This will be an assessment and step-by-step dimensions associated with Schiit Saga passive/tube pre-amplifier.

20 Tháng Bảy, 2021

This will be an assessment and step-by-step dimensions associated with Schiit Saga passive/tube pre-amplifier.

it really is on type loan from the member who’s got waiting literally months for their review! The Saga costs USD $349 from Schiit direct with stock shipping plus tube. The tube provided with this device had been the Russian 68HC which can be their clone of 6N8S (dural triode).

The commercial design is typical of Schiit item but as always, with a new switch system and appears:

For reasons too embarrassing to spell out, I’d to start the machine and here, we noticed the analog amount control (which gets changed into electronic), possessed a notch that is nice it. I happened to be pleased they certainly were making use of such as that would steer clear of the volume control becoming loose, and then recognize the set screw continues the part that is round of shaft, maybe perhaps not flat!

Anyhow, back into the switches, the are microprocessor controlled and feel nice. Click the input one in the left and also you turn between five various RCA inputs. The turn on the proper chooses whether or not the Saga is really a easy pass-through with amount control, or via a working hybrid tube+solid state production stage pre-amplifier. The gain both in full situations is zero meaning whatever voltage you place in, is really what you can get away.

The quantity control is a stepped attenuator making use of a small number of relays and resistors. Comparable group of relays are accustomed to find the right input.

Let us go into dimensions and find out just just exactly how each mode executes.

Dimensions This being truly a pipe amplifier, we thought I measure I measure its performance in active mode since it driven on to observe how it changes:

While you see, performance is very stable. There clearly was a tremendously improvement that is slight one channel as much as about a moment but from then on, there is absolutely no huge difference also only at that magnification. This is an excellent thing than you have to as you don’t want to age the tubes any more.

I will be frequently packed with complaints about urban myths audiophiles think it. The above busted one of my own myths that tube products require significant warm up to get to stable performance in this case. @SIY had told me personally otherwise but needless to say, I didn’t pay attention.

With that from the method, let us have a look at our usual dashboard. To essentially judge the performance of this Schiit Saga in passive mode, we thought we show the indigenous performance for the Audio Precision APx555 on it’s own before routing the production through the Saga:

We come across the amount that is tiniest of distortion at 2 kHz (degree at -150 dB) and mains sound (degree at -145 dB).

There is certainly some sound around our main sign dress. I could be rid of that utilizing the digital (DAC) mode associated with the APx555 generator then again distortion increases. Anyhow, a SINAD is had by us of 122 dB only at that 2 volt production be2 Profily.

Routing the sign through Schiit Saga at maximum amount in passive mode we have:

There clearly was some mains leakage that could be as a result of ground cycle or leakage of this power for the active stage in Saga. In any event, this is certainly performance that is exemplary simply 2 to 3 dB of loss when compared with APx555.

I became securing to my seat anticipate massive fall in performance once I started up the pipe:

Wow, this might be extremely respectable! I have calculated Schiit DACs with far reduced performance. The offending distortion may be the 2nd harmonic at nearly -98 dB which sets the SINAD/THD+N. Additionally power associated surges however they are at -108 dB and lower so do not come right into play.

Overall, this might be one good showing so far!

Let’s measure regularity reaction at maximum volume:

The mode that is pass-throughin blue) is ruler flat, showing the superlative performance regarding the APx555.

We went the stage that is active means: 1) with standard 100k Ohm input impedance associated with the analyzer (green) and 2) 600 Ohm load regarding the analyzer. We come across there is some droop with 100k Ohm load beginning at 50 Hz and increasing to 2 dB at 10 Hz. This suggests a capacitor production phase which will have increasingly higher naturally impedance as frequencies decrease. Switching to 600 Ohm load emphasizes this and magnifies the problem considerably and artificially, providing us 16 dB of droop by 20 Hz.

The 600 Ohm impedance is basically the inverted form of our production impedance bend but why don’t we run the complete measurement to obtain the particular values:

Searching all of the real option to the best, the minimum impedance is 183 ohm. During the entry level of 20 Hz, impedance climbs to 3,130 ohm. Utilising the typical 10:1 guideline, your energy amplifier input impedance should really be at the least 30k Ohm in order to avoid regularity dependent/EQ modifications. Place more just, by using reduced input impedance energy amplifier after Saga in active mode, your low frequencies below 500 Hz or more will attenuate. This could accentuate all of those other range you might like, or perhaps not.

The passive mode has a unique dilemmas right here. Up to now on function we have actually held the quantity at max as to help keep the attenuator resistors off the beaten track. The minute you turn straight down the amount, you are placing amount that is varying of in the production course and thereby, increase impedance. This is actually the production impedance bend in passive mode with amount around 20percent:

The cursor are at 144 Hz showing an impedance of 2,760 ohm. This might be in comparison to simply 21 ohm impedance at max volume showing the 20 ohm production impedance of this APx555 analyzer.

Plotting a points that are few the quantity control gets us this:

So basically, any amount level not as much as 50% will probably boost the impedance considerably. Luckily the attenuation just isn’t frequency dependent and so the effect is certainly not there as there clearly was with pipe phase. But then turning down the volume may change the frequency response if the input impedance of the power amp changes with frequency and is less than 30k Ohm. Perfection in noise and distortion has this cost.

Conclusions i need to state, we developed a fondness with this small pre-amp. We have no concept why it myself as I would never use. It simply may seem like a neat mixture of features in a fairly low priced package. Then i don’t see a reason to not get and play with it if you are looking for its features and are mindful of drawbacks with respect to its varying output impedance. Make use of it as a nicely implemented switcher that is audio instance utilizing the amount control for fine tuning of max level.