Fosi Audio Box X5 Phono Preamp Review

[Splainder]

I have the Art DJ pre II, its worth the upgrade?
My stylus is a Nagaoka pm110

​

 

[joqueval]

Hello.
I also have the Art DJ (I have several) and the X5.
Although the Art sounds great, the X5 is superior.
Using a Technics SL 1210 M5G and an Ortofon Concorde DJ cartridge

 

[Muddywaters]

I have the Art DJ pre II, its worth the upgrade?
My stylus is a Nagaoka pm110

​

Define worth it? It’s complicated.

To really compare them you’d need to control for the differences in their input capacitance and how that interacts with your choice of cartridge. And, account for differences in output. Level matching, regularly brought up around these parts is necessary, in other words, control some variables to make any valid judgements. No peeking

The post above is lacking in detail (not picking on them) just pointing out that fact. It’s a common occurrence on the interweb, even here. Interestingly the Ortofon carts (mm) generally have a recommended loading capacitance much higher than, as an example, Audio Technica. Ortofon DJ’s typically suggest 200-600 pf. AT carts want 100-200 or better yet, lower some perform much better.

Concorde MKII DJ

The Concorde DJ is considered the jack-of-all-trades, boasting accurate sound reproduction and excellent groove handling. Not only does the cartridge have a most sufficient tracking ability, it also provides the DJs with the most needed stringency and very low record wear.

ortofon.com

It’s in the realm of possibility adding the capacitance of the users cables to the Fosi’s ~150pf by itself they are well up in the sweet spot for the recommended range of 200-600pf. It wouldn’t be a stretch that using a Ortofon DJ would ‘sound’ better but not because it is ‘better’ necessarily. Maybe the Fosi’s sensitivity is lower and output is louder? Needs to be accounted for.

The LP, phono chain has some arcane requirements if you want optimize playback. The high capacitance of the Fosi eliminates it from some consideration. It’s difficult to impossible without surgery to lower the device capacitance. Relatively easy to raise your Art to accommodate loading different cartridges. If having more cartridge choice is important to the end user it should be a consideration.

Also tests regarding noise levels between your two devices in question aren’t a complete picture here since the characteristics aren’t tested with an actual cartridge loading the circuit. There’s been some discussions pointing that out. There’s also a separate thread discussing testing accounting for some ‘generic’. Plus it will vary again due to cartridge selection.

Sorry for the long reply.

I suspect if things were tightly controlled and optimized it would be difficult to choose one over the other but that depends on the loading needs of your cartridge.

*edit to add a word (is)

 

[Muddywaters]

@Splainder I neglected addressing your specific cartridge the MP-110, apologies.

Nagaoka carts are a slightly different breed than the mm’s. MP stands for moving permalloy. Rather than magnets attached to the back end of the cantilever,(opposite the stylus end), a cool metal composed of molybdenum, nickel and iron I believe, flop forth and back while the coils and a strong samarium cobalt magnet are in a fixed position. In essence a variation on moving iron, MI. Grado’s, B&O among others are bedfellows.

Recommended load capacitance from Nagaoka is 100pf. Ive seen people run them all over a range though. Using the Fosi would leave you way over budget even without taking into account your cables from your table to the phonostage and the arm and possible headshell leads.

That said the moving iron variants seem to not react frequency response wise as readily to capacitance loading in my experience but I’m not qualified to say why. I could be way off base. Perhaps the cartridge data base here and folks in the dark corners of the phono part of the forum here have more insight.

I’m partial to Nagaoka to a degree. I have an MP-50 using the current MP-500 stylus and your cart’s predecessor the MP-11 body using the MP50 stylus and sometimes the MP500 stylus. I have a lot of cartridges from 55 years of collecting. MP500 would be one of my desert island choices if forced to decide, of currently available production.

Save that money you would have spent on the Fosi and scrounge some more cash for the upgrade to the fine-line tip and boron cantilever of the 500 stylus. That would be a better deployment of capital and better chance of noticeable upgrade to your vinyl playback. Depends how deep down the rabbit hole you want to go.

Better yet upgrade speakers or your room for more enjoyment.

Hope this helps.

 

[mike70]

I agree ... transducers and acoustics are the weak points in audio, not the electronics.

A better cartridge/stylus or speakers / room interaction improvement is what really worth, other stuff is only marginally audible.

 

[Splainder]

Thank you Muddywaters.
You guys are righ, I think Im going to save money for a better pair of speakers

 

[Boltman92124]

Hi DSJR!

And yup, we did. Nice to see you here, too.

Well, and no, I haven't - but I can nevertheless explain these output voltages: Lowbeats simply has used the DIN 0 dB mark as reference, so the corresponding modulation velocity is 8 cm/s (peak and in 45°/stereo modulation) or respectively 11.3 cm/s (also peak, but in lateral/mono modulation). Hence the measured 9.4 mV (Red), 10 mV (Blue and Black) and 10.8 mV (Bronze) would convert to not quite 5.9, 6.3 and 6.8 mV at the usual 5 cm/s (peak and in 45°/stereo modulation). So a bit hotter than specified by Ortofon, but just a tad over +2.6 dB hotter than specified in case of the 2M Bronze - rather than not quite +6.7 dB hotter, as it might appear at the first glance.

That's a general problem with cartridge output voltage specs, btw. For instance several Japanese manufacturers (including Denon, for example) tend to specify their cartridges at the JIS 0 dB mark instead, which also is 5 cm/s peak, but in lateral/mono modulation only - and hence would equal not quite 3.54 cm/s peak in 45°/stereo modulation. So one has to heed the "fine print", when comparing. Provided one can find it, that is - if not, one can never be quite sure, whether one might not be comparing oranges to grapefruits or mandarines rather than oranges to oranges.

Greetings from Munich!

Manfred / lini

Hey Lini! Another VE peep here. In the case of the Concord MK2's, when they specify 8.5 or 10mv output (Club and Digital), is that correct? They certainly play louder than my 5mv carts, that's for sure. Also, you mentioned dynamic headroom. Does this Fosi compare to something like Darlington Labs (which has 4-6db of headroom)? Or will it overload with a 10mv cart? If you know.

 

[joqueval]

Define worth it? It’s complicated.

To really compare them you’d need to control for the differences in their input capacitance and how that interacts with your choice of cartridge. And, account for differences in output. Level matching, regularly brought up around these parts is necessary, in other words, control some variables to make any valid judgements. No peeking

The post above is lacking in detail (not picking on them) just pointing out that fact. It’s a common occurrence on the interweb, even here. Interestingly the Ortofon carts (mm) generally have a recommended loading capacitance much higher than, as an example, Audio Technica. Ortofon DJ’s typically suggest 200-600 pf. AT carts want 100-200 or better yet, lower some perform much better.

View attachment 447244

Concorde MKII DJ

The Concorde DJ is considered the jack-of-all-trades, boasting accurate sound reproduction and excellent groove handling. Not only does the cartridge have a most sufficient tracking ability, it also provides the DJs with the most needed stringency and very low record wear.

ortofon.com

It’s in the realm of possibility adding the capacitance of the users cables to the Fosi’s ~150pf by itself they are well up in the sweet spot for the recommended range of 200-600pf. It wouldn’t be a stretch that using a Ortofon DJ would ‘sound’ better but not because it is ‘better’ necessarily. Maybe the Fosi’s sensitivity is lower and output is louder? Needs to be accounted for.

The LP, phono chain has some arcane requirements if you want optimize playback. The high capacitance of the Fosi eliminates it from some consideration. It’s difficult to impossible without surgery to lower the device capacitance. Relatively easy to raise your Art to accommodate loading different cartridges. If having more cartridge choice is important to the end user it should be a consideration.

Also tests regarding noise levels between your two devices in question aren’t a complete picture here since the characteristics aren’t tested with an actual cartridge loading the circuit. There’s been some discussions pointing that out. There’s also a separate thread discussing testing accounting for some ‘generic’. Plus it will vary again due to cartridge selection.

Sorry for the long reply.

I suspect if things were tightly controlled and optimized it would be difficult to choose one over the other but that depends on the loading needs of your cartridge.

*edit to add a word (is)

Hi.

Interesting technical input.

Perhaps I could have made some audio captures of the two preamps, but to the question of which one sounds better, my answer is based on experience.

In short I could compare it with two vinyls with the same song and different pressing, as a quick comparison.

About the concorde format, it really simplifies the connection and alignment of the capsule, it must be horrendous to have a good capsule and make a bad adjustment.

 

[Tangram]

Hi.

Interesting technical input.

Perhaps I could have made some audio captures of the two preamps, but to the question of which one sounds better, my answer is based on experience.

In short I could compare it with two vinyls with the same song and different pressing, as a quick comparison.

About the concorde format, it really simplifies the connection and alignment of the capsule, it must be horrendous to have a good capsule and make a bad adjustment.

The AC to AC power supply, not AC to DC ! And inside.

 

[Boltman92124]

Fosi’s ~150pf by itself

So this Cap spec for the Fosi will put it out of spec for basically all AT cartridges once all cabling is added. Is the capacitance adjustable down to 100pf by chance?

 

[Muddywaters]

Hi.

Interesting technical input.

Perhaps I could have made some audio captures of the two preamps, but to the question of which one sounds better, my answer is based on experience.

Audio capture, level matched, blind would be a good approach. Put them in Foobar and run an ABX. Keep in mind without leveling the playing field by adding 100pf of capacitance in-line to the Art phono you may hear a difference solely due to the capacitance mismatch.

Not sure what ‘experience’ means or really has to do with it. Lots of people ‘hear’ improvement's when none exist or if they know what’s playing. Not saying that is necessarily the case but testing eliminates the potential biases.

Many years ago when I acquired digitizing capability I put a gaggle of phono pre’s through a series of recording three diverse tracks. Some pre’s multiple times with linear power supplies vs wall wart even battery in one case. This however proved the differences pronounced while being aware of which was playing, mysteriously disappeared when blinded and level matched.

There were some differences but not readily heard in casual listening. Only one person identified a particular one. It took very focused dissection of the rips to do so. Includes me finding it way demanding.

In short I could compare it with two vinyls with the same song and different pressing, as a quick comparison.

Not following here. Why would you test with different pressings? Your audio capture suggestion would be the way to go using the same lp.

About the concorde format, it really simplifies the connection and alignment of the capsule, it must be horrendous to have a good capsule and make a bad adjustment.

You are correct about it being a simpler, easier option. Plug and go.

Many people choose other alignment schemes for technical reasons. With your fixed alignment you get what’s given. Using the spherical diamond it is more forgiving of alignment variation vs fine line, line contact and Shibata tipped cartridges. They however provide better playback on inner grooves and lower distortion.

To get a horrendous result is surprisingly not easy with simple procedures. Otherwise lp playback forums would be buried with “my new cartridge sucks” cries.

Depends on the depth of the rabbit hole again.

 

[Muddywaters]

So this Cap spec for the Fosi will put it out of spec for basically all AT cartridges once all cabling is added. Is the capacitance adjustable down to 100pf by chance?

Short answer yes. ***edit to add correct for being high on the capacitance.

You’ll definitely be running an AT hotter on the higher frequencies. Let’s be clear I’m not saying it’s going to be “horrendous” or in unlistenable. Some of us old guys might like it

Take a gander in the phono cartridge library here to see what can be. Some really good info and testing being done. You possibly can find your chosen cart has some testing, some cases multiple times with different loadings.

To get a Fosi X5 with lower capacitance would require surgery. I’m not qualified to speak on that possibility. It doesn’t have a switchable option. In some cases designs with higher capacitance are chosen due to minimize rfi and emi interference. Sometimes builders don’t recognize there can be legitimate requirements for lower capacitance.

Good luck.

***edit for clarification

 

[lini]

Hey Lini! Another VE peep here. (...)

Oops, almost forgot to reply: Nice to see you here, too!

Anyway, unfortunately I haven't got any personal experience with these two newer DJ/broadcast Concorde family models - and also not with the Fosi X5. But the output level specs from Ortofon would appear pretty plausible - and considering Amir's test results of the Fosi, it might have some difficulties with such hot DJ/broadcast carts in combination with very hot cuts, so that among the priceworthy phono stage models the Schiit Mani 2, run in its lowest gain setting (alias Decca mode), could be a better choice.

Greetings from Munich!

Manfred / lini

 

[Muddywaters]

Oops, almost forgot to reply: Nice to see you here, too!

Anyway, unfortunately I haven't got any personal experience with these two newer DJ/broadcast Concorde family models - and also not with the Fosi X5. But the output level specs from Ortofon would appear pretty plausible - and considering Amir's test results of the Fosi, it might have some difficulties with such hot DJ/broadcast carts in combination with very hot cuts, so that among the priceworthy phono stage models the Schiit Mani 2, run in its lowest gain setting (alias Decca mode), could be a better choice.

Greetings from Munich!

Manfred / lini

Glad to see you around here too lini!

Greetings from Naples (Fl)

*edit for context

 

[Ropeburn]

Very nice quality, and cheap too! What I really like is the high gain settings independent of MM/MC setting. You could even directly drive a poweramp with this, an MM cartridge, and a simple passive attenuator.

 

[raulillo88]

After reading a lot of good experiences with this preamp and because my amp sometimes in phono stage began to make awful noises in left channel I bought this Fosi. I was very excited because everybody says it sounds pretty good, but when I connected to my turntable with an Audio-Technica vm95ml my expectations have gone to the floor. Sounds pretty awful. I don't know if it just me but sounds like a boom box. Music sounds pretty bassy and without any quality. I have tried connecting again to my amp directly and sounds so much better. Maybe this preamp only worthwhile for MM cartridges or maybe is faulty. Have anyone had same experience?

 

[Miser_Audioman]

After reading a lot of good experiences with this preamp and because my amp sometimes in phono stage began to make awful noises in left channel I bought this Fosi. I was very excited because everybody says it sounds pretty good, but when I connected to my turntable with an Audio-Technica vm95ml my expectations have gone to the floor. Sounds pretty awful. I don't know if it just me but sounds like a boom box. Music sounds pretty bassy and without any quality. I have tried connecting again to my amp directly and sounds so much better. Maybe this preamp only worthwhile for MM cartridges or maybe is faulty. Have anyone had same experience?

Hi, vm95 is a moving magnet. Make sure you are using the MM setting in the back. It will sound terrible on the MC setting. Hope this helps..

 

[raulillo88]

Hi, vm95 is a moving magnet. Make sure you are using the MM setting in the back. It will sound terrible on the MC setting. Hope this helps..

I'm feeling stupid. That was the problem

Now sounds pretty good a little clearer than my Sony TA-1140 internal phono.
For this price is a very good purchase and I highly recommend it

 

[Miser_Audioman]

I'm feeling stupid. That was the problem

Now sounds pretty good a little clearer than my Sony TA-1140 internal phono.
For this price is a very good purchase and I highly recommend it

Glad to help! No worries enjoy!

 

[antcollinet]

I'm feeling stupid. That was the problem

We all do something similar sometime. Don't worry about it.