[Paladin79]

I have just started coming up with a bom for a passive rca switch box. I have a question about the type of switch. Pretty basic switcher 4 in 1 out, I was planning on building two of them to give me a 4x4 matrix possibility. For the switch I was leaning towards 3p-4t-1d with the idea that each input/output would consist of r/l hot and common bonded ground. I have seen some designs that just star ground all of the inputs/outputs and use a 2 pole switch. Any opinions on this?

I prefer running grounds at the inputs and outputs. I had a switch laying around that I bought years ago. I will see if I can find the info, I must have had it for ten years lol.

 

[Paladin79]

I’m interested! Love to hear about dac comparisons!

I sent the info, this comparison was relatively simple. Jason at Schiit just wrote a chapter about different classes of amplifiers and I may be working on blind comparisons between between class A, AB, and D amplifiers. I also thought it would be cool to see how many could tell the difference between tube and solid state, a more likely event. I had worked with Jason on a 6sn7 comparison years ago and he may try to replicate the amp challenge as well if I can bring it about. We even compared boutique fuses and more standard fuses at one point just for laughs.

 

[L0rdGwyn]

I have just started coming up with a bom for a passive rca switch box. I have a question about the type of switch. Pretty basic switcher 4 in 1 out, I was planning on building two of them to give me a 4x4 matrix possibility. For the switch I was leaning towards 3p-4t-1d with the idea that each input/output would consist of r/l hot and common bonded ground. I have seen some designs that just star ground all of the inputs/outputs and use a 2 pole switch. Any opinions on this?

You don't need to switch the grounds, you can connect them all together and just switch the hots. For this you'd want a two poles (right and left) and four throws, single deck. Connect your outputs to the common of each pole, inputs to the four throw positions. Connect all the input grounds together and ground to chassis, connect the output grounds to chassis.

 

[oppman99]

Earlier this month friends and I completed a DAC comparison, rating 16 DACS that sold below $7,000 each. It may or may not interest any of you but it helped me narrow my choices down to five DACS I will listen to on my home system so I can choose my final DAC. I have all other gear in place for my dream system, it may not be the most expensive or most well known but it is what I enjoy. Amps, speakers, headphones, CD transport, and turntable are all in place and now I know the top five DACS 46 people chose, they were my choices as well, so the final listen begins.

I would be interested in this also.

 

[L0rdGwyn]

I'm going to borrow Zach's Susvara for a bit when @heliosphann is that with it. We'll see what all the hype is about! It will also help inform future designs based on how much power they really need.

 

[Monsterzero]

I thought the Aegis drove the Susvara quite well. Quite spacious sounding and good bass, but I prefer solid state for planars, at least when using a tube based DAC.

 

[goldwerger]

I'm going to borrow Zach's Susvara for a bit when @heliosphann is that with it. We'll see what all the hype is about! It will also help inform future designs based on how much power they really need.

With the Susvara, I find it's no so much how much power they need as much as how much power they benefit from.. (easy to listen and be wowed, until you try an even better amp). That one is a goose chase if I've ever seen one..

I rotate my Susvara between the Moon 330A (power amp), CFA-3, and Auris Nirvana; and every time I think I decided which is the best, I change my mind.

In my setup, the transformer coupled Nirvana adds a bit more bass texture and weight, while the CFA-3 opens the upper frequencies and widens stage (the Moon probably provides the best of both).

I do think the Susvara benefits a lot from beefing up the bass texture, so if you managed to capture that with the Aegis without any tradeoffs in the puper FR it would be awesome!

 

[Monsterzero]

(easy to listen and be wowed, until you try an even better amp). That one is a goose chase if I've ever seen one..

I was very much 'wow'd' by Sus, but ultimately I found it to be quite fatiguing to listen to for much more than an hour. I kept turning the volume down....and down until my preamp was sitting at -35, whereas I like to keep it around -13. I just kept getting a headache each and everytime, and then I'd switch to the Caldera, and boom, no more headache.
Whether that was due to the amps I was using or not, I have no idea, but I no longer have an itch to own a pair, and whichever amp I get next, it's ability or otherwise to drive the Susvara will not be a concern, but I get why some love it.

 

[goldwerger]

I was very much 'wow'd' by Sus, but ultimately I found it to be quite fatiguing to listen to for much more than an hour. I kept turning the volume down....and down until my preamp was sitting at -35, whereas I like to keep it around -13. I just kept getting a headache each and everytime, and then I'd switch to the Caldera, and boom, no more headache.
Whether that was due to the amps I was using or not, I have no idea, but I no longer have an itch to own a pair, and whichever amp I get next, it's ability or otherwise to drive the Susvara will not be a concern, but I get why some love it.

As you know, I love my Caldera as much as the Susvara (a massive achievement for Zach, those are just wonderful and a remarkable achievment). But I never had fatigue with the Sus. I do think a TC amp may prove much easier with it as as it warms it up just a touch (at least on my chain); I think the higher frequencies get some people, and SS tend to expose them more on the Sus for me. I know the Aegis is in your future, so.. perhaps round 2 some time.. ?

btw, I'm still not building an amp tomorrow morning, but I have a lot of down time this month as I dawdle around the house with my arm in a sling, so I started reading more seriously about tube amp circuitry.. the distance for me between zero and madness has often been a little nudge.. who knows...

 

[Monsterzero]

As you know, I love my Caldera as much as the Susvara (a massive achievement for Zach, those are just wonderful and a remarkable achievment). But I never had fatigue with the Sus. I do think a TC amp may prove much easier with it as as it warms it up just a touch (at least on my chain); I think the higher frequencies get some people, and SS tend to expose them more on the Sus for me. I know the Aegis is in your future, so.. perhaps round 2 some time.. ?

btw, I'm still not building an amp tomorrow morning, but I have a lot of down time this month as I dawdle around the house with my arm in a sling, so I started reading moreseriously about tube amp circuitry.. the distance for me between zero and madness has often been a little nudge.. who knows...

I'm actually skipping the Aegis. not because it's not a killer amp (cuz it is) but I just can't hang with tracking down and paying for the best tubes for it. In my system is was quite mid forward and it took me awhile to reign the mids in some, using the tubes Keenan included in the tour, all of which were god tier tubes.

I'm just about finished with hunting down the tubes I'm missing for the Airmid, and fairly close with tube chasing for the TRP as well. The thought of starting all over for the Aegis makes my stomach churn. One end game SS amp and I'll call it a day.
Def build one though. I like it a bit better than the Airmid, which is a killer amp as you already know. Lots of the same characteristics.

Re: Susvara...I did not find it bright and certainly not sibilant in the least. Where the fatigue was coming from I have no clue. I'm chalking it up to sensory overload, but your guess is as good as mine.

Now perhaps if I can convince @CEE TEE to build me a crazy solid state amp based upon the Ravenswood with multiple HP jacks I'll be set!

 

[goldwerger]

I'm actually skipping the Aegis. not because it's not a killer amp (cuz it is) but I just can't hang with tracking down and paying for the best tubes for it. In my system is was quite mid forward and it took me awhile to reign the mids in some, using the tubes Keenan included in the tour, all of which were god tier tubes.

I'm just about finished with hunting down the tubes I'm missing for the Airmid, and fairly close with tube chasing for the TRP as well. The thought of starting all over for the Aegis makes my stomach churn. One end game SS amp and I'll call it a day.
Def build one though. I like it a bit better than the Airmid, which is a killer amp as you already know. Lots of the same characteristics.

Re: Susvara...I did not find it bright and certainly not sibilant in the least. Where the fatigue was coming from I have no clue. I'm chalking it up to sensory overload, but your guess is as good as mine.

Now perhaps if I can convince @CEE TEE to build me a crazy solid state amp based upon the Ravenswood with multiple HP jacks I'll be set!

yea, every tube amp opens a whole fresh can of worms of hunting and optimizing..

 

[L0rdGwyn]

With the Susvara, I find it's no so much how much power they need as much as how much power they benefit from.. (easy to listen and be wowed, until you try an even better amp). That one is a goose chase if I've ever seen one..

I rotate my Susvara between the Moon 330A (power amp), CFA-3, and Auris Nirvana; and every time I think I decided which is the best, I change my mind.

In my setup, the transformer coupled Nirvana adds a bit more bass texture and weight, while the CFA-3 opens the upper frequencies and widens stage (the Moon probably provides the best of both).

I do think the Susvara benefits a lot from beefing up the bass texture, so if you managed to capture that with the Aegis without any tradeoffs in the puper FR it would be awesome!

Good to know. I don't have a solid state amp around, so tubes it will have to be more than high power this headphone needs is an amplifier with a reasonably low output impedance, not all that common with tube amps.

I'm actually skipping the Aegis. not because it's not a killer amp (cuz it is) but I just can't hang with tracking down and paying for the best tubes for it. In my system is was quite mid forward and it took me awhile to reign the mids in some, using the tubes Keenan included in the tour, all of which were god tier tubes.

I'm just about finished with hunting down the tubes I'm missing for the Airmid, and fairly close with tube chasing for the TRP as well. The thought of starting all over for the Aegis makes my stomach churn. One end game SS amp and I'll call it a day.
Def build one though. I like it a bit better than the Airmid, which is a killer amp as you already know. Lots of the same characteristics.

Re: Susvara...I did not find it bright and certainly not sibilant in the least. Where the fatigue was coming from I have no clue. I'm chalking it up to sensory overload, but your guess is as good as mine.

Now perhaps if I can convince @CEE TEE to build me a crazy solid state amp based upon the Ravenswood with multiple HP jacks I'll be set!

Probably when I am done optimizing both my headphone and two-channel systems, I'll start designing some solid state circuits. Things I have left to do are finishing my PCM63 DAC (which will be done in the next two weeks), build my LCR phono stage (LCR chokes are ordered, tubes acquired, and high level design is done), and my end-game transformer coupled headphone amp (transformers ordered, tubes acquired, design done). It's possible I'll have all that done by the end of the year. I'm interested in doing a VFET/SIT design first, which are all the rave over on diyAudio. These transistors have characteristics very similar to tubes, they are no longer in production, but I bought a few pairs a while back for when I am ready to build with them. I have a design done for a 50W single-ended power amplifier, I need to come up with something more scaled down for headphones...

 

[Paladin79]

yea, every tube amp opens a whole fresh can of worms of hunting and optimizing..

I generally start with headphones and speakers and work my way back. I then design a tube amp to go with those transducers. The exception for me was hearing a specific pair of Sonus Faber speakers with a PrimaLuna amp, I loved the combination so I bought that set. I will do the same with a DAC, I am going to listen to my favorite five with my other gear before selecting one that goes with that combo (I already know how they sound with my headphone amp and and headphones.)

Oh and Focal Utopias are my favorite headphones with my amps. I have tried most anything else made at one time or the other.

 

[goldwerger]

I generally start with headphones and speakers and work my way back. I then design a tube amp to go with those transducers. The exception for me was hearing a specific pair of Sonus Faber speakers with a PrimaLuna amp, I loved the combination so I bought that set. I will do the same with a DAC, I am going to listen to my favorite five with my other gear before selecting one that goes with that combo (I already know how they sound with my headphone amp and and headphones.)

I always start with the headphone (always have way too many of those) and then look for the amp synergy. But the finer tuning of tube selection (and hunting them down) gets extreme at times. So I get ‘monsterzero’ reluctance to lift another curtain…

 

[Paladin79]

I always start with the headphone (band always have way too many of those) and then look for the amp synergy. But the finer tuning of tube selection (and hunting them down) gets extreme at times. So I get ‘monsterzero’ reluctance to lift another curtain…

The main driver tubes I use are 6SN7’s and my local group and I did a study on those and they’re equivalents and rated right at 1500 6SN7’s. Luckily we did this a couple years back when some tubes were easier to buy. We also worked with a lot of 6080, 6AS7, 5998, etc.

I do not know all tubes, but some I know extremely well.

Oh and four of my tube amps were used for testing so I know my test scores as well as those of 50 other participants. We use those amps to this day.