The DIY'rs Cookbook

[atomicbob]

 
Thank you AB,
 
So, it's ripple that we're talking about, 
 
I hadn't thought of or considered any of the "advantages" you mention, I'd considered "Tube Rolling" as the only advantage.  
 
Now, I understand that Power Supply rolling, OP-amp rolling and a few other things that can be changed or adjusted are the main Feature sets.
 
Garage1217 are a Neurotic/Psychotic's "Dream" design, the Schiit Vahalla 2 would be the other side of this Coin. ( along with the Bottlehead that I liked so much )
 
All of us reading this Head-Fi are DIYers, some work with a soldering iron, most work with a Credit Card, we are on a fun Adventure.
 
Thank you for offering reliable advice on these matters.
 
Tony in Michigan

Hi Tony,
 
Ripple was the particular attribute for which I chose to provide graphs. It isn't the only one that improves. There are also load regulation, residual regulation perturbations and oscillations, very high frequency noise (spikes), and so on. I chose not to post the additional graphs so I wouldn't feel obligated to explain how to read those graphs to anyone not familiar with the measurements. I'm not retired yet and still must live within time constraints for my discretionary free time.

 

[atomicbob]

   
Hi atomicbob,
 
The one component that sometimes gets left out of the discussion around implementing linear power supplies is the cable used between the linear power supply whatever it is powering.
 
Do you usually build these by hand?  Or are they available for purchase anywhere (from the linear power supply vendor or third parties)?
 
It seems to me that this might be useful information, particularly for those of us who might not be comfortable with building a custom cable (particularly if wiring it incorrectly might put the equipment we want to power at risk).  And looking at the various things around the house that are powered via wall warts, there can be a not insignificant amount of variance on the kinds of connectors used, polarity, etc...
 
Any insights you have on this would be much appreciated, time permitting of course.
 
Thanks!
 
--Nedifer

A very good question. I built my own using Cable Matters OFC 14 gauge twisted pair and 5.5mm x 2.1mm CCTV power plugs and Pomona MDP dual banana plug in the case of the U8001A lab supply. Nothing magic, just short, highest gauge cable the connectors would accommodate. No soldering required with these particular plugs. The picture shows 16 ga but I have since replaced with 14 ga.

 

[atomicbob]

  <edit>
I do kinda like Tubes.   I started life when 80 & 75 Tubes were in common use, but I've gone Solid-State, decades ago, when I discovered how well they deliver deep bass.  I'm a Schiit Asgard2 owner and a previous Agent of Electrocompaniet.  
 

Garage1217 amps, though they have a tube in the path, delivery nearly DC thanks to their topologies. That said, the Asgard2 is a very nice amp with a substantial linear power supply built in. I am evaluating one of those as I write this. Asgard2, Bifrost MB, HD650 and Sonarworks Ref3 compensation played through JRiver MC. I still have a slight preference for the Project Sunrise III (12BH7) and LPS. But I would listen to the Asgard without hesitation, and probably will do so all evening (and more.) I could be listening with the Ygg or GiMB and Liquid Crimson, Liquid Carbon or ZDSE and HD800 or any of a dozen other lab cans.

 

[tonykaz]

Dear AB,
 
Thank you for this explanation.  I probably realized these performance features of Power Supplies, I once bought an Instrument Grade Power Supply for our Experimental Lab that already owned a few such devices.  
 
I only summarized by saying "ripple", of course much more is involved in the performance of these devices.  
 
I'm not at all certain that I wish to go beyond "playing" with tube rolling.  I'm quite pleased with my gear, little packages arriving in the Mail would or could be another bit of excitement.  Geez, I could buy these things from all over the World. What fun.  Trying a wide range of Tubes is the attraction for me.  I suppose I could buy another Lab Power Supply ( they aren't all that expensive ) but I'm not certain I want a bench with a Scope and other gear, I am having a great time with my Festool stuff and building little projects.   I'm also building a collection of "The Great Courses" on CD.  I have time to learn stuff that I've never had access to!
 
Thanks (too) for the "slight" preference comment, it kinda falls into line with my own experience with Amps.  The only Blown-Away amp experiences I've had were from the Conrad-Johnson MV-45a driving Magnapans  and the Electocompaniet Ampliwire Amps playing Dynamic Speakers. My little Schiit performs equally with the Electrocomaniet ( I may own an especially good Asgard2, I don't hear of others raving about the design ), right now I'm listening to Colin Davis/Boston Sym. playing Sibelius Sym #3 which is sending shivers down my back, the ultra low frequencies are taking me to quivering ( Senn. HD580s ) Phew!!  
 
Anyway, thanks for writing.
 
Tony in Michigan 

 

[atomicbob]

So at the end of the day, if you want to roll tubes (12BH7 is a must try), change output impedances, try different power supplies and generally experiment, the Project Sunrise III is a great approach for the amp. If you don't want to change anything and really want everything to be free of such experimentation while achieving a really good sound, then Asgard2 is great choice. Either with a Bifrost MB of course. And HD650 or HD800 headphones.

 

[landroni]

  So at the end of the day, if you want to roll tubes (12BH7 is a must try), change output impedances, try different power supplies and generally experiment, the Project Sunrise III is a great approach for the amp. If you don't want to change anything and really want everything to be free of such experimentation while achieving a really good sound, then Asgard2 is great choice. Either with a Bifrost MB of course. And HD650 or HD800 headphones.

Would PSIII or Asgard2 be capable of running (and performing well with) something really inefficient like the HE-6?
 
It comes with the following specs:
http://hifiman.com/products/detail/75
Sensitivity : 83.5dB
Impedance : 50 Ohms
 
Asgard2 does:
Maximum Power, 32 ohms: 1.0W RMS per channel
Maximum Power, 50 ohms: 1.0W RMS per channel
 
And PSIII can do something like 0.5W per channel into 64 ohms.
 
My understanding is that the HE-6 needs something like at least 1W per channel for full blast, and their recommended amps come with 2W per channel. But I'm new to this kind of computations and may be getting it wrong...

 

[bimmer100]

Would PSIII or Asgard2 be capable of running (and performing well with) something really inefficient like the HE-6?

It comes with the following specs:
http://hifiman.com/products/detail/75
Sensitivity : 83.5dB

Impedance : 50 Ohms

 
Asgard2 does:
Maximum Power, 32 ohms: 1.0W RMS per channel

Maximum Power, 50 ohms: 1.0W RMS per channel

 
And PSIII can do something like 0.5W per channel into 64 ohms.

My understanding is that the HE-6 needs something like at least 1W per channel for full blast, and their recommended amps come with 2W per channel. But I'm new to this kind of computations and may be getting it wrong...

From what I understand, there are not a lot of amps that can power the he-6 properly. And by proper, I mean well and ideal. I would estimate that the PSIII and Asgard2 couldn't power them well at all. Basically will sound like tin cans and low DB. The ragnarok can power them if you like schiit amps, and I know the he-6's sound sublime from my audio-gd master-11 with more than enough power to drive them properly.

It does 8000mw per channel @50ohm and pure class A.

I have not tested the he-6 on an asgard2, but looking at the specs I would say it wouldn't drive them well. And surely not the project sunrise III. Please correct me if I'm wrong since I don't own that gear, but am saying this just based on white paper specs. I believe those amps were recommended with specific headphones in mind. Nothing like the HE-6! Which happens to be the hardest to drive headphones around. But if you're on a budget, the asgard2 and a pair of hd650's will be hard to beat. Not to my liking, but they are good amps for the money.

I think the 86db @50ohm is with 1000mw per channel, so if 86db is enough... Ok. Maybe why they recommend at least 2watt per channel, but that still doesn't get to "blasting" levels. I don't recall the exact math for power increase=however many more DB. please chime in if you can give some estimates of what the he-6 would require for "blasting" levels. I would say 92-95db is more than enough for most listeners who like to blow their ear drums the downside would be when you have low level recordings and require even more power to drive them to ideal DB levels. That's why I ended up buying a beast of an amp. I love classical music and love to listen at higher DB than some. Even my he560's I think are hard to drive for most amps. But what do I know, I have only tried them on a couple dozen amps with a handful of the amps being able to drive them well in all conditions and have a tiny bit of headroom.

 

[atomicbob]

 
Would PSIII or Asgard2 be capable of running (and performing well with) something really inefficient like the HE-6?
 
It comes with the following specs:
http://hifiman.com/products/detail/75
Sensitivity : 83.5dB
Impedance : 50 Ohms
 
Asgard2 does:
Maximum Power, 32 ohms: 1.0W RMS per channel
Maximum Power, 50 ohms: 1.0W RMS per channel
 
And PSIII can do something like 0.5W per channel into 64 ohms.
 
My understanding is that the HE-6 needs something like at least 1W per channel for full blast, and their recommended amps come with 2W per channel. But I'm new to this kind of computations and may be getting it wrong...

The issue I have with using power to decide suitability of matching amp to electro-acoustic driver is that it doesn't sufficiently describe the necessary parameters. One driver may require high voltage and low current to perform optimally. Another may want the opposite, low voltage and high current. Yet both might have the same power required. I will attach a graph in another post demonstrating the needs of various popular headphones. Using the published nominal impedance and sensitivity for the HE-6 would require 50 mW to achieve 100 dB SPL average with 500 mW for 110 dB SPL peaks, assuming a 10 dB crest factor in the recording. But what the HE-6 really wants is 14Vpp with 100mA peak to hit the 110 dB SPL without strain.
 
<edit> I forgot to answer the question. I think the PSIII would be marginal at best for the HE-6 unless one listens at lower sound levels. My experience at meets is most listening to planars also listen VERY LOUD. Thus the discrepancy in adequacy of a given amp for a given listener. I probably could use the PSIII for an HE-6. I listen at 75 ~ 85 dB SPL in a quiet environment. Most others would find the PSIII inadequate and even the Asgard2 inadequate to achieve 110 dB SPL avg with peaks to 120 dB that I observe them listening. I built a SPL meter dummy head to quickly verify where listeners set their auditioning sound levels in my acoustic lab. It is based on the work of Joop Nijenhuis Headphone sound level meter.

 

[atomicbob]

20151228 update: this table contains some inaccuracies from old product literature. An updated version of this table including independent measurements appears here: http://www.head-fi.org/t/781268/the-diyrs-cookbook/195#post_12202114
 
Here is a table comparing the Vrms, Vpp, Ima and Power to achieve 100 dB SPL average and 110 dB SPL peak for various popular headphone, based on published specifications and nominal impedances. This ignores any impedance bumps a given headphone driver may have.

 

[bimmer100]

The issue I have with using power to decide suitability of matching amp to electro-acoustic driver is that it doesn't sufficiently describe the necessary parameters. One driver may require high voltage and low current to perform optimally. Another may want the opposite, low voltage and high current. Yet both might have the same power required. I will attach a graph in another post demonstrating the needs of various popular headphones. Using the published nominal impedance and sensitivity for the HE-6 would require 50 mW to achieve 100 dB SPL average with 500 mW for 110 dB SPL peaks, assuming a 10 dB crest factor in the recording. But what the HE-6 really wants is 14Vpp with 100mA peak to hit the 110 dB SPL without strain.

So he was asking if the Asgard 2 and the project sunrise III would be able to power the HE-6?
Do they have enough voltage? As your charts are informative, they also are confusing if you don't understand them entirely. I'm not too proud to admit I don't fully understand. so is there a simple way to look at things so things can give understood more clearly? I've not heard of anyone talking about powering their he-6 with 50mw or 100mw and 14vpp volts. And I mean explaining in those terms, not saying those specs would not be proper.
Can you explain the Asgard 2's specs with voltage vpp and vrms. Why is it that manufacturers don't explain these things?

Isn't there amps that will power every headphone well no matter what it wants? Would that be ideal? Or would my amp actually be crap for certain amps because it has too much power. When you said "One driver may require high voltage and low current to perform optimally. Another may want the opposite, low voltage and high current. Yet both might have the same power required." I thought to myself, well what do we look for to be able to tell if the amp will be ideal for the headphone. Is my amp not ideal since it may have too much power and not enough voltage, power or current etc. It sounds like too much power could be bad but I thought the headphone only will draw as much as it needs? Assuming it's available.

Why would a creative sound blaster e5 amp rated with 1000mw output not be enough to power some he-560's well. Sounds like crap in my opinion. And a geek pulse infinity can power the he-560's but with no headroom. Why do people say that amp is so powerful yet powers the he-560's to levels that are good yet at full maxed out volume and no headroom. I'm not complaining about the sound quality from a geek pulse infinity but I'm surely glad I didn't buy one since it has no headroom for classical music with low level recordings while using my he-560's. My nfb-28 did much better imho. I wish I understood more about amplifiers and why some do so much better than others.

 

[landroni]

I wish I understood more about amplifiers and why some do so much better than others.

Here are two pieces that go into the nitty gritty of amp specs and compatibility with headphones:
http://nwavguy.blogspot.ca/2011/09/more-power.html
http://www.rayfes.com/caraudio/ampspec.php
 
Both readings are quite terse and technical, but are very interesting if you want to better understand specs, what they mean and how they can be useful (e.g. matching headphones and amps). The first link gives a number of computations, but there is the occasional typo which doesn't help understanding, and some computations are a tad confusing. They do discuss at length Vrms, Vpp, mW, and how to convert between the various measures.

 

[atomicbob]

So he was asking if the Asgard 2 and the project sunrise III would be able to power the HE-6?Can you explain the Asgard 2's specs with voltage vpp and vrms.

Why is it that manufacturers don't explain these things?

Isn't there amps that will power every headphone well no matter what it wants? Would that be ideal? Or would my amp actually be crap for certain amps because it has too much power. 

Why would a creative sound blaster e5 amp rated with 1000mw output not be enough to power some he-560's well. Sounds like crap in my opinion.

Reasonable question. I did forget to answer the question and edited that post to offer a bit more opinion on the question. Still not a full answer. Without knowing how loud in SPL the user wishes to listen, it is hard to answer. I will have to measure the Asgard 2. On my (rather long) list of things to do in my spare time.
 
Garage1217 does sort of publish the information if one looks at their power graphs, though you have to work backwards from the power at a given nominal impedance to find the Vrms and I (current.) The math is fairly simple and only uses:
 
1)  I=E/R (where E is Vrms in this case) Ohm's Law
2)  P=Vrms*I
3)  P=Vrms^2/R
4)  Vpp = Vrms * Sqrt(2) * 2
5)  dB SPL = Sensitivity dB/mW * P
 
But most manufacturers stick to tradition and requirements of the FTC, and also avoid this discussion. Schiit, Garage1217, Cavalli, and a few others catering to this market are exceptions.
 
Amps usually have design trade offs to achieve target price point. A higher voltage output may have a higher noise floor unless greater effort (and cost) is allowed for the power supply, layout, amplifier topology etc. Output impedance of amps vary between designs. The one size fits all usually has switches to allow gain changes to manipulate these parameters to juggle the needs of different headphones and IEMs. My Cavalli Liquid Crimson fits into the one amp does everything (and very well too.) It still requires multiple outputs and a gain switch to manipulate parameters. It will handle IEMs to HE-6. That comes at a cost of $3K. My answer here can be considered incomplete at best. There are other places where this topic is discussed in much greater depth.

 

[bimmer100]

 
Here are two pieces that go into the nitty gritty of amp specs and compatibility with headphones:
http://nwavguy.blogspot.ca/2011/09/more-power.html
http://www.rayfes.com/caraudio/ampspec.php
 
Both readings are quite terse and technical, but are very interesting if you want to better understand specs, what they mean and how they can be useful (e.g. matching headphones and amps). The first link gives a number of computations, but there is the occasional typo which doesn't help understanding, and some computations are a tad confusing. They do discuss at length Vrms, Vpp, mW, and how to convert between the various measures.

Thank you, I will definitely read up on this tonight.
 
I'm a bit concerned mainly because of AB's comment I quoted. It sounds as if a powerful amp would not be ideal in some situations. I've tried so many amps and was so frustrated that I tried a new approach... just get a beast. So far i've not had any headphone or IEM sound bad with my setup. But of course, that's just my opinion. 

 

[landroni]

  I'm a bit concerned mainly because of AB's comment I quoted. It sounds as if a powerful amp would not be ideal in some situations. I've tried so many amps and was so frustrated that I tried a new approach... just get a beast. So far i've not had any headphone or IEM sound bad with my setup. But of course, that's just my opinion.

Which one did you get? Schiit's Ragnarok is being marketed for both "some" IEMs and desktop speakers. It should drive the HE-6 with watts to spare. And apparently should work just fine with efficient headphones like Grados.

 

[bimmer100]

  Reasonable question. I did forget to answer the question and edited that post to offer a bit more opinion on the question. Still not a full answer. Without knowing how loud in SPL the user wishes to listen, it is hard to answer. I will have to measure the Asgard 2. On my (rather long) list of things to do in my spare time.
 
Garage1217 does sort of publish the information if one looks at their power graphs, though you have to work backwards from the power at a given nominal impedance to find the Vrms and I (current.) The math is fairly simple and only uses:
 
1)  I=E/R (where E is Vrms in this case) Ohm's Law
2)  P=Vrms*I
3)  P=Vrms^2/R
4)  Vpp = Vrms * Sqrt(2) * 2
5)  dB SPL = Sensitivity dB/mW * P
 
But most manufacturers stick to tradition and requirements of the FTC, and also avoid this discussion. Schiit, Garage1217, Cavalli, and a few others catering to this market are exceptions.
 
Amps usually have design trade offs to achieve target price point. A higher voltage output may have a higher noise floor unless greater effort (and cost) is allowed for the power supply, layout, amplifier topology etc. Output impedance of amps vary between designs. The one size fits all usually has switches to allow gain changes to manipulate these parameters to juggle the needs of different headphones and IEMs. My Cavalli Liquid Crimson fits into the one amp does everything (and very well too.) It still requires multiple outputs and a gain switch to manipulate parameters. It will handle IEMs to HE-6. That comes at a cost of $3K. My answer here can be considered incomplete at best. There are other places where this topic is discussed in much greater depth.

Thank you AB, for explaining the math. I would love to learn more in time.  I would love to have my Master11 tested and scrutinized to understand it a bit more. Happy to loan it out if needed. I realize you're busy although wonder if it's of interest to you. I understand it has similar technology to Bakoon's Satri tech. Kingwa is pretty good about posting some of the specifications of this dac/amp combo. To my ears, it sounds more musical than most setups i've heard, and with any headphone/iem. It's not cheap, but it surely seems like a lot of bang for the buck being an all in one unit.