Owner Manuals

0 Members and 1 Guest are viewing this topic. Read 1956 times.

Hogg

Owner Manuals
« on: 21 Aug 2014, 06:00 pm »
Roger any chance you will post the owners manuals for your products on the MR website?  I want to bias my RM10 Mk II but can't find my manual.  I really don't like playing telephone tag with the MR support number.  Thank you in advance.

                                               Jim Waugh

tubegroove

  • Jr. Member
  • Posts: 64
Re: Owner Manuals
« Reply #1 on: 21 Aug 2014, 06:15 pm »
It's pretty simple with the RM10 MkII.
Set your multimeter to DC Volts.  In front of each pair of EL84 tubes are two probe points. The left one is negative and the other positive in each pair
Put your multimeter probes in there and set the bias to 270mV. There is a pot behind V3and V4 which you can use to adjust. The pot adjusts the bias per pair
I think this is the value that Roger sets when he ships from the factory and one that he recommends
That's it, you are all set. If your tubes pairs are well matched and in good condition the bias should stay firm for a long time.
Check every few months perhaps
Hope this helps

Hogg

Re: Owner Manuals
« Reply #2 on: 21 Aug 2014, 08:42 pm »
Thank you!!   I knew the bias procedure but not the mV setting.  I found a source on-line that cited 300mV instead of the 270mV you suggest.   Is 270mV MF's spec? 

                                           Jim

Clio09

Re: Owner Manuals
« Reply #3 on: 21 Aug 2014, 09:04 pm »
My manual says 300mv.

BTW - what speaker is that pictured in your photo.

Hogg

Re: Owner Manuals
« Reply #4 on: 21 Aug 2014, 11:49 pm »
Thank you, Clio09.  I used the 300mV spec to bias my new set of Gold Lion EL84's; great tubes.  The speaker avatar is a picture of my Tannoy Glenair 15's.  No, the RM10 doesn't drive them very well.  I'm using the RM10 on a pair of Spendor 2/3E's.  Thank you again.

                                                                                                           Jim

tubegroove

  • Jr. Member
  • Posts: 64
Re: Owner Manuals
« Reply #5 on: 22 Aug 2014, 02:49 am »
Thank you!!   I knew the bias procedure but not the mV setting.  I found a source on-line that cited 300mV instead of the 270mV you suggest.   Is 270mV MF's spec? 

                                           Jim
Jim
Didn't know if you needed the bias procedure or not so included that just to be complete
Yes the manual says 300mV but as I recall Roger uses 270mV for longer tube life. Either is fine is what I recall he advised

Btw, have you tried the Ei 6BQ5s or other brands as well in your RM10? I hear good things about the Gold Lion EL84 but trying to get a sense if they are much better than the Ei
Thanks

Roger A. Modjeski

Re: Owner Manuals
« Reply #6 on: 22 Aug 2014, 03:05 am »
Thank you, Clio09.  I used the 300mV spec to bias my new set of Gold Lion EL84's; great tubes.  The speaker avatar is a picture of my Tannoy Glenair 15's.  No, the RM10 doesn't drive them very well.  I'm using the RM10 on a pair of Spendor 2/3E's.  Thank you again.

                                                                                                           Jim

We think the EI tubes are much better than the Gold Lions when it comes to EL-84's

I am curious why the RM10 doesnt drive the Tannoys very well?


Clio09

Re: Owner Manuals
« Reply #7 on: 22 Aug 2014, 03:05 am »
Nice speaker, I will have to look into it. I ran my RM-9 on the Spendor 7/1s which are the floor standing version of your 2/3s. I still rue selling my 1/2e speakers five years ago and although I love my current speakers I am now looking for another set of those Spendors.

bdp24

  • Full Member
  • Posts: 883
Re: Owner Manuals
« Reply #8 on: 22 Aug 2014, 01:00 pm »
I asked this in the new bias quiz post, but thought I'd put it here too, as bias is being discussed. The RM200 manual lists the recommended and maximum bias settings for all the tubes that can be used in the amp, but not the new KT120 tubes. Roger, can you specify the bias settings for various 120 tubes when used in the RM200?

Roger A. Modjeski

Re: Owner Manuals
« Reply #9 on: 22 Aug 2014, 04:58 pm »
You can bias a KT-120 at a meter reading of 50-65 mV (50-65 mA idle current) as it has higher dissipation than a KT-88. Whether it sounds better there is up to you. I usually bias them at 40. Higher current does shorten life and run the amp hotter, though still much cooler than most amplifiers. I wonder if designers of high idle current amps bother to check if they are getting any advantage from high idle current or just assuming that it is better?

I am finding in my OTL amp that higher bias does not always result in lower distortion. One must be careful about what one assumes without checking it out.


bdp24

  • Full Member
  • Posts: 883
Re: Owner Manuals
« Reply #10 on: 22 Aug 2014, 08:01 pm »
40 it is, thanks.

Hogg

Re: Owner Manuals
« Reply #11 on: 26 Aug 2014, 07:27 pm »
We think the EI tubes are much better than the Gold Lions when it comes to EL-84's

I am curious why the RM10 doesnt drive the Tannoys very well?

I'll try the EI tubes in the future.  I like the Gold Lions so far.

The RM10 doesn't have the drive to satisfy the Tannoy's.  Dynamic contrasts are paler and the overall presentation is a little subdued.  I use a Jadis 50S with KT88 tubes to drive the Tannoy's.  I've used 6CA7's, KT66's and EL34's with the Jadis and find similar differences with the RM10.  It may be the different tubes.  In any case I like the RM10 very much.  It's super-quiet and reliable.

Roger, you didn't answer my original question; why not post user manuals including bias procedures on your website.  Most other manufacturers do this as a courtesy to their customers.

Thank you.

                                 Jim

Roger A. Modjeski

Re: Owner Manuals
« Reply #12 on: 27 Aug 2014, 01:49 pm »
We are looking into putting manuals on line. Currently we are just too busy with the move. I will ask Ben to put it on his list. Its not as simple as one might think getting everything together, scans, uploading.

We would welcome someone in the Bay Area who would like to go through our files of manuals and post them. Please write me here.