!

The one unit that (usually) always comes with a volume control would be the preamplifier. Think of that as your main hub to control everything - along with another link in the chain that adds amplification, but the one that can adjust it's output (volume control). Usually a DAC that has a volume control, is (generally) a bit of an afterthought, and they won't put as high of quality parts in that part of the device, because maybe only 25% of the people are going to utilize it - So a lot of the time they won't include a remote. Again, that MP-D2 is a great solution with it's built in "preamp"/volume stage - Although I haven't checked if it's an amplified stage? Or if it just takes away volume from the chain as more of a buffer stage? Maybe something to look into, or someone else may know a bit more, or I could look into it as well lol. Just didn't need to since I didn't plan on using it. Or that Holo Audio Spring DAC mkrawcz mentioned may be a great solution as a stop gap as well! I've only heard great things about those DACs.

Also - as far as amplification, I believe your thinking is probably backwards, as I know mine was before getting into this. So generally larger speakers are actually easier for an amplifier to drive to louder volumes than a smaller speaker. This is what speaker efficiency is. The industry standard of measuring this is throwing 1 watt of power at the speaker and see how loud it plays (more or less). With a smaller speaker like the NX-Studio (which idk what the efficiency is... let's say 87db?) @ 1 watt of power will play at 87db (again, this isn't an accurate measurement) and the Otica @ 1 watt of power will play at 93db. Wait... But doesn't it take more for the amp to power more physical drivers? (Studio having 2, Otica having 7) - it's physically moving more mass, so that would make sense. BUT, with the way speakers are wired, the woofers are all paralleled together, the two mid drivers are paralleled together as well. So the signal goes thru one of the drivers, goes right to the other driver, to the next, to the next, so they're all using the same signal (same power), and this is at the speed of light. So it happens so instantly fast that there is absolutely not time delay (that's perceivable to the listener) when the sound comes to you. Because it's going from the speed of light (electricity) to the speed of sound when the signal vibrates off the driver. Then realize the drivers themselves are so efficient that they themselves don't suck up a bunch of power leaving none for the next one in line. So you're getting nearly 4x the output with 4 drivers paralleled compared to 1 off the same signal - yet the amplifier is still just as happy to produce the same signal - yet much louder for the 4.

Let's clear some facts so you understand how we hear, and how an amplifier needs to work to attain this amount of SPL (sound pressure levels). For every 6db increment you physically hear things twice as loud. For every 3db increment your amplifier needs to output 2x the amount of power.

SO - what does this mean?? Let's compare the Studio with the Otica. AGAIN I do NOT know the efficiency of the Studio, and this is for illustration purposes only.

NX-Studio: 87db efficient @ 1 watt. 90db efficient @ 2 watts. 93 @ 4 watts. 96 @ 8 watts etc.

NX-Otica: 93db efficient @ 1 watt. 96db efficient @ 2 watts. 99 @ 4 watts. 102 @ 8 watts.

So basically the Otica's will produce twice the amount of SPL for the same signal being thrown at them. AKA they will SCREAM with low wattage amps... But going to the 1-5 watt amps, probably are out of it's realm of ideal.

There's ALOT more that goes into it than that though. That's a very basic understanding (at least how I understand it, compared to most here I'm quite the noob).

Use this link to basically figure out how loud a combination of speaker efficiency and wattage will give you for maximum SPL. This is right where the amp will clip, and you will get audible distortion or damage your speakers - So you do want some headroom!

http://www.hometheaterengineering.com/splcalculator.html

Hope this help! ALOT of knowledgeable people here to help you with any questions!

[nadirmg]

I'm lusting after this...... because NDR used it in his demo for the NX Oticas.





I don't need something that expensive. But mainly I'm drawn to what I know works with the NX Studios/NX Oticas.

[Chewbacca]

I'm sure that DAC is absolutely lights out, and I would hate to stop a potential sale from happening with a company. But one thing you need to realize is DACS are the without a doubt the most turned over item in any system - for the sole fact that it's really the only technology in speaker audio that is skyrocketing forward... everything else is kinda in turtle mode. We're still using vacuum tubes...

So, DACs generally will be very out of date in 5 years... The rest of the system? Besides for maintenance, those items should perform as good or better than anything that will be made in your lifetime. Of course unless some new fandangled tech comes out that totally blows things out of the water. Again.. We're using vacuum tubes. Even IN the DACs!! It's comical in a sense. What other type of technology still does that? It's just physics... so cool.. OKAY I digress.

So, do you want to spend $5k on something that will be worth $2.5k in 2 years, and $1000 in 10? This is for maybe 10% more performance than another model that may be $2k. But the newer $2k model that's coming out, in let's say a year, will be vastly better than your $5k unit already.... Can't say that with a speakers, amps, preamps, cables, turntables, etc...

My limit was always $1k on a DAC... I got so lucky on mine with a local sale of a fellow member here, I got mine for near that - Couldn't pass it up.

Something to ponder on!

[nadirmg]

That is really good info... I had no idea. It's like spending $5k on the new iphone when a new one comes out every year hmm?

And thank you for all the info on the sound efficiency with amps. I'm going to get on the phone with Danny next week and ask him about the NX Studios. I want to do this right and not damage my speakers at higher volumes.

I've got more homework!

[cjsailer]

If you are looking at a Holo May, you could also look down the Holo product stack at the Holo May 3, which has near the same level of performance and you can also add-on a pre-amp module for volume control.  Also, another "reasonably" priced R2R ladder DAC manufacture would be Denafrips with the Aries II, Pontus, Venus, Terminator models.  I don't think the R2R DAC topology will be obsolete as quickly as chewy suggests.  The R2R topology isn't as susceptible to obsolescence as delta-sigma based DACs, because the chips are not the cornerstone of the R2R design, it's the resistors.  If an R2R DAC sounds great now, it's still going to sound great five years from now.  Where technology is concerned, you're always buying something that has its replacement right around the corner.  You don't want to be an old man waiting for technology to stop advancing before smashing the buy button.  In the end it comes down to what you want.  If you like keeping up with the new sound formats, then a mid-tier DAC strategy, being replaced every couple of years would work.  If you are a PCM guy and already have an established music library, I don't think you can go wrong with a high end R2R DAC.

[Hobbsmeerkat]

I got to borrow a Kitsune tuned Holo Spring II DAC for a few months and it was absolutely fantastic, especially paired with tube gear.
It knocks the socks off my $200 Grace DAC/amp in both clarity, sounstage and imaging.
But I haven't had much chance to listen to the May DAC yet, but I've only heard glowing things about it.
Same goes for Denafrips DACs.

[nadirmg]

Any suggestions from used gear buying veterans?

I found an upgraded pair of Odyssey Stratos mono amps that are about 50% of retail cost. Could be good...

Is it a complete gamble to buy used gear the way it would be buying a used car off of Craigslist, or is it pretty safe?

And I don't know if the "buckling" on the top of the chassis housing (it does it on both amps) is an indication of damage or not. Any thoughts? I've got a message to the seller asking them about it.



It's a good thing I'm single and live by myself. I can use my money and my house however I want.. which might be harder if I had a lady with her own ideas.

[nadirmg]

If you are a PCM guy and already have an established music library, I don't think you can go wrong with a high end R2R DAC.

Yeah, and it's not like the sound quality gets worse for this tech when the new things come out (unlike the speeds of computers that are designed to get slower with operating system updates.

btw, what is 'PCM'? PC Mac?

[Chewbacca]

@cjsailer - I’m sure you’re correct in the fact the R2R tech won’t be gone in 5 or 10 years, but I would imagine a 5 year old R2R DAC and 5 year old delta sigma would still sound different in performance, than one now. Otherwise no one would have bought any new R2R dacs in recent years if their advancement ceiling has been reached. Regardless of technology used, I think anything that’s changing a digital signal to analog still hasn’t reached its peak - if you compare it to other pieces in the chain.

I just do believe it’s the “iPhone” of the music chain. Yeah, the first iPhone is still great. But, would you want it knowing what else is out? Probably not. A tube amp from year 2007? I wouldn’t think twice.

Just my .02!

Also Denafrips makes amazing products. I almost got two of them off the used market but was too late to the posts, then found the MP.

[Chewbacca]

Those Odysseys could be a great deal! Those are also Khartagos btw, and not Stratos. But I’ve mentioned here before, that Odyssey amps are not at all judged by performance of the case they use. You can have an all out balls to the wall 100% maxed out Kismet amp in Khartago cases.

So you’d want to see a picture of what’s inside the amp. Ideally you’ll want a black board, light blue caps (kismet standard) or off board white caps (they’re huge, the Kismet hyper caps) and an newer style transformer. This of course isn’t necessary, just more in line with the performance of the NX series.

As far as the case being pushed up like that, it’s a little strange. I know mine is tight with the 4-pack of board caps to the bottom of the top cover. But it doesn’t bulge it up like that. I’d definitely inquire about it!

As far as reliability goes, Klaus (the man behind the company… just amazing to deal with btw) has a 20 year warranty on all his products. He highly supports his used market as well!

[JackD]

Their are a three year old used pair on US Audiomart for $2000 that are a safer bet. They are in Milwaukee

[nadirmg]

Those Odysseys could be a great deal! Those are also Khartagos btw, and not Stratos. But I’ve mentioned here before, that Odyssey amps are not at all judged by performance of the case they use. You can have an all out balls to the wall 100% maxed out Kismet amp in Khartago cases.

So you’d want to see a picture of what’s inside the amp. Ideally you’ll want a black board, light blue caps (kismet standard) or off board white caps (they’re huge, the Kismet hyper caps) and an newer style transformer. This of course isn’t necessary, just more in line with the performance of the NX series.

You're right they are Khartago cases. And here's a pic of the inside, which I have no idea what I'm looking at but it looks like dark blue caps and a red board.

[nadirmg]

Their are a three year old used pair on US Audiomart for $2000 that are a safer bet. They are in Milwaukee

Awesome - I'll check 'em out! What makes you think they're safer? The fact they housing is in better shape?

[mlundy57]

Yeah, and it's not like the sound quality gets worse for this tech when the new things come out (unlike the speeds of computers that are designed to get slower with operating system updates.

btw, what is 'PCM'? PC Mac?

There are two main ways of recording and storing music, PCM (Pulse Code Modulation) and DSD (which is technically PDM, Pulse Density Modulation). The majority of music is in PCM, think CD, and is listed as bit depth and sampling frequency (44.1kHz/16 bit, 48/16, 44.2/24, 48/24, 88.4/24, 96/24, etc.). For DSD think SACD. It is always recorded at 1 bit so only the sampling frequency is listed as multiples of the CD quality PCM frequency of 44kHz. Single rate DSD has a sampling frequency of 64 times CD quality and is referred to as single rate DSD or DSD 64. Double rate is twice that or 128 times CD quality (DSD 128). Quad rate DSD is double that or 256 times CD quality (DSD256).

All DACs can play PCM. Many others can also play DSD using a workaround called DOP which stands for DSD over PCM. Others can also play DSD natively at least at single rate. IIRC, DOP is a work around needed for PC based music servers like mine. I don't think Macs have the same issues with DSD playback  PCs do.

Your music playback software also has a role to play. I'm familiar with JRiver and ROON. In JRiver you can configure the playback to any format your DAC can handle. Years ago I had a Schiit Audio DSD DAC. This DAC could only receive single rate DSD so I configured JRiver to output all music files as DSD64 no matter what format the file was stored in. I current use ROON which talks to the DAC and, if the file type is not one the connected DAC can handle, automatically outputs the file at the highest rate the DAC can handle. For me ROON is the easiest since I stream music from the one server to three different locations in my home each with a different DAC with different capabilities. Roon can handle each DAC individually even when music is playing in all three locations at the same time.

Your assumption that whatever DAC you buy today will sound just as good 10 years from now is accurate. It's abilities will not deteriorate. Chewy is also correct that DAC capabilities improve rapidly so for the amount of money you spend on a DAC today, in 3-5 years you can get a better sounding DAC for the same or less. Again, that doesn't mean the DAC you buy today will sound worse down the road, just that newer technology will sound better.

It comes down to a philosophy on the order of importance of the parts of the system. Ask 10 people and you will likely get 10 different answers. In my opinion, speakers are the most important followed by proper set-up of the speakers. Then room treatment to correct any issues set-up can't handle. Next for me is the source. For digital music this means the DAC, server, and/or streamer in that order. For vinyl it means the phono preamp, cartridge, and turntable in that order. Then the power amp and preamp, in that order for separates. Cabling should be properly designed for the application and well made but doesn't need to be crazy expensive or out of proportion to the components. In other words, don't spend $1,500 on cabling for a $500 component. Rather, spend $1,500 on a better component and $500 on cabling. You get the idea.

[nadirmg]

Their are a three year old used pair on US Audiomart for $2000 that are a safer bet. They are in Milwaukee

ooooh i see now. They are Kismits in the Khartago chasis. And they seem to be in better shape too!
Nice find!

[cjsailer]

Chewy, your advice on the DAC was 95% correct. Sorry I may have come off as dismissive, but I just wanted the OP to understand that R2R DACs do not go obsolete as quickly as the Delta sigma ones.  As mlundy said earlier, analysis paralysis is real and if you layer in value proposition into the equation, it becomes very hard to pull the trigger.  I myself have been been in this limbo with my next DAC, can't decide between two options. ... and for what maybe 5% performance in the audio chain?

nadirmg, where I was going with the PCM comment was, if you don't care about what the latest and greatest music format is, then whatever DAC you decide to go with should be good for years to come and you can go for a high quality one now.  If you are into streaming and want to try out the new music formats, then the strategy chewy puts out there is correct.

[nadirmg]

So both sellers got back to me about their Odyssey amps

The one with the slightly bulging frame was originally a Khartago and upgraded by Klaus in 2020. Here's what the seller said about the upgrades (it eases my mind greatly):

"After discussing options with Klaus, we agreed that he would upgrade the caps, transformer, and wiring (Groneberg reference cable) as well as adding extra caps, and an additional upgraded input. They are now somewhere between 180-200 watts per channel with current to spare for any speaker out there. Additionally, I have since purchased Klaus’s Candela tube preamp and it’s a match made in heaven! They have great punch and never broke a sweat with my Vandersteen’s. The lager transformer  is exactly why the case bulges in the rear. He added a pad inside the case for protection."

Its stats are:
1 x 180 Watts RMS @ 8 Ohms (each)
2 Ohm load stable
Class A/AB
1 – 600,000 Hz frequency range
120,000µF memory (each)
120 amps current delivery
< 0.04% THD (not audible)
> 800 continuous damping factor
Input impedance 22K ohms
DC offset > 1 mV
RCA & XLR (bridged) inputs
400 VA Plitron transformer (each)
Sanken Epitaxial Planar Transistors 2SA1216 & 2SC2922
Anti vibration dual thickness PCB
Power consumption when idle ±30Watts
4 internal fuses 250V/6.3A, 5x20mm, fast blow

I understand this first seller has made upgrades but I'm not sure how they compare against the mono amps below:

The other set I'm looking at is a Kismit plus extreme in Khartago chassis. He is the original owner. He's also made some upgrades. Stats below:

"For sale are a pair of Odyssey Kismit Mono plus Extreme mono block amplifiers in the Khartago chassis’.
Which include:
WBT binding posts
Symphonic Line 120,000uF caps
Upgraded to 800VA Plitron Transformers
Vishay/Dale resistors
Extra WIMA metal film capacitors
Snakebite Epitaxial Planar transistors
Anti vibration dual thickness PCB’s
Xlr/Rca inputs
200W @ 8 Ohms
Class A/AB
120 amps current delivery
>800 continuous damping factor
Input impedance 22km Ohms
I am the original owner purchased about 3 years ago from Odyssey Audio."

What do you guys think? If I had a few years experience with this stuff, I'm sure I could tell the difference... Which set is better? The money is not the issue, but as long as I'm spending close to $2k, I'd like to go with the amps that have the higher specs.

Also, how do you guys trust that you're not getting ripped off by sellers?
Thanks guys, I'm soooo excited to learn all this stuff. I can see this quickly become a favorite hobby.

[JackD]

Second set you listed and Klaus can verify the upgrades by phone if you give him the serial numbers.

[Jonathon Janusz]

The first one looks like a (well) upgraded Khartago, but the second set in Milwaukee look a lot more like top-end Kismets in Khartago chassis.

I'm in Wisconsin and have been using a Khartago with a pair of either X-LS or X-SLS for years which I enjoy.  If I were in the market to move up the Odyssey line, I would be very tempted to drive to Milwaukee to pick up that pair of amps!   They look like a very, very good deal.

[NoahH]

I am glad.the DAC longevity conversation came up as it has made me revisit this. I don't actually think the obsolescence stuff is very real there any more.

The place I see a ton of evolution right now is music servers and streamers. Those are changing fast, but DACs have not. Denafrioa Terminator vs Terminator 2 are nearly the same, mostly a little improvement in layout and in parts. The Holo stuff is a new maker altogether, and the reasons for the quality seem to all be design and parts, not technology. The async USB tech change was big, but that was a long time ago now. We might have a USB-C change at some.point, but an adapter will solve that. It simply seems like DACs have stabilized as a technology.

Again, servers and streamers are still wild west. Class D amplification is the other place that seems to be getting the most innovation. DSP is up there too - active speakers are also moving fast, often times as they are at the intersection of several of those other technologies.