Schiit Skoll Balanced Phono Stage Review

[mike70]

Actually, people who are using a rumble filter for the right reason have pumping woofers, so more is better than less in that situation.

in my experience ... big pumping woofers generally happens with badly warped records ... or the analog system have something wrong (bad compliance cartridge / tonearm, wear in bearings, inadequate base, etc etc).

i don't have rumble filter in my analog system and i use tts since 70s ... in the right context i never had pumping woofers, never.
my experience ... many people don't remember that turntables are mechanical devices, far (very far) from ICs with opamps and some cables inside.

 

[Angsty]

Actually, people who are using a rumble filter for the right reason have pumping woofers, so more is better than less in that situation.

One of our industry experts, Frank Dernie, points out (in a different thread) another physics-based reason to have a high pass filter for low frequencies…

SOTA Pyxi Phono Stage Review

@amirm - Regarding the ifi Zen. Can you explain what changed with test conditions to pull it from the rankings? Just trying to understand the evolution of the phono testing protocols. I just looked at the review and I don't see a reason to exclude it. Yet it was taken out of the list to be...

www.audiosciencereview.com

 

[mike70]

One of our industry experts, Frank Dernie, points out (in a different thread) another physics-based reason to have a high pass filter for low frequencies…

SOTA Pyxi Phono Stage Review

@amirm - Regarding the ifi Zen. Can you explain what changed with test conditions to pull it from the rankings? Just trying to understand the evolution of the phono testing protocols. I just looked at the review and I don't see a reason to exclude it. Yet it was taken out of the list to be...

www.audiosciencereview.com

i´m wondering why in the LPs only era of boites / clubs, that doesn´t have filters, and the big, big 16"/ 20" (or more) woofers doesn´t have that effect ... or the older Altec / JBL home speakers doesn´t have the effect also. And i use a filterless preamp with my new cartridges doesn´t have the effect ... much more, the engineer that made the preamp talk against filters (phase problems) and is also another "expert".

Sure i'm not an expert ... but i don't talk about theory, i talk about practice indeed .. i believe in results (observable results, not mind tricks, of course).
Woofer pumping exists? yes.
Is about something natural that always happens and only a filter can fix? Not for me.
in the right context i can´t see any woofer pumping, even with that "cartridge natural flaw, blah blah".

 

[Angsty]

i´m wondering why in the LPs only era of boites / clubs, that doesn´t have filters, and the big, big 16"/ 20" (or more) woofers doesn´t have that effect ... or the older Altec / JBL home speakers doesn´t have the effect also. And i use a filterless preamp with my new cartridges doesn´t have the effect ... much more, the engineer that made the preamp talk against filters (phase problems) and is also another "expert".

Sure i'm not an expert ... but i don't talk about theory, i talk about practice indeed .. i believe in results (observable results, not mind tricks, of course).
Woofer pumping exists? yes.
Is about something natural that always happens and only a filter can fix? Not for me.
in the right context i can´t see any woofer pumping, even with that "cartridge natural flaw, blah blah".

I don’t know when “rumble filters” became out of favor, but neither of my last two phonos had them and I have not experienced a problem.

What I can say is that it appears that nothing “good” happens below 30 Hz with vinyl. Whether it is rumble, cartridge/arm/headshell resonance, warps, recorded noise, or acoustic feedback, all of those can be detrimental to playback below a 30-40 hz cut-off frequency.

I do think there is another question about why these problems are not universally experienced

 

[Digital1955]

I had a chance to use and take some measurements on a recently purchased Skoll. I took some measurements with a signal generator, and some using my turntable setup as a source. When running a MC cartridge (AT33PTG2) and the Skoll unbalanced (100Ohm, 50pF, 60dB), I did observe more noise in the left channel than the right. The levels are well below playing levels, but if you would turn the volume up to seek out the noise floor, yes, I found more noise in the left channel. This is with the
stylus up, not playing:

I swapped the leads around to make sure the noise was tied to the Left channel on the Skoll. And it was for me.
I swapped in my phono preamp (Cambridge Audio CP2) into the same setup and didn't observed any imbalance in the noise floor. Nor did
I have so much 60Hz and harmonics on either channel.


Another observation I had about the Skoll that hasn't been mentioned is the difference in gain on available on the unbalanced connections.
I know Amir's measurements show the balanced connections, so I measured the gain on the unbalanced connections. The manual doesn't
mention any difference, however, I did measure 6 dB less gain on the unbalanced connections. I understand there is normally a 6 dB difference
between these connection types, however, its important to note. 6 dB is a massive difference if you aren't expecting it.

For instance when I had my signal generator set to to 0.005 volts, with the Skoll in the 40dB setting, I was only measuring 0.2505 volts output which is 34dB. This means when using the unbalanced connections you almost have to go up to the next gain setting to get closer to your target gain. Would have been nice if that
was spelled out in Amir's reviews and more importantly, in the manual.

 

[Angsty]

Would have been nice if that
was spelled out in Amir's reviews and more importantly, in the manual.

To be fair, Amir did point to reduced gain when using the RCA outputs but he did not quantify how much as you did.

I’m of mixed feelings about this Skoll. With the (repeated) reports of noise in the left channel, the high cutoff point for the LF filter and now the 6dB gain differential between outputs, I ultimately voted it as “not terrible”. It seems as if it can do the job, but I’d only feel compelled to look at it if I were using balanced connections and a high output cartridge.

 

[mike70]

The ifi zen seems to be the best price / performance for balanced output preamp.
A pitty you can't find it in black colour, only silver :-(

Other option for a little more than Skoll ... project DS3 B

 

[gxleetw]

To be fair, Amir did point to reduced gain when using the RCA outputs but he did not quantify how much as you did.

I’m of mixed feelings about this Skoll. With the (repeated) reports of noise in the left channel, the high cutoff point for the LF filter and now the 6dB gain differential between outputs, I ultimately voted it as “not terrible”. It seems as if it can do the job, but I’d only feel compelled to look at it if I were using balanced connections and a high output cartridge.

Actual owner chiming in here. As Digital1955 pointed out, the noise floor well below the playing level (or surface noise), so why would it matter if one channel is slightly noisier than the other? Of course buzzing is another question, but mine is problem free and I would say Skoll is by far one of the quietest phono preamps I own or heard.

My cartridge output is 0.4mv, which would be considered low output. but I don’t feel gain is an issue. Even with my preamp in the unity gain mode, the volume knob is still in the range allowing meaningful adjustment. I also want to point out that I don’t think there is any perceivable tonal changes among the gain settings on the Skoll.

 

[Digital1955]

Actual owner chiming in here. As Digital1955 pointed out, the noise floor well below the playing level (or surface noise), so why would it matter if one channel is slightly noisier than the other? Of course buzzing is another question, but mine is problem free and I would say Skoll is by far one of the quietest phono preamps I own or heard.

My cartridge output is 0.4mv, which would be considered low output. but I don’t feel gain is an issue. Even with my preamp in the unity gain mode, the volume knob is still in the range allowing meaningful adjustment. I also want to point out that I don’t think there is any perceivable tonal changes among the gain settings on the Skoll.

0.4mV is on the high side for a MC. Typically you'd need around 60dB of gain for 0.25mV. Your cartridge has a bit more output at 0.4mV
so you need less gain. Assuming you are set to 60dB on the Skoll (and using unbalanced), this means you have 54dB of gain, which is pretty close to ideal for your 0.4mV output. In other words, this setup happened to work out for you.

 

[formdissolve]

Ended up purchasing some 5-pin DIN to balanced XLR for my TT (Technics SL-1210 Mk2 with Jelco SA-250 + Hana ML). Yes, they were expensive but wanted to go full XLR for my phono chain.

BJC states: "For the less usual situation where you're running out of a turntable DIN into XLR inputs, our recommendation is Canare MS203-2BS, a two-pair cable with shielding both on the two pairs and on the whole bundle; we telescope the overall shield, tying it only to the DIN end, and ground the pair shields to the same pin at the DIN end as well as to pin 1 of the XLR output. You shouldn't ordinarily need an additional grounding wire with this configuration, so we've left it off."

I plugged them in and noticed a very slight hum at 40dB gain. At 50dB+ gain, it's a massive ground hum. Are these wired to assume there's another ground inside the tonearm to the TT chassis or something? I noticed there are other (and absurdly expensive) 5-pin DIN to XLR that DO have a ground wire, so wasn't sure what the deal is with the BJC cables.

This ground hum was not there with my old RCA din cable (BJC MSA-1) with ground wire, so I reverted back to that and it sounds fine, so I'll just keep using that. Just curious if anyone has any insight to the ground issue using a 5-pin DIN with those BJC XLR cables.

 

[JP]

Is the turntable chassis grounded to your phonostage as well?

 

[formdissolve]

Is the turntable chassis grounded to your phonostage as well?

Using the RCA DIN cable, it has a ground connected to the tonearm (via the DIN connector) and the ground wire. The tonearm is not grounded to the chassis, just connected to an armboard. I assumed the same would work for the XLR seeing how the BJC XLR cable is wired..

Just realized this was posted on the review.. meant to post it on the other Skoll thread. My bad!

 

[JP]

Using the RCA DIN cable, it has a ground connected to the tonearm and the ground wire. The tonearm is not grounded to the chassis, just connected to an armboard. I assumed the same would work for the XLR seeing how the BJC XLR cable is wired..

I get what BJC did - it's the same way I run my arms, though they're RCA with a ground pin at the arm. That ground goes to pin 1. However the chassis has to be grounded too. A friend had a similar issue a couple weeks ago with his SP-10MK3 - once he grounded the chassis to the phone stage as well all his noise issues disappeared. Not promising it's a fix, but it's a box that needs checked.

 

[formdissolve]

I get what BJC did - it's the same way I run my arms, though they're RCA with a ground pin at the arm. That ground goes to pin 1. However the chassis has to be grounded too. A friend had a similar issue a couple weeks ago with his SP-10MK3 - once he grounded the chassis to the phone stage as well all his noise issues disappeared. Not promising it's a fix, but it's a box that needs checked.

I'll try that tonight! Found a link that helps.. I recall the stock tonearm being grounded to the pitch fader. Thanks JP

 

[4D_Coaxial_Cube]

I had a chance to use and take some measurements on a recently purchased Skoll. I took some measurements with a signal generator, and some using my turntable setup as a source. When running a MC cartridge (AT33PTG2) and the Skoll unbalanced (100Ohm, 50pF, 60dB), I did observe more noise in the left channel than the right. The levels are well below playing levels, but if you would turn the volume up to seek out the noise floor, yes, I found more noise in the left channel. This is with the
stylus up, not playing:

View attachment 348058


I swapped the leads around to make sure the noise was tied to the Left channel on the Skoll. And it was for me.
I swapped in my phono preamp (Cambridge Audio CP2) into the same setup and didn't observed any imbalance in the noise floor. Nor did
I have so much 60Hz and harmonics on either channel.


Another observation I had about the Skoll that hasn't been mentioned is the difference in gain on available on the unbalanced connections.
I know Amir's measurements show the balanced connections, so I measured the gain on the unbalanced connections. The manual doesn't
mention any difference, however, I did measure 6 dB less gain on the unbalanced connections. I understand there is normally a 6 dB difference
between these connection types, however, its important to note. 6 dB is a massive difference if you aren't expecting it.

For instance when I had my signal generator set to to 0.005 volts, with the Skoll in the 40dB setting, I was only measuring 0.2505 volts output which is 34dB. This means when using the unbalanced connections you almost have to go up to the next gain setting to get closer to your target gain. Would have been nice if that
was spelled out in Amir's reviews and more importantly, in the manual.

I really appreciate the effort you went through to report this data. I was considering the Skoll as I have been pretty happy with the Freya + pre-amp. I really thought that I would like the tube circuit in it, but I have been enjoying it without the tubes turned on. I thought Schiit had very good quality control considering American made and most reviews point us to pretty good backing of such an idea. I wonder what the deal is with this Skoll unit.

 

[EJ3]

...and there's the answer to my question. Thanks for the review. Schitt is churning out new products at quite a clip lately.

GOOD NEW PRODUCTS.

 

[EJ3]

People like vinyl. They like the ritual, the jacket art, and I think they like the limited playback time too because they take a little rest from listening every 20 minutes or so to change the album or flip it over.

Drink a coffee for each side turnover. By the time you finish 4 sides, you should be ready to go do something else (maybe work on the "Honey Do" list).

 

[EJ3]

In theory? Or in a real recording played in a real room / speakers?

In theory never.
In real recordings, you can check the online dynamic range recording databases by format.
And .. if we take that recording to room / speakers ... let me say I have many records with better sound than CDs ... many.

We're using science here, don't misunderstand, but theory and practice are only equals in theory

So that's why medical Dr.'s call what they do a "practice"?

 

[EJ3]

Their names are mostly Norse, or derivatives of.

View attachment 319171

Over here, skol, skolling or skolled refers to downing a beer in one go. Chugging in the US?

Yes. Chugging1
AND here (in the USA) a Skoal ring refers to the ring made into your back pocket by the can of chewing tobacco you constantly carry.

Also here: the band "Canned Heat" is named for the slang for Sterno (a brand of jellied, denatured alcohol sold in and meant to be burned directly in its can. Popular both in commercial food service and home entertainment, its primary uses are in as a fuel for heating chafing dishes in buffets and serving fondue. Other uses are for portable stoves and as an emergency heat source. It is also used with toy and model steam and other external combustion engines.

The flame is typically lighted with a match or lighter and extinguished by placing the lid over the can to starve it of air, though any noncombustible cover will do).

I liked their LP's, which sound better with a good PHONO stage.

 

[EJ3]

There’s surprisingly little real musical info below 50 Hz and in room resonances easily make up for any 2dB drop off in response. Worse, below 50 Hz, there is often acoustic rumble on older recordings caused by air currents in large recording spaces - lopping off stuff below 50 Hz can help that and it ultimately makes very little difference to the perceived sound other than remove the rumble.

You can read about this here (follow the links to the audioXpress articles Part 1 and Part 2))

https://audioxpress.com/files/attachment/2735

https://audioxpress.com/files/attachment/2736

The low note on an 88 key piano is at 27 Hz, if I am correct. I think that it would be worth it to have an FR that extends at least to there.