Topping Pre90 Review (preamplifier)

[Tigi]

OK, but most external DACS can also can control the volume and provide a proper load. What would be the point of this product if you only have digital sources?

This preamp could be a suitable solution also for those who have only one digital source (CD player or DAC), which either does not have volume control or has a volume control, but for some reason it is not preferred by the user. Some people still consider digital volume control in the DAC to be inferior and prefer a traditional separate analog preamp.

 

[restorer-john]

As a sincerity test the pre should be measured into the same impedance as it itself presents. This could go either way, but what is good for the goose is good for the gander as they say.
It would be most embarrassing if it could not sustain the performance into a low Z load. Trivially just cascade one channel into the other and see how it does.

I don't agree. Most 'normal' HiFi preamplifiers present 47-50K input impedance on line inputs (same as a MM input), so they would also get a free pass when it came to output drive capability and THD into a 'typical' lowish impedance power amp in the 'cascade' situation. I have power amps ranging from 20-25K at the low end to >50K at the high end. But modern 'numbers game' power amps have abandoned the FET front ends and gone for ultra low input impedances. This should be considered.

I would pick a nominal lowish impedance load (either worst case 2K, or say 10K as a reasonable figure) and use that as a standard for THD vs level or THD vs Frequency (like what is done for power amps and headphone amps).

There must however be a common figure and 200K is not the load to be used. A preamplifier is, after all, an amplifier, and no amplifier should be tested in an essentially unloaded situation and any conclusions drawn as to its real world performance.

 

[ABall]

I have been looking for a preamp that 1, I can afford and 2, is transparent, and it has to have a minimum of 4 inputs. I thought this was it but all those balanced inputs????? Am I in the minority? None of my source components are balanced, I have an AV amp that uses my Monoblocks for front left/right, a 1990 CD player, a record deck, a bluetooth receiver and a squeezebox touch. I thank @restorer-john for his opinion and comments here, I have now crossed this off my christmas list.....

 

[restorer-john]

Am I in the minority?

No, you are certainly not in the minority. That said, the further you go up in product ranges, the more XLRs you may get, but certainly not at the expense of the de-facto connection, the RCA.

Here's a TOTL Yamaha AS-3000/CDS-3000 pair. Plenty of RCAs to be seen here.

Here's a TOTL Accuphase preamplifer, the C-2850

Here's the new C-3900 Accuphase. More XLRs, but still plenty of RCAs for unbal.

I would liked to see the Topping switcher have at least another pair of XLRs and say six pairs of RCAs instead of the configuration it has.

 

[win]

This preamp could be a suitable solution also for those who have only one digital source (CD player or DAC), which either does not have volume control or has a volume control, but for some reason it is not preferred by the user. Some people still consider digital volume control in the DAC to be inferior and prefer a traditional separate analog preamp.

These days that is how I use my analog preamp. I do sometimes use the tube mode, but often I am actually using an extraneous da/ad conversion to achieve this just this. I actually jump from a dac to an analog preamp and then back into my crossover which has an adc.

The clicky volume control gives feedback that would otherwise be missed and probably blow my speakers up. Also allows for a knob that actually feels like something, not just a hollow, gummy piece of plastic.

I also have Lutron pico remotes around the house that control this same volume, so again the clicky feedback is something I have a use for.

 

[Francis Vaughan]

There must however be a common figure and 200K is not the load to be used. A preamplifier is, after all, an amplifier, and no amplifier should be tested in an essentially unloaded situation and any conclusions drawn as to its real world performance.

I quite agree. I was making a different point, basically that if Topping presents 2k they minimally must be able to drive it, simply as test of their engineering sincerity. Loading of line level output is a good question for testing. Hopefully it doesn’t affect most modern equipment much. But the woo end of town is renowned for stupid engineering choices and it would not surprise me that some could be found wanting. Especially as it leaves the door open for cable capacitance to act as a tone control.

 

[ABall]

No, you are certainly not in the minority. That said, the further you go up in product ranges, the more XLRs you may get, but certainly not at the expense of the de-facto connection, the RCA.

Here's a TOTL Yamaha AS-3000/CDS-3000 pair. Plenty of RCAs to be seen here.
View attachment 99094

Here's a TOTL Accuphase preamplifer, the C-2850
View attachment 99095

Here's the new C-3900 Accuphase. More XLRs, but still plenty of RCAs for unbal.

View attachment 99097

I would liked to see the Topping switcher have at least another pair of XLRs and say six pairs of RCAs instead of the configuration it has.

How about something under £1000 that's totally transparent and has remote volume/input switching?

 

[win]

How about something under £1000 that's totally transparent and has remote volume/input switching?

Freya fits the bill for this. No direct input selection, but can cycle through (5). Passive mode is as transparent as the apx555 can measure, practically.

 

[amirm]

Freya fits the bill for this. No direct input selection, but can cycle through (5). Passive mode is as transparent as the apx555 can measure, practically.

That also means its impedance is variable and volume dependent.

 

[Mikechw]

https://www.mola-mola.nl/makua.php

Well this one has good specs, input impedance is normal, dual balanced output for bi-amp, remote controlled.
But price is out of range..

 

[PeteL]

That also means its impedance is variable and volume dependent.

Yes, and also that it won't convert an unbalanced input to balanced in this mode. In real life the numbers on the actual "preamp" modes of the Freya are arguably close enough, but more useful for most. IMO.

 

[m8o]

Anyone know if this has a balanced/symmetric circuitry from input to output when one uses a balanced input? Or is it just the boring old balanced in to a differential in of an opamp to a single-ended circuit to an inverter @ the output to make balanced out?

 

[Rottmannash]

No, you are certainly not in the minority. That said, the further you go up in product ranges, the more XLRs you may get, but certainly not at the expense of the de-facto connection, the RCA.

Here's a TOTL Yamaha AS-3000/CDS-3000 pair. Plenty of RCAs to be seen here.
View attachment 99094

Here's a TOTL Accuphase preamplifer, the C-2850
View attachment 99095

Here's the new C-3900 Accuphase. More XLRs, but still plenty of RCAs for unbal.

View attachment 99097

I would liked to see the Topping switcher have at least another pair of XLRs and say six pairs of RCAs instead of the configuration it has.

Preamp porn indeed

 

[ABall]

Freya fits the bill for this. No direct input selection, but can cycle through (5). Passive mode is as transparent as the apx555 can measure, practically.

Thanks but I'm looking for something active, I have an LDR tagged onto a DCB1 atm.

 

[PeteL]

Thanks but I'm looking for something active, I have an LDR tagged onto a DCB1 atm.

The Freya is good as an active preamp. They discontinued the S (solid state)version tough, The Freya + is a tube preamp but also has a JFET and a fully passive mode. The JFET stage has a THD+N of 0.004%, so, good, but not as good as the Topping on this metric. It has an input impedance of 10kohms. The Topping I've read in this thread 2k, but I don't see it specified clearly, so depending of your need the Freya may be an option in the sub 1k$ category. I'm satisfied with mine, for what it's worth.

 

[misterdog]

the de-facto connection, the RCA.

Though some of us would prefer to do away with any RCA plugs, where the live pin contacts first (POP) and no separate ground (BUZZ).

The old days were good, but progress has some benefits.

For those who insist on these features though the Mola Mola Makua fits the bill at the price of £ 6,000-00..
Though some 'purists' would baulk at this.

All stages in the Makua use discrete amplifier modules in a little known topology called "single-ended driven differential"

Claiming that additional components used in balanced equipment degrades SQ, and ignore this.

Distortion at maximum signal level (THD, IMD): not measurable, estimated around -150dB

I use a Bruno Putzeys designed DIY pre which only has XLR connectors, my phono stage works fine through it.. It is a very simple process to fit XLR plugs, or balanced cable to legacy equipment.
Why people see it as like trying to operate 110V equipment at 230V I have no idea.

 

[AndyLu]

I have been looking for a preamp that 1, I can afford and 2, is transparent, and it has to have a minimum of 4 inputs. I thought this was it but all those balanced inputs????? Am I in the minority? None of my source components are balanced, I have an AV amp that uses my Monoblocks for front left/right, a 1990 CD player, a record deck, a bluetooth receiver and a squeezebox touch. I thank @restorer-john for his opinion and comments here, I have now crossed this off my christmas list.....

 

[bungle]

View attachment 99202

That I nice, but these inputs found in RME are even nicer. XLR and Jack in single input (very common in pro-audio).

 

[aHaidc]

This one looks promising but I would wait for the 'tube' preamp that @JohnYang1997 has mentioned before I would like to have some 'noise' and 'distortion' on my system. It would be great if have the both SS and Tube mode on that (giant killer?) preamp. BTW, is this an analog preamp?

 

[restorer-john]

Though some of us would prefer to do away with any RCA plugs, where the live pin contacts first (POP) and no separate ground (BUZZ).

Seriously, who on this planet hot swaps or connects anything to a power amplifier when it is turned on with the gain pots wide open?

I say to those people, they deserve what they get.