What's my boggle with phono preamps?

[adnick]

@lsipes1965 - I think I want a headamp for use with -low- output Grado carts, not high output.. I also have two different Ned Clayton SUTs, one of which may work well with a 1mV output - but like Grado told me, why put all that coil wire back in, when they removed it from the signal path for better clarity? I don’t know how nice the MP7 phono pre is, but their SU7 headamp may be just what I want..

Duane:


The issue with Grado’s “why put wire coils back” most MC carts use a SUT and some preform best with particular transformers.….even if your preamp has enough gain it‘s still an added device

VR
Andy

 

[MisterDK]

Duane:


The issue with Grado’s “why put wire coils back” most MC carts use a SUT and some preform best with particular transformers.….even if your preamp has enough gain it‘s still an added device

VR
Andy

I have an SUT that Ned made up for me to use with medium output MCs, like the Sumiko Blackbird that put out something like .8 or .9mV. It’s wired with two gain settings. The transformers are NOS, vintage Reichenbach BTW, probably before Cinemag took over. They look like Cinemag units. Gain was too low for the cartridge I ended up using and I never did buy a Blackbird.. Don’t really know how this one will sound - but may test it with a medium output Grado..

 

[wyn palmer]

”prefers” might be exaggerating If money was really tight, I’d rec the PyxiII(not in production) just because I could tell no real difference between the 2. And the PyxiII is more flexible. The 35db gain stage was more than adequate for higher output Grados. It’s a Gem. So is the MP7. I wanted to see what the 45db gain would do for a 1Mv out Grado I’ve got……not enough juice. Ned Clayton SUT came to fix that.

You'd need the Acrux, MC and MM separate inputs and 0-10dB in 2dB gain stepping, but I suspect that it's going to be way too expensive to justify relative to a SUT/MM input combo.
However, I am surprised that the 1mv sensitivity cartridge input is not sufficient. For 1mv cartridge sensitivity the max output of the Pyxi will be about 1mv x180x4=720mv. Most preamps can handle that as they have a gain of about 5 built in. In the MC mode the standard Pyxi will produce 7.2v!
It's hard to select a one input serves all approach when you only have two gain settings, alas.

 

[lsipes1965]

You'd need the Acrux, MC and MM separate inputs and 0-10dB in 2dB gain stepping, but I suspect that it's going to be way too expensive to justify relative to a SUT/MM input combo.
However, I am surprised that the 1mv sensitivity cartridge input is not sufficient. For 1mv cartridge sensitivity the max output of the Pyxi will be about 1mv x180x4=720mv. Most preamps can handle that as they have a gain of about 5 built in. In the MC mode the standard Pyxi will produce 7.2v!
It's hard to select a one input serves all approach when you only have two gain settings, alas

Wyn, it’s not that it won’t, it’s that to get to proper level it’s getting up into the noise floor of this Preamp I’ve got. Which intrudes too much for my taste. I’d love to try a Benchmark LA4/AHB2 combo one day,…

 

[Lavane]

I don't think anythings amiss, my system has always been dead quiet when using my DAC. My speakers are very efficient and I think the mostly tube preamps I've used have been the issue for me. Some people would be OK, I'm maybe just really picky.

I should say that that recently I did some testing between a Schiit Mani, U-Turn Pluto, and an 18 dollar Pyle PP999. The worst was the Schiit. The Pro-Ject I tried some years ago was tube.

Mike

I have a Pyle 999. I used it for a bit while working in another preamp. It's not horrible at all for what it is. I do plan on modding it just for fun. I read a thread on another sight where someone did some testing on the Pyle and a few other budget pbono preamps. The Pyle was quieter than some of the $40- $60 pre's.

 

[Lavane]

They make sense sometimes. My subsonic filter runs a basic ac wart. No poor quality switch mode electronics or filters, just 16 vac output. This kept a 120 vac mains connection outside of the box, and all of the safety concerns and potential for noise that involved. It just comes in and runs through a rectifier and regulator. Also lets the box be nice and small since nothing inside needs space for noise isolation, voltage insulation, or room for a transformer.


Not a solution for all issues but for that specific one it does real nice.

The Active subsonic filter I built works very well. I used a switch mode supply and an added filter board.

 

[63pontiacgp]

I played around today using one table with a Nagaoka MP-200 installed on both the Mp-7 and the Pyxi. Back and forth I went using Dire Straits Brothers In Arms (RL Masterdisk) version. If I had to pick one over the other I'd go with the Darlington. To me it slightly edges out the Sota. I don't have the "words" reviewers use, I just shut my eyes and listen. The MP-7 wins, for me.
I'm in the process of simplifying and am going down to one table. I just ordered a "gasp" new Technics and will run it with the MP-7.

Mike

Update: I did not go to a single table, just couldn't do it. I did buy another MP-7 and have one on each the Technics and the Dual. I donated the Pyxi on "Auction for AK". For me the MP-7 just sounds right, YMMV. Have not had the "urge" to get another phono stage at this point. Maybe I'm cured?

Mike

 

[Sgt Shultz]

Update: I did not go to a single table, just couldn't do it. I did buy another MP-7 and have one on each the Technics and the Dual. I donated the Pyxi on "Auction for AK". For me the MP-7 just sounds right, YMMV. Have not had the "urge" to get another phono stage at this point. Maybe I'm cured?

Mike

Recently added this to my media rm 2-channel rig and it's outstanding, super quiet and offers lots of loading options for both MM and LOMC. Only available through the manufacturer so no middleman markup, the Well Tempered Lab was never happier.

 

[ceylon]

Update: I did not go to a single table, just couldn't do it. I did buy another MP-7 and have one on each the Technics and the Dual. I donated the Pyxi on "Auction for AK". For me the MP-7 just sounds right, YMMV. Have not had the "urge" to get another phono stage at this point. Maybe I'm cured?

Mike

hey, "both" is a great word. man, after you owned all those phono amps, darlington labs mp-7 is the winner!

 

[Mr Boochie]

hey, "both" is a great word. man, havin auditioned all those phono amps, darlington labs mp-7 is the winner!

Have you tried the Project Tube DS2 Phono Box?

I've had mine for over 5-years now (how time flies). The 5751 tubes really are nice in this unit.

`

Sideshow.
Blue Magic - ATCO Records. SD 7038. Presswell pressing. 1974.
Run-out: ST-C-733001-B AT GP PR

 

[MisterDK]

hey, "both" is a great word. man, havin auditioned all those phono amps, darlington labs mp-7 is the winner!

Guessing that you didn’t care for the 834 clone..?

 

[ceylon]

Guessing that you didn’t care for the 834 clone..?

i own two; i dont own a darlington. see the last post made by @63pontiacgp. im gonna edit mine.

 

[ceylon]

Have you tried the Project Tube DS2 Phono Box?

I've had mine for over 5-years now (how time flies). The 5751 tubes really are nice in this unit.

View attachment 3084067`

Sideshow.
Blue Magic - ATCO Records. SD 7038. Presswell pressing. 1974.
Run-out: ST-C-733001-B AT GP PR

i had the D2 for a while. i was auditioning the D2, the rega fono and ifi zen. i and all my gusts picked the pro-ject every time. never heard the DS2--i bet its fantastic

 

[Mr Boochie]

i had the D2 for a while. i was auditioning the D2, the rega fono and ifi zen. i and all my gusts picked the pro-ject every time. never heard the DS2--i bet its fantastic

Thanks for the comment!

It's the best phono pre-amp that I've tried.

With the stock Tungsol (Russian) 12AX7 --- the instruments, vocal clarity, and separation were just okay. Really, it was not well defined. I've used the Russian Tungsol in guitar amps. In my opinion, it is a terrible tube.

I rolled Philips-Miniwatt ECC83, Mullard (UK) ECC83, RCA 7025, NEC 12AD7, Valvo E83CC.

NOTHING comes close to the Raytheon windmill-getter 5751 in this pre-amp. Separation and the lowest background noise. It wasn't close. And these mil-spec 5751 tubes last forever.

It was like all the hazy fog was lifted. I love 5751, but I was worried about RIAA EQ. I've had issues with that before in tubed phono sections.

No problems. It must be in a buffer section. It just shows you that the buffer section can make a difference to the final sound.

Blue Bayou.
Off Linda Ronstadt's "Simple Dreams." Nautilus Recordings. NR26. 1/2-speed remaster SuperDiscs. 1981.
Run-out: NR 26 A1 IAM RD 1/2 KM - 6432 - A1

 

[MisterDK]

i own two; i dont own a darlington. see the last post made by @63pontiacgp. im gonna edit mine.

Yes, I read it.
You wrote that the “MP-7 is the winner” - so I wasn’t sure.

Mike had one of the 834 clones too, but I guess it didn’t satisfy. My recently built 834 clone sounds pretty sweet to me; better than my prebuilt 834 clone and though it’s close, even better than my my new Schiit Skoll - and a host of other phono pre’s I’ve used over the years..

I don’t mind having a few phono preamps around. They’re quiet, don’t eat much and some are kind of cute... I have a few turntables here to use them with and I’m planning on building a dual or tri arm table, too.

 

[Mr Boochie]

Yes, I read it.
You wrote that the “MP-7 is the winner” - so I wasn’t sure.

Mike had one of the 834 clones too, but I guess it didn’t satisfy. My recently built 834 clone sounds pretty sweet to me; better than my prebuilt 834 clone and though it’s close, even better than my my new Schiit Skoll - and a host of other phono pre’s I’ve used over the years..

I don’t mind having a few phono preamps around. They’re quiet, don’t eat much and some are kind of cute... I have a few turntables here to use them with and I’m planning on building a dual or tri arm table, too.

What coupling caps and tubes did you load into your DIY?

Thanks!

 

[Hajidub]

Yes, I read it.
You wrote that the “MP-7 is the winner” - so I wasn’t sure.

Mike had one of the 834 clones too, but I guess it didn’t satisfy. My recently built 834 clone sounds pretty sweet to me; better than my prebuilt 834 clone and though it’s close, even better than my my new Schiit Skoll - and a host of other phono pre’s I’ve used over the years..

I don’t mind having a few phono preamps around. They’re quiet, don’t eat much and some are kind of cute... I have a few turntables here to use them with and I’m planning on building a dual or tri arm table, too.

He rehomed one of his 834's to me, love this preamp! Dead quiet, only gripe is the DC battery requirement for MC function. 63 liked it also, but wanted tubes to be visible.

 

[MisterDK]

What coupling caps and tubes did you load into your DIY?

Thanks!

Tubes in V1 and V2 are some Westinghouse branded Mullard, from what I can tell; they’re printed with “MADE IN ENGLAND”. I haven’t figured out from which Mullard factory they came as the code characters are hard to read. They were true NOS/NIB. In V3 I’m using a Chinese Shuguang. The cheap Shuguang is actually less microphonic than the NOS tubes.
Coupling caps are some ERO (vintage Vishay) and vintage Sprague, from memory. Other than some of the RIAA parts though, much of what I used was kit supplied. I did add cathode bypass caps and heater caps on the PCB underside, upped one large PS filter cap in capacitance and voltage using Elna Cerafine, added a PS choke, and left out the rumble filter. I was thinking I could add fancier caps later on but it sounded so good from first listen, I hadn’t given it another thought.. Was thinking about building another one of these as I have another PS transformer and choke.. If I do, I may add attenuation, two sets of inputs, fancier caps, etc. They’re fun to build..

 

[63pontiacgp]

He rehomed one of his 834's to me, love this preamp! Dead quiet, only gripe is the DC battery requirement for MC function. 63 liked it also, but wanted tubes to be visible.

Yep, I like to see the tubes

Mike

 

[ceylon]

Yep, I like to see the tubes

Mike

dam strait