[masi61]

So today I finally hooked my new Bryston BP2-MM phono preamplifier into my Linn Sondek LP12 turntable that has not been used since 1999!

I have been listening to digital all this time, some of it not very good sounding either! This was from back in my NAD 2200 days. Now I have a much better system with a BP26 preamp powered by the MPS-2 power supply. I got an extra BP-26 umbilical cord for the BP2-MM to the MPS-2 outboard power supply.

So I see where the default capacitance loading is 100pF with no tweaking with jumpers. I looked up the capacitance for my Linn K9 MM cartridge and it says 200pF. So from the owner’s manual it appears that I will need to move one jumper over per channel to increase the capacitive load from 100pF to 200pF.

I’ve already used a T8 Torx bit to remove the 4 screws to get the cover off - super easy. You got to love the build quality of how clean and well laid out everything is under that cover. My turntable will need to be wall mounted since my 2nd story living room makes the suspended subchassis bounce when you walk around. Once sitting still, it is fine for now on the glass table top of my equipment stand.

Just a question about changes in SQ to expect from changing to the proper 200pF capacitance load: will this improve the bass response? It seems just OK on the first record I am playing, but maybe too lean and bright. The stereo separation, quietness and detail retrieval are all great BTW.

[masi61]

There was a question in there - about how the capacitance load impacts sound quality. I was hoping to get some assistance here.

Also, in auditioning the new Bryston BP2-MM I have now detected a pretty significant hum problem. I first heard it during the quiet passages between songs. Now that I’m aware of it, I hear it all the time.

I’m using the MPS-2 power supply and was told I needed to use the umbilical for the BP-26 to power the BP2-MM. Apparently the provided umbilical is for the 1/3 chassis power supply only. I got the recommended one for my MPS-2 and I still have a hum issue.

I’m hoping to get some suggestions on things to check to trouble shoot this issue. I am using a BIT-15 power conditioner too BTW.

I’m going to make sure my outlet is properly grounded. That might be the cause of the hum right there, you see I don’t think my second story living room’s outlets in my 1959 built house are grounded at all.

Right now my Linn LP12 turntable is on the top shelf of my equipment rack, above the MPS-S, the BP-26 and my Bryston DAC.

I did message Bryston through the website and am awaiting a reply. I tried the phone number and email address for USA customers in Vermont and got a “this phone number has been disconnected” message and “undeliverable mail” message on the email. Please help!

[James Tanner]

HI

I spoke to Mike and he is getting back to you.

Phone number in Vermont is - 802-485-3481

james

[Speedskater]

The capacitive  load a phono cartridge sees is the sum of the cable capacitance and the phono pre-amp input stage capacitance.
It only affects the very high frequency response.
Do a search on:
phono cartridge capacitance matching
phono cartridge capacitance loading
also look at the images

[masi61]

Thank you James. I did call the number you provided and he had me try a few things. The hum goes away when the right & left RCA inputs are disconnected. So the MM phono stage with the RCA out interconnects connected to the “AUX” input is as silent as my 2 SPDIF sources through my BALANCED 1 input.

Why I’m getting the hum with the Linn is a bit of a mystery right now. The turntable will be going to Thomas O’Keefe in Ann Arbor for work this summer & getting a new cartridge (Adikt - haha you gotta love the naming of Linn branded products) and a new motor update.

[James Tanner]

Thank you James. I did call the number you provided and he had me try a few things. The hum goes away when the right & left RCA inputs are disconnected. So the MM phono stage with the RCA out interconnects connected to the “AUX” input is as silent as my 2 SPDIF sources through my BALANCED 1 input.

Why I’m getting the hum with the Linn is a bit of a mystery right now. The turntable will be going to Thomas O’Keefe in Ann Arbor for work this summer & getting a new cartridge (Adikt - haha you gotta love the naming of Linn branded products) and a new motor update.

Does the Linn tonearm have a separate ground wire?

james

[masi61]

I'm assuming that the tonearm does have a separate ground wire. There is a wire that is connected to the RCA cables and I connected it to the ground lug on the BP2-MM. We tried it connected and disconnected and it made no apparent difference in the hum. I'm not sure if the ground wire goes all the way up to the tonearm leads or where it originates inside the turntable, I haven't investigated it that deeply yet.

I thought that having the turntable positioned directly above the MPS-2 power supply might be causing some magnetic interference so I shifted the turntable further down the glass top of the equipment cabinet (it is a wide TV cabinet with glass shelves). This didn't make any difference either.

[masi61]

The capacitive  load a phono cartridge sees is the sum of the cable capacitance and the phono pre-amp input stage capacitance.
It only affects the very high frequency response.
Do a search on:
phono cartridge capacitance matching
phono cartridge capacitance loading
also look at the images

Thank you @Speedskater - I will do the searches you suggest. My initial thoughts on sound quality are that it is quite good at the 100 mF setting. It is mainly the hum right now that is preventing the SQ from becoming stellar. I'm also going to need to get one of those carbon fiber record brushes. Even little bits of dust on a record seem to be creating a moderate amount of surface noises.

[masi61]

Does the Linn tonearm have a separate ground wire?

james

Yes, there is a separate ground wire which I have attached to the lug on the back of the BP2-MM. This hum seems to come and go. I notice that when I turn on my turntable and start an album I don't hear it at first. By the end of one side of an album the hum sort of shows up and stays around so I have to shut the turntable off and switch back to a digital source for a while.

I do plan to get the Linn back on the old Sound Organization wall stand soon which may give less cable interference to adjacent components and power supplies.

Also, after having several LP "auditions" in the past 2 weeks and must say I am super stoked about listening to vinyl records again. Garage sale records that I paid $2 each for from Blue Oyster Cult, and Procul Harem sounded quite good. All of the great sonic qualities from the Bryston 4B2 amp, BP26 preamp and my Thiel CS3.6 speakers are all sounding better than ever right now. Presently I upgraded the power cord from my BIT-15 power conditioner to my MPS-2 power supply and just that change alone has been a minor revelation.