Measurements of Gustard P26 Preamplifier

[alexbilchuk]

Superb and very usable insights .
How is the P26 remote .Does it move smoothly?
My setup denon DNP to Ares2 to Pa5. I need remote so planning for P26 inbetween ares2 and pa5

P26 remote working without problem in my setup, but I'm sitting 1.5 m from amp. I will try how it works on longer distances and report about.

 

[alexbilchuk]

P26 remote working without problem in my setup, but I'm sitting 1.5 m from amp. I will try how it works on longer distances and report about.

Remote works flawlessly at my listening position (2 meters at front) and from 3 meters right side at 45 degree, but from the left not so good, only 20 or so degree. I think it works nice in general.
You can use it in step by step mode by short press (100 steps, never used more then 80 using rca-xlr, max 50-60 using xlr-xlr) and in quick mode by long press (rarely using this mode). Yes, from 2 meters you can hear clicking of relays, but it doesn't bother me because it sounds very subtle, anyway you should listen to music, not relays)))

 

[DBB]

@WolfX-700

Can you tell me how you opened the case of the P26?

I bought a Gustard p26 preamp and am considering a plan to swap op amps. The problem is, after removing a few screws that appeared to be securing the top, it won't budge. I assumed the top aluminum plate is snapped in, but I see no way of getting a tool in to pop it out. I don't want to scratch it up by forcing a knife or screwdriver in. Is there a trick to this? Help.

The solution might be a slide out after taking off the front knob. I took off the front knob, and some remaining back screws and couldn't slide it. I then started taking out screws from the bottom, but changed my mind. Too many screws. I didn't want to accidentally loosen something important on the board. It is a fine sounding preamp. I don't want to break it.

 

[nn_in]

More than a month ago, an old friend asked me, would you measure a Gustard P26 preamp?In fact, I didn't know Gustard was going to launch this product until he asked me.I then contacted Gustard, who said at the time that P26 had not been officially completed. After the official release, I will send me a retail version for measurement.

Just a few days ago @Max Also ask me if I will measure this unit?In fact P26 was on the road the next day.

Today I got the P26, and the measurement took me a lot of time. Because the preamplifier is very different from the DAC, there is basically no SOP at all. If there are any shortcomings in the following measurements, if you want to know something else, please let me know.

Look at things first:

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Actually I always wanted a decent preamp

In fact, I always wanted a decent preamp, but the tragic fact is that it is almost full of garbage (maybe I didn't find it) under $ 1,000. It is not just a defect in the measurement data, but a question of completion.

What I mean by completeness refers to the appearance, function (input and output interface), operation friendliness, function implementation results (such as noise when switching volume), and even the ability to clearly show what you want What you know (input, output, volume, etc.)

This even forced me to do a preamp to achieve what I wanted.But although I realized most of what I wanted, it still couldn't satisfy me. Because the interior is composed of various small modules, and some modules are purchased (such as input and output switching and display), it cannot be said to be a "finished product" at all, but only a "usable" thing
And the cost of making it is close to $ 1,000 (not including the time I spent!!)

And Gustard's long-term adherence to the discrete voltage amplifier circuit has made me have a little more expectations for the sound of this preamp.

Well, don't talk nonsense. Measure it!

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Update: Left channel PS Noise issue has been fixed and the manufacturer has been notified of the fix. Since repairs do not require costs, manufacturers will immediately produce to new standards. :
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We can see that there seem to be two sets of very different input stages. One is responsible for the input of the balanced signal, and the other is responsible for the input of the unbalanced signal.

In fact, I also got this information from the developer, and the circuit of unbalanced input will also be used for "input gain + 6db setting". This means that the input gain +6 will also affect some basic measurement results in the same way as above.
Fortunately, we generally do not need a large input gain. And if you really feel that the sound is too low (this preamp is actually close to 0db gain by default) you can start "output gain +6" Settings ---- This function does not affect the basic measurement results.

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The following measurements were made at XLRin XLROut 4VRMS：

First and foremost: volume control:
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You can see that the volume control is very linear and the channel balance (green line) is very good. At the same time, the effect of volume adjustment on SINAD is minimal. The disadvantage is that the limit value of the volume control (-60db)may not be low enough in some cases.

Output impedance:
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THD+N Vs Freq：

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All of the above, I think for a preamp of less than $ 700, it is very, very, very good.

I've measured DACs from Gustard before, and to be honest, I'm a little disappointed-let's say the A22 finally achieved the result with double 4499.

I also said that Gustard's insistence on discrete output stages may be the main reason that affects the measurement results of their products.

But on this product today, I really have nothing to say.

A low-cost, high-performance, good-looking preamp. Sorry I have never met before.

What's past is prologue. The future can be expected.

Discrete Class A preamplifier - is this the output stage ?​

 

[DiegoV]

@WolfX-700

Can you tell me how you opened the case of the P26?

I bought a Gustard p26 preamp and am considering a plan to swap op amps. The problem is, after removing a few screws that appeared to be securing the top, it won't budge. I assumed the top aluminum plate is snapped in, but I see no way of getting a tool in to pop it out. I don't want to scratch it up by forcing a knife or screwdriver in. Is there a trick to this? Help.

The solution might be a slide out after taking off the front knob. I took off the front knob, and some remaining back screws and couldn't slide it. I then started taking out screws from the bottom, but changed my mind. Too many screws. I didn't want to accidentally loosen something important on the board. It is a fine sounding preamp. I don't want to break it.

Don’t bother, unless you have the 1st generation the op amps are Soldered in and no longer interchangeable. Per ShenzenAudio website:
“Because the DIP8 had been discontinued, the new batch LME49860 was changed to SO-8 version without op-amp socket.”

 

[DiegoV]

Speaking of the Gustard P26, mine just died yesterday. Won’t turn on, fuse blown, swapped out fuse, spare fuse went also. Just had it since July Hopefully this is under warranty repair.

 

[DBB]

@DiegoV
@WolfX-700 wolfx

I requested and ordered the model with the sockets.

Gustard responded to me by email:
"There are currently two versions. If you need an op amp socket version, please inform the merchant at the time of purchase."

Did you open the case?

 

[DiegoV]

@DiegoV
@WolfX-700 wolfx

I requested and ordered the model with the sockets.

Gustard responded to me by email:
"There are currently two versions. If you need an op amp socket version, please inform the merchant at the time of purchase."

Did you open the case?

Who do I email? Gustard or ShenzenAudio?

 

[DBB]

The retailer, shenzhenaudio. Gustard said both models are available. I therefore requested the model with sockets when I ordered it from Shenzhenaudio. However, I have not been able to open the case. Does anyone here know how to do that?

 

[LSB]

Does anyone here know how to do that?

Its best you do not open the case as you would almost certainly void your warranty. Although It just takes a screwdriver and two minutes to open it and no special tools or techniques are needed, this does not mean you should do it.

Speaking of the Gustard P26, mine just died yesterday.

Sorry to hear that. You are terribly unlucky. Was there flash or pop when it blew? Does it smell like burnt plastic from a short out?

 

[DBB]

Although It just takes a screwdriver and two minutes to open it and no special tools or techniques are need. . .

I removed screws at the back and underneath the case but the top didn't budge. I did not want to scratch it by prying it or forcing the top. After the screws were removed, the top remained tight in spite of my efforts to slide it back or up. Can you kindly state very specifically exactly how you got it off. ( I'm assuming you actually removed it, unless your post was based on speculation.) Thanks.

 

[nn_in]

Remote works flawlessly at my listening position (2 meters at front) and from 3 meters right side at 45 degree, but from the left not so good, only 20 or so degree. I think it works nice in general.
You can use it in step by step mode by short press (100 steps, never used more then 80 using rca-xlr, max 50-60 using xlr-xlr) and in quick mode by long press (rarely using this mode). Yes, from 2 meters you can hear clicking of relays, but it doesn't bother me because it sounds very subtle, anyway you should listen to music, not relays)))

The remote does not turn on/off the unit though...

 

[alexbilchuk]

The remote does not turn on/off the unit though...

Yes. remote doesn't power off preamp, but it's normal practice not to switch off audiogear everyday, especially preamps or dacs, if it not vacuum tube based.

 

[DBB]

@WolfX-700

Can you tell me how you opened the case of the P26?

I bought a Gustard p26 preamp and am considering a plan to swap op amps. The problem is, after removing a few screws that appeared to be securing the top, it won't budge. I assumed the top aluminum plate is snapped in, but I see no way of getting a tool in to pop it out. I don't want to scratch it up by forcing a knife or screwdriver in. Is there a trick to this? Help.

The solution might be a slide out after taking off the front knob. I took off the front knob, and some remaining back screws and couldn't slide it. I then started taking out screws from the bottom, but changed my mind. Too many screws. I didn't want to accidentally loosen something important on the board. It is a fine sounding preamp. I don't want to break it.

I know longer need help as I was able to open the case. My version, contrary to my request to the vendor, had surface mounted op amps so I could not do swapping. I returned the unit through Amazon.

 

[jlemaster1957]

Speaking of the Gustard P26, mine just died yesterday. Won’t turn on, fuse blown, swapped out fuse, spare fuse went also. Just had it since July Hopefully this is under warranty repair.

@DiegoV how is the warranty process working for you (given this occurred 2 weeks ago, it seems it may be underway- but important for those of us still contemplating doing business with the vendors to know.

 

[SoulsHarbor]

This is a good point. Are there other reasons for using a preamp now if one has a good DAC-power amp combination, with compatible voltage levels?

I keep seeing this question and I wonder why. What if you’re using other sources? A turntable, CD Player, RTR?

 

[SoulsHarbor]

Yes, but not for everyone. There is a (likely small) market for pieces like this.

What pre-amp at this price is balanced on both channels?

 

[kolestonin]

I had already decided to go with Topping Pre90 but then found a used Gustard P26 which will save me some money.
My quick research showed that it is a quality product with better remote control and higher input impedance than the pre90.
Measurements in this thread are also good so all in all it might be an equivalent or even a better option.

Do you think there can be any audible differences between the two preamps?

 

[wyup]

I know longer need help as I was able to open the case. My version, contrary to my request to the vendor, had surface mounted op amps so I could not do swapping. I returned the unit through Amazon.

Didn't you say earlier that you ordered and asked Shenzhenaudio for the op-amp mountable version? Why return to Amazon?
Does Shenzhenaudio ever sell through Amazon? See to believe it..

 

[galavoxx]

Didn't you say earlier that you ordered and asked Shenzhenaudio for the op-amp mountable version? Why return to Amazon?
Does Shenzhenaudio ever sell through Amazon? See to believe it..

Shenzen Audio sells these on Amazon as well. I am also trying to find out if they still offer swap-able op amps. @DBB were you able to confirm with Shenzen Audio even though you received the wrong one?