Topping Pre90 Review (preamplifier)

[nagster]

It's not only correct, it is required.

Sorry if I'm wrong. I'm not good at English so it's Google Translate.

 

[nagster]

AP dashboard and 32 tone of the Pre90 XLR output connected to the SE input.

 

[Sokel]

AP dashboard and 32 tone of the Pre90 XLR output connected to the SE input.

Balanced to SE connections with pin 3 (cold) either open or connected to ground (pin 1) is a horror show,probably that's what Topping has seen and (rightfully) suggests not to do it.
Nice demonstration!

 

[CleanSound]

Because they couldn't fit everything into one chassis, they have to have a extension chassis. God, I hate desktop form factors, it's like a little child's toy.

 

[nagster]

It looks a little better compared to D10 Balanced. Of course, neither result is recommended.
However, in the case of Pre90, the offset does not seem to worsen, so pin 3 open may be used only in emergencies.

Topping D10 Balanced Review (USB DAC)

It looks (in my case) ,that the onboard switching power supply + 5.65V / -5.6V, which supplies the output analog circuits (3 OA) behind the DAC, fails / does not start ..). That PSU is powered from 5V inputs. The all other onboard sources (3.3V, 1.2V, 1V) start up normally, they are linear (not...

www.audiosciencereview.com

 

[maudio]

I have a problem with Topping RCA in / XLR Out -> Amp XLR in. As opposed to pure RCA signal path, this sound is somehow weak, dynamically constricted, sounds like a a bad copy on cassette from 80s.

Does Pre90 convert the RCA in into a full blown XLR signal, or just pass it somehow trough?
My amp has also RCA in and this way the sound is great, but wanted to get those 3dB better signal and what i got is i dunno 20 dB worse

So it can be 2 things: my Amp XLR in is screwed OR
Pre90 does not really convert RCA in into full scale XLR out.

If the latter case, was i too naive expecting it would do it? I had 2 preamps that did this and it was no problem, RCA in XLR out. They costed also more.

 

[ZestClub]

I have a problem with Topping RCA in / XLR Out -> Amp XLR in. As opposed to pure RCA signal path, this sound is somehow weak, dynamically constricted, sounds like a a bad copy on cassette from 80s.

Does Pre90 convert the RCA in into a full blown XLR signal, or just pass it somehow trough?
My amp has also RCA in and this way the sound is great, but wanted to get those 3dB better signal and what i got is i dunno 20 dB worse

So it can be 2 things: my Amp XLR in is screwed OR
Pre90 does not really convert RCA in into full scale XLR out.

If the latter case, was i too naive expecting it would do it? I had 2 preamps that did this and it was no problem, RCA in XLR out. They costed also more.

It can't convert RCA to balanced that's not how it works.
You need balance all the way down the chain from the source player/ streamer to the Pre amp and then onto the main amps.
A player may have a balanced 4.4mm jack or XLR's - but if its just phono then you need to stay with that all the way down the chain.
Only option is to upgrade the source latter.

 

[Jimbob54]

It can't convert RCA to balanced that's not how it works.
You need balance all the way down the chain from the source player/ streamer to the Pre amp and then onto the main amps.
A player may have a balanced 4.4mm jack or XLR's - but if its just phono then you need to stay with that all the way down the chain.
Only option is to upgrade the source latter.

Forget the word balanced and focus on just input and outputs. You absolutely can input an RCA source into the Pre90 and it can be output via the XLR outputs. Other than output level (I assume XLR out should always be 6dB more than RCA out) they should sound the same. That isnt what @maudio is reporting.

I assume @maudio has selected the right input and output options via the dials/ remote. Something is definitely wrong if the output level out of the XLRs is noticeably less than the RCA out. Checked all your connections? If you have both RCA and XLR out connected to the same amp is there a noticeable drop in level at the same volume level on the Pre 90 when you switch from RCA out to XLR out (and obviously select the relevant input on the power amp? I would test this at quite low levels in case you get a big jump from one to the other. What level on the Pre90 do you need to use for RCA out and XLR out to get the same perceived volume out of the speakers .I would have thought like you that the XLR output should be higher so you would turn that down compared to RCA output.

What is the poweramp by the way?

 

[mocenigo]

It can't convert RCA to balanced that's not how it works.

Oh yes it does.

 

[rvsixer]

It can't convert RCA to balanced that's not how it works.
You need balance all the way down the chain from the source player/ streamer to the Pre amp and then onto the main amps.
A player may have a balanced 4.4mm jack or XLR's - but if its just phono then you need to stay with that all the way down the chain.
Only option is to upgrade the source latter.

Per the user manual it does convert SE to XLR, and vice versa. It even goes so far as to give very detailed audio measurements of each of the four possible input->output scenarios (including voltage in and voltage out for each).

 

[ZestClub]

Just because they say it can work that way doesn't mean that it does.
I have one and never got it to work that way - same problem as the OP.
Mine always works balanced all the way through from the player in Pre=>Low mode balanced output via a 4.4mm jack.

 

[iLoveCats]

I run a phono preamp in rca and out xlr to the amp and I have to turn the Pre 90 way up when I switch to rca input. I don't think it sounds bad though, just the gain is off compared to xlr input.

 

[Dgob]

Oh yes it does.

Absolutely. This is just a fact.

 

[Jimbob54]

I run a phono preamp in rca and out xlr to the amp and I have to turn the Pre 90 way up when I switch to rca input. I don't think it sounds bad though, just the gain is off compared to xlr input.

Well yes, its presumably half the voltage all other things being equal. A 6dB difference which would have to be countered by upping the volume on the Pre 90 output.

But thats diifferent to the poster saying XLR out was quieter / different to RCA out from teh same RCA source. That aint right!

 

[Jimbob54]

Just because they say it can work that way doesn't mean that it does.
I have one and never got it to work that way - same problem as the OP.
Mine always works balanced all the way through from the player in Pre=>Low mode balanced output via a 4.4mm jack.

Topping Pre90 Review (preamplifier)

Any single-ended to balanced conversion (or vice-a-versa) like with the Schiit Freya S (discontinued)? I suspect not, but just asking. [This is an additional post from an edit of my previous post; deleted it from there and split it off to this new post]

www.audiosciencereview.com

Then either something was broken in your chain or user error. But it definitely should work. Also, how did you convert XLR to 4.4mm?

 

[ZestClub]

Topping Pre90 Review (preamplifier)

Any single-ended to balanced conversion (or vice-a-versa) like with the Schiit Freya S (discontinued)? I suspect not, but just asking. [This is an additional post from an edit of my previous post; deleted it from there and split it off to this new post]

www.audiosciencereview.com

Them either something was broken in your chain or user error. But it definitely should work. Also, how did you convert XLR to 4.4mm?

Doesn't work properly.
I connect using a set of IFi leads (4.4mm jack to twin XLRs).

 

[Jimbob54]

Doesn't work properly.
I connect using a set of IFi leads (4.4mm jack to twin XLRs).

So I stand by what I said in that post. Either something was broken or user error. Pretty sure if the p90 was broken by design (low output from xlr compared to rca using same rca source) this would have been uncovered by now. It's just a shame amir didn't test rca in to xlr out. But maybe someone has. With a 2v rca signal in, set to 0db, I would expect 4v out of xlr

 

[Rhamnetin]

Just because they say it can work that way doesn't mean that it does.
I have one and never got it to work that way - same problem as the OP.
Mine always works balanced all the way through from the player in Pre=>Low mode balanced output via a 4.4mm jack.

I've done SE input -> balanced output on my Pre90 without issue. Granted I just tested this by ear, and observed none of the issues described previously.

 

[rvsixer]

It's just a shame amir didn't test rca in to xlr out. But maybe someone has. With a 2v rca signal in, set to 0db, I would expect 4v out of xlr

Topping has already tested this (as mentioned in my previous post).

I'm not sure why all the Topping product spec/test result doubt here. Topping is NOT known for bogus product specs, or publishing bogus in-house Audio Precision test results (as Amir's testing repeatedly bears out). So I'd still go with/believe the SE-BAL product spec/test results they have published.

 

[Jimbob54]

Topping has already tested this (as mentioned in my previous post).

I'm not sure why all the Topping product spec/test result doubt here. Topping is NOT known for bogus product specs, or publishing bogus in-house Audio Precision test results (as Amir's testing repeatedly bears out). So I'd still go with/believe the SE-BAL product spec/test results they have published.

As would I. I'm not the one saying it doesn't work.