[johnjen]

After seeing what the regulator did for my Mutec I ordered a 5v version for my D16. The issue was then to figure out a DC source that was just about 6 volts. I was already using the variable outputs of my 2 HDPlex LPSs and I did not feel like spending more money. The thought came to me that perhaps I could re-purpose my 5V Teradak by seeing if it had a large enough DC input and an adjustment pot. Luckily it does. The transformer is good for 9 volts AC and it does indeed have a blue adjustment pot. I set it for about 5.8 volts to account for the dropout voltage of the regulator. Waiting for the regulator now.

Seeing how the Teradak could be tweaked made sense as I always thought that it ran very warm running the 5V and probably 1 amp that my D16 needed. It was probably throwing away 12.6(9*1.4) - 5v = ~7.6 volts as heat. Should be slightly cooler now. If this works I might try adding another 6V regulator is series and turn up the Teradak output further to 7V. Teradak has a little sticker on their supply stating that opening it will invalidate the warranty. I can understand this but I also bet that they do not want users to tweak the voltage themselves or know how easy it is. They should sell it as 5-9V adjustable and put the pot on the back of the case like HDPlex does...

Fun stuff!

To help with the heat from the teradak you can run it at an even higher output voltage and then have the secondary regulator drop that higher voltage down itself.

An example.
The Teradak drops the voltage by 7.6v x 1amp (1 amp used for ease of this discussion) = 7.6watts of heat with an output of 5Vdc
If the Teradak drops the voltage by 5v x 1amp = 5 watts of heat (a reduction by ≈1/3) with an output of 7.6Vdc.
Which in turn means the secondary regulator now drops that input voltage of 7.6Vdc to 5Vdc or 2.6V x1 amp = 2.6watts.

IOW spreading the voltage drop more evenly over 2 regulators means less heat for the primary regulator and a bit more thermal stability for the 2nd regulator as well.

And of course these voltage drops can be adjusted to suit your needs and setup as needed.

Just a thought or 2.

JJ

 

[mourip]

To help with the heat from the teradak you can run it at an even higher output voltage and then have the secondary regulator drop that higher voltage down itself.

An example.
The Teradak drops the voltage by 7.6v x 1amp (1 amp used for ease of this discussion) = 7.6watts of heat with an output of 5Vdc
If the Teradak drops the voltage by 5v x 1amp = 5 watts of heat (a reduction by ≈1/3) with an output of 7.6Vdc.
Which in turn means the secondary regulator now drops that input voltage of 7.6Vdc to 5Vdc or 2.6V x1 amp = 2.6watts.

IOW spreading the voltage drop more evenly over 2 regulators means less heat for the primary regulator and a bit more thermal stability for the 2nd regulator as well.

And of course these voltage drops can be adjusted to suit your needs and setup as needed.

Just a thought or 2.

JJ

Sounds like a good plan. I guess that the trick is to not expect the secondary boards to dissipate too much heat as they have virtually no heat sink?

 

[johnjen]

In part that is true, but small amounts of heat can actually help stabilize the operation of the regulator since it will make for a more stable thermal environment.
The load itself varies but adding a 'constant' amount of 'background' heat flow can provide more stability thermally speaking.

JJ

 

[johnjen]

So a status report.

During my vaca I left my entire system on and playing the entire time.
As such I added ≈700hrs to the total accumulated hrs which amounted to ≈2500hrs when I returned.
This is sufficient for ALL of the rhodium connectors to fully settle in.
And of course the re-cooking of all of my cables since returning has helped a whole bunch as well.

The results thus far are a noticeable increase in I5 (Intelligibility,) an increase in coupling and definition in the bottom octaves.
And in the mid range there is a greater degree of focus and cohesion and coherence.
Along with improvements in T3, (ToeTappingTime) HB&W (Head Bobbing & Weaving), tLFF (the Listener Fatigue Factor), Moar Is Less, SDSG (SuperDuperSuperGlue), the overall SQ has risen to new levels of REALNESS.

Just like I like…!

JJ

 

[johnjen]

So I just ordered a new set of speakers to replace my Dayton $40 bookshelfs.
I figured it was time to up the SQ of my nearfield setup.

I ordered a set of Ascend Acoustic Sierra Luna mini bookshelfs, which are very similar to their Sierra 2's only using a smaller mid range driver in a smaller case.
I don't know how long it will take to get here but I'm figur'n it'll be my xmas present to me.

The specs and measurements are most impressive and my Rok amp should have plenty of power to drive them to 'satisfactory' levels.
It has a RAAL ribbon tweeter and a 4.5" SEAS long throw mid driver, with a Freq Response of 60 - 27KHz ±3db.
The horizontal and vertical dispersion and decay response is most impressive as well.

And to top it off (if I feel so inclined) they make sub woofers which work well with these mini monitors.
So I might be able to get my pants a flapp'n, a new experience for me in my home setup.

This should enable a MAJOR step up for my home speaker setup.

I'm jazzed…

JJ

 

[gefski]

So I just ordered a new set of speakers to replace my Dayton $40 bookshelfs.
I figured it was time to up the SQ of my nearfield setup.

I ordered a set of Ascend Acoustic Sierra Luna mini bookshelfs, which are very similar to their Sierra 2's only using a smaller mid range driver in a smaller case.
I don't know how long it will take to get here but I'm figur'n it'll be my xmas present to me.

The specs and measurements are most impressive and my Rok amp should have plenty of power to drive them to 'satisfactory' levels.
It has a RAAL ribbon tweeter and a 4.5" SEAS long throw mid driver, with a Freq Response of 60 - 27KHz ±3db.
The horizontal and vertical dispersion and decay response is most impressive as well.

And to top it off (if I feel so inclined) they make sub woofers which work well with these mini monitors.
So I might be able to get my pants a flapp'n, a new experience for me in my home setup.

This should enable a MAJOR step up for my home speaker setup.

I'm jazzed…

JJ

Yggy/Rok + speakers? The other people in the house (and the neighbors) will just have to adjust to the 20 hour sessions.

 

[johnjen]

Yeah they'll learn the true meaning of suffering…
All the while gruv'n to the tunes…

And really I doubt these speakers will equal my 800's, unless I get a sub and then probably only to the degree the visceral impact in the bottom end gets boosted.
Of course I might be in for a shock/surprise after they show up and settle in, as to how good they may actually be.
And I'll find out if the subwoofer section of jriver is of any help, or not.

Still, they will definitely be a step up for sure.

JJ

 

[johnjen]

So here are a couple interesting measurements of these speakers

For a 4.5" woofer that is really good low end response, but it's the midrange where it will really shine.

JJ

 

[johnjen]

and

Notice how fast the driver stops. And the crossover is at 2200Hz.
This is rather impressive, at least from a measurement stand point.

We'll see how they sound in a few days.

JJ
and these graphs are courtesy of Ascend Acoustics.

 

[mourip]

Over on CA I found out about the LT3045 regulator board. It is ironic because I believe that RB2013 was talking about it here earlier this year before he left HF.

This is a very small DC to DC fixed voltage regulator with very low noise. They are sold on EBay and you have a choice of the fixed output voltage. It also has a low dropout voltage of only about .7v and comes in .5 and 1.0 amp versions. Mine came today and I installed it in my Mutec 3+ USB which was already running off of an HDPlex LPS from it's 9v variable output which I had set to 6.3v. Switching from the SMPS to the LPS had made a nice change.

Today I raised the output to 6.8v and installed the 6v@1A version of the LT3045 board. I also retained the modest sized electrolytic that I had been using for local bypassing of the DC input inside the chassis.I was hoping to at least break even for my effort but found that the improvement was really, really good. The noise floor must have dropped quite a bit because more details were brought out. I also found an improvement of perceived tonal "correctness".

I received my second LT3045 regulator this week and installed it in my Focusrite D16 which was already running off my HDPLEX LPS. It is a 5V regulator and I decided to repurpose my Teradak 5v LPS which can easily be adjusted to a higher voltage using the small blue pot inside. The rcore transformer in it is rated for 9v so I assume that after the full bridge rectifier it is putting out 9v x 1.4 = ~12.6v unregulated DC. I turned it up to 5.8v to allow for the .7v dropout and all is well. I already had a 2200mf in the D16 for a local bypass and so kept it.

To be honest it is a little hard to evaluate the effect it had as I have a new amp in my system which I am helping Linear Tube Audio beta test and so my system is in flux a bit. I am sure that it will help as it certainly made a nice difference in my Mutec USB. I may try putting another one in series later. Hope springs eternal

 

[Luckbad]

I went ahead and built the @atomicbob Noise Nuke today because the parts arrived shortly before I got off work.

It's too soon to declare it the best bang-for-the-buck upgrade to any DC powered headphone amplifier, but I really do think I'm hearing subjective improvement.

My parts list was a little different from atomicbob's:

• Choke: Hammond 155B 6mH 2A
• Capacitors: Nichicon FW 6800uf 63V (KW were not in stock anywhere)
• Enclosure: Mammoth 4S1590BBT w/ black texture powdercoat
• DC Jacks: Switchcraft PC722A
• Odds & Ends: A pair of 1" cable tie mounts, cable ties, heavy duty velcro, a bit of wire, solder, some padding and electrical tape for the choke to stay snug and comfortable.

The listening station:

Lynx AES16e → Neutrik AES/BNC transformer → Schiit Bifrost Multibit → Garage1217 Project Sunrise III (w/ Noise Nuke) → Sennheser HD650 (w/ phase reversal trick, which I think is a @johnjen special)

Some glamor shots of the atomicbob Noise Nuke paired with the Garage1217 Project Sunrise III, cleaning up the power from the Mean Well switching power supply (they mean well, but it's still an SMPS... har har...):

 

[johnjen]

If i were to make one of those I'd put some smaller bypass caps across those electrolytic's using the 100:1 rule.

13,600 : 136 : 1.36 : 0.0136.

Of course you can round up or down to suit, based upon the availability of usable caps.
IOW the exact rating of the cap can be adjusted (the need to stay at the 100:1 ratio isn't strict).
And I'd be using high voltage (100, 200, 400 etc voltage rated caps).

This will help reduce the high freq spurious noise and also the ability to dump current into the load more quickly.

JJ

 

[johnjen]

So following in MusiqBoys footsteps I just got done adding 2 of the LT3045 regulators to the 2 Mutec 3+'s, right at their mainboards.
This is after using a pair of LT3045 regulators in the LPS I built to power these 2 digital devices.
So in effect I have a 2 stage voltage regulator setup with the 2nd stage installed locally at the load itself.
I also have added a 8µfd with a 0.01µfd bypass at the mainboard of each 3+ as well.

This is the 3+ USB mainboard with the added voltage regulator

Thus far the SQ has taken yet another step up in every meaningful category I pay attention to.

I measured the noise across those bypass caps at, (using the Tektronix 468 scope with it's digital memory modes of capturing and measuring the noise on top of the +5Vdc being supplied by the 2nd stage voltage regulator.
Norm = 4.6 to 3.76mv (high to low frequency sweep rates)
Average = 0.77 to 0.41mv (high to low frequency sweep rates)
Envelope = 9.8 to 7.2mv (high to low frequency sweep rates)

The results are even noticeable on my new Ascend Acoustic Sierra Luna Mini Monitors.
And they are being somewhat limited since I'm using a cheap (as in $20) Lepai class T (really class D) 8watt/ch amp.
So if I can hear these sorts of changes thru a cheap, under powered, digital amp, I'm really looking forward to what they will reveal when I power them with my Rok amp.

JJ

 

[johnjen]

So Musiqboy have you mounted the 2nd stage regulators inside your 3+'s yet?
And if so did you notice any difference from having them be external vs. internal?

Just curious.

JJ

 

[Muziqboy]

I have both regulators installed in a project box with a 2.1mm dc plug on the output.
It is more convenient for my application so don't know if there is a difference between external vs. internal mounting.
But I did notice and heard the improvement in using the series regulator configuration as I have mentioned to you before.