I've searched the forums and the 'net generally but can find no hobbyist input on the PP400 phono preamp. Well, I just gambled $20 on one and, to my surprise, it's not horrible. Noise is low, detail is OK, and output is not as overly hot as I'd been led to believe. Channel separation / imaging seems a bit mediocre, and it does seem that it's lacking some oomph in the low registers.
Has anyone done any modding or experimentation with one of these?
Has anyone done any modding or experimentation with one of these?
Yeah, I've always thought I should be able to build a well-regarded pre for about $5-10 in parts. Over the last two years, such a plan has not come to my attention.
I bought the Behringer as a gamble to resolve an "emergency" left by the death of a beloved receiver in a room that sees 2-3 hours of vinyl time daily. But ultimately, $20 about is the cost of an enclosure, jacks, and a cheap power supply, plus shipping... and since I have Amazon Prime, I didn't even need to pay the latter on the PP400.
And if a replacement cap value or two has been discovered that would improve its abilities vastly... well, I just thought it was reasonable to ask
I bought the Behringer as a gamble to resolve an "emergency" left by the death of a beloved receiver in a room that sees 2-3 hours of vinyl time daily. But ultimately, $20 about is the cost of an enclosure, jacks, and a cheap power supply, plus shipping... and since I have Amazon Prime, I didn't even need to pay the latter on the PP400.
And if a replacement cap value or two has been discovered that would improve its abilities vastly... well, I just thought it was reasonable to ask
Hello all, I had a go with this thingy and looking at its PCB, its basic single chip dual opamp implementation, as basic and good as its price point. No audiophile caps of any sort. There isn't any input load shunt nor capacitance to match the cartridge loading. A little mod here may do some good. The opamp is smd, the wall wart is cheap skate, unless you can swap it for something better, there may be some hope. In stock form,don't expect stellar performance with this. Its cheap and useable, nothing more.
Hello,
I bought the Behringer PP400 just to compare it to a WBE DIAMOND No.36 STUDIO Phono Preamp which I own for my Rega 3 with Goldring 1042.
Complete hifi chain is: amplifiers are WBE Essence No.300, preamp is Adcom GFP-555II, loudspeakers are Pfleid FRS20S with modified PP100 (point source fullrange loudspeaker with integrated subwoofer).
So the PP400 from the scratch (costs 30 dollars) is a pretty thin and faint sounding device. From the theory there should be no audible difference between audio op-amps. So both phono preamps should sound quite similar. But it is far from that.
The WBE Phono preamp has an OPA627 (driven into class a) and sounds superb, and has a regulated power supply. The Behringer has a V4580 op amp from cool audio and no regulated supply.
The Behringer PP400 got better with an added 12v regulator 7812 and 15 Volt power supply source (2A).
Then I added to the opamp a 2,2mfd electrolyic across + and -, the sound got a little more body, clearly audible.
At last I changed two 4,7mfd electrolytics against WIMA MKS, C11 and C12. This helped a lot against the lack of body in sound and bass, now it got hifi quality.
There are some more electrolytics to change against better types in the Behringer PP400 but desoldering is a bit difficult because with the original solder used in this device so I stopped my modding and listening marathon.
Result: the biggest differences in sound are not from the op amp but everything around it. Could be that at last the OPA627 makes a difference but it was a nice test for me.
collection of websites on the pp400:
De Beterhringer PP-400 phono-pre – The sweet spot
PP400｜Tamesuke-Goto Maker的Blog
http://cdn2.bhphotovideo.com/lit_files/84924.pdf
https://www.hobbielektronika.hu/forum/getfile.php?id=110260
Bought a cheap preamp to play with... - Bry - Vinyl Asylum
Yours, Dragan from Germany
I bought the Behringer PP400 just to compare it to a WBE DIAMOND No.36 STUDIO Phono Preamp which I own for my Rega 3 with Goldring 1042.
Complete hifi chain is: amplifiers are WBE Essence No.300, preamp is Adcom GFP-555II, loudspeakers are Pfleid FRS20S with modified PP100 (point source fullrange loudspeaker with integrated subwoofer).
So the PP400 from the scratch (costs 30 dollars) is a pretty thin and faint sounding device. From the theory there should be no audible difference between audio op-amps. So both phono preamps should sound quite similar. But it is far from that.
The WBE Phono preamp has an OPA627 (driven into class a) and sounds superb, and has a regulated power supply. The Behringer has a V4580 op amp from cool audio and no regulated supply.
The Behringer PP400 got better with an added 12v regulator 7812 and 15 Volt power supply source (2A).
Then I added to the opamp a 2,2mfd electrolyic across + and -, the sound got a little more body, clearly audible.
At last I changed two 4,7mfd electrolytics against WIMA MKS, C11 and C12. This helped a lot against the lack of body in sound and bass, now it got hifi quality.
There are some more electrolytics to change against better types in the Behringer PP400 but desoldering is a bit difficult because with the original solder used in this device so I stopped my modding and listening marathon.
Result: the biggest differences in sound are not from the op amp but everything around it. Could be that at last the OPA627 makes a difference but it was a nice test for me.
collection of websites on the pp400:
De Beterhringer PP-400 phono-pre – The sweet spot
PP400｜Tamesuke-Goto Maker的Blog
http://cdn2.bhphotovideo.com/lit_files/84924.pdf
https://www.hobbielektronika.hu/forum/getfile.php?id=110260
Bought a cheap preamp to play with... - Bry - Vinyl Asylum
Yours, Dragan from Germany
Hello,
I tried to short the input and output coupling elecrolytics c1 to c4 with a wire as desoldering and changing against other types is difficult - this is no good idea. DC is coming through, no output.
I changed the 2,2 mfd across VCC(+) and VEE(-) to 22mfd with a Panasonic FC-type.
Now the sound became more analytic and much more substantial in the bass. Now the Behringer PP400 sounds with full power in the bass. I did not expect that. Lossy types of electrolytics certainly sound nicer here than the Low-ESR-Panasonic.
Result: op amps sound quite different only by changing the decoupling, the influence in sound is huge. I wonder if this could be measured. By listening the difference is quite obvious.
Subjectively the difference in sound between the original Behringer PP400 and the modded one with decoupled op amp is 10db in the bass. This is really a huge difference(!)
http://3.bp.blogspot.com/-GYyVTGU9x6M/UA2YRmar0zI/AAAAAAAAAp0/tFdWx4UJsG0/s1600/20120723_004.jpg
Bye, Dragan
I tried to short the input and output coupling elecrolytics c1 to c4 with a wire as desoldering and changing against other types is difficult - this is no good idea. DC is coming through, no output.
I changed the 2,2 mfd across VCC(+) and VEE(-) to 22mfd with a Panasonic FC-type.
Now the sound became more analytic and much more substantial in the bass. Now the Behringer PP400 sounds with full power in the bass. I did not expect that. Lossy types of electrolytics certainly sound nicer here than the Low-ESR-Panasonic.
Result: op amps sound quite different only by changing the decoupling, the influence in sound is huge. I wonder if this could be measured. By listening the difference is quite obvious.
Subjectively the difference in sound between the original Behringer PP400 and the modded one with decoupled op amp is 10db in the bass. This is really a huge difference(!)
http://3.bp.blogspot.com/-GYyVTGU9x6M/UA2YRmar0zI/AAAAAAAAAp0/tFdWx4UJsG0/s1600/20120723_004.jpg
Bye, Dragan
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Ah, Tamesuke has on his Blog a schematic of the Behringer PP400. And a jpg of a modded Behringer ;-)
PP400の画像 | Tamesuke-Goto Maker的Blog
PP400の画像 | Tamesuke-Goto Maker的Blog
Hi all, nice to see this revived since 2010.
The PP400 is among the simplest phono I've seen for USD20 at that time. 7 years have past and the price is now inflated to near double where I reside. Even the landed cost of the Schiit Mani isn't exactly the cheapest solution to those wanting their 1st phono stage. I've seen and heard the Schitt (maybe this PP400 too) improve with use of bigger aftermarket upgrade PSU transformer box. Both don't have capacitance loadings at input, open to modders to add any to their liking.
The PP400 is among the simplest phono I've seen for USD20 at that time. 7 years have past and the price is now inflated to near double where I reside. Even the landed cost of the Schiit Mani isn't exactly the cheapest solution to those wanting their 1st phono stage. I've seen and heard the Schitt (maybe this PP400 too) improve with use of bigger aftermarket upgrade PSU transformer box. Both don't have capacitance loadings at input, open to modders to add any to their liking.
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@coolmaster
yeah, the consequence from my experiments of tuning the Behringer PP400 is that it makes completely sense for me to buy another PP400 and design its sonic signature to my taste. (For example sweet midrange but controlled with a slight roll - off in the bass, that is _my_ taste.)
I was astonished to recognize that the decoupling of the op amp has such a big influence on sound.
I guess what makes the difference: if you measure the op amp you possibly cannot find any difference in frequency response at all but if the op amp has to deliver current - the lack of any decoupling could make it sound thin and faint without real "oomph" in the bass as someone described it.
This explains to me the big difference in sound I experienced when I was listening two DACs for my CD-Player in the 3000 Euro region. The sound was completely different - one DAC sounded very bassy and the other one thin and fast. Subjectively the sound difference in the bass was 15db, absolutely incredible. As a result I did not buy any expensive hifi gear any more because I was irritated.
Because of the different sound of loudspeakers I began to build my own ones - strictly to scientific knowledge.
Bye, Dragan
yeah, the consequence from my experiments of tuning the Behringer PP400 is that it makes completely sense for me to buy another PP400 and design its sonic signature to my taste. (For example sweet midrange but controlled with a slight roll - off in the bass, that is _my_ taste.)
I was astonished to recognize that the decoupling of the op amp has such a big influence on sound.
I guess what makes the difference: if you measure the op amp you possibly cannot find any difference in frequency response at all but if the op amp has to deliver current - the lack of any decoupling could make it sound thin and faint without real "oomph" in the bass as someone described it.
This explains to me the big difference in sound I experienced when I was listening two DACs for my CD-Player in the 3000 Euro region. The sound was completely different - one DAC sounded very bassy and the other one thin and fast. Subjectively the sound difference in the bass was 15db, absolutely incredible. As a result I did not buy any expensive hifi gear any more because I was irritated.
Because of the different sound of loudspeakers I began to build my own ones - strictly to scientific knowledge.
Bye, Dragan
@coolmaster
yeah I swapped in many Tuners, Amplifiers and CD-Players the opamps. But there is a lot of critique on "op-amp rolling" without considering the design of the circuit.
I think many hifi gear was not developed with much care because there are so many bad sounding coupling electrolytics in signal paths and unregulated power supplies out there that I do not believe in the words that the technicians did know what they did when designing a circuit.
So I do concentrate on the power supply - very often also in expensive gear - the power-supply regulators 78xx and 79xx are not wired to the recommended capacitors what is clearly described in the datasheet.
What I could not imagine is the huge difference in sound generated by a good decoupling of the op-amp!
Now why are there any differences in the estimation of the sound at all?
Loudspeakers can sound in the bass region very different in different rooms with amplitude variations of up to 30db(!) Depending on the resonances, low-frequency response of the speaker and space in the room. This is the situation not only at private homes but also in test rooms of sound studios.
yeah I swapped in many Tuners, Amplifiers and CD-Players the opamps. But there is a lot of critique on "op-amp rolling" without considering the design of the circuit.
I think many hifi gear was not developed with much care because there are so many bad sounding coupling electrolytics in signal paths and unregulated power supplies out there that I do not believe in the words that the technicians did know what they did when designing a circuit.
So I do concentrate on the power supply - very often also in expensive gear - the power-supply regulators 78xx and 79xx are not wired to the recommended capacitors what is clearly described in the datasheet.
What I could not imagine is the huge difference in sound generated by a good decoupling of the op-amp!
Now why are there any differences in the estimation of the sound at all?
Loudspeakers can sound in the bass region very different in different rooms with amplitude variations of up to 30db(!) Depending on the resonances, low-frequency response of the speaker and space in the room. This is the situation not only at private homes but also in test rooms of sound studios.
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this phono amp under
The Dismantler: Behringer Microphono PP400 phono preamp
is similar to the Vivanco PA111 - go to
VIVANCO PA-111 PHONO-VORVERSTÄRKER, Analogtechnik/Plattenspieler - HIFI-FORUM
- also a cheap device for tweacking.
Most important is the power supply.
also great influence will have the capacitors in the signal path and the operational amplifier IC.
There are also a version with volume control - go to
DE Ultra-compact Phono Preamp Preamplifier with Level & Volume Controls RCA K0P8 | eBay
Interesting ICs for replace are AD826, ADA4898-2, AD8066 or THS4032.
This types I will test next time.
The Dismantler: Behringer Microphono PP400 phono preamp
is similar to the Vivanco PA111 - go to
VIVANCO PA-111 PHONO-VORVERSTÄRKER, Analogtechnik/Plattenspieler - HIFI-FORUM
- also a cheap device for tweacking.
Most important is the power supply.
also great influence will have the capacitors in the signal path and the operational amplifier IC.
There are also a version with volume control - go to
DE Ultra-compact Phono Preamp Preamplifier with Level & Volume Controls RCA K0P8 | eBay
Interesting ICs for replace are AD826, ADA4898-2, AD8066 or THS4032.
This types I will test next time.
Attachments
Just looking for a cheap phono amp and I found this YouTube video on the pp400 with some measurements, circuit diagram and simple mods which flatten the frequency response and increase the gain. Worth a look N-Audio PP400 Phono Preamp Modifications [Re-Upload] - YouTube