the BM like most ODS used orange drops but I see no reason you can't use your mustard caps. Resistor types are marked on the layout.
Should make for an intersting amp, will it sound 100% like a BM? probably not but I'm sure it will be a great sounding amp. I have a JTM45 with KT66's and it's a lovely sounding amp. a 50w BM should be great with KT66's.
You can always swap out the mustards for orange drops , I've a feeling the BM had 715 caps which are polypropylene not sure what the mustards are so you migth want to check. Not usre how much difference it will make. I Put some SOZO's in my last BM build
M
Bluesmaster pre with non-hrm overdrive
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- norburybrook
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Re: Bluesmaster pre with non-hrm overdrive
Hi !
Thanks for info,I think Mustards (Philips,Bianchi ) are self-healing construction polyester foil cap. and Orange 6ps are polyester fim.so it is worth to try...as let them in junk box
gsb
Thanks for info,I think Mustards (Philips,Bianchi ) are self-healing construction polyester foil cap. and Orange 6ps are polyester fim.so it is worth to try...as let them in junk box
gsb
Re: Bluesmaster pre with non-hrm overdrive
I don't really remember this thread but I will chime in here
As far as the resistors go? it's really pretty simple IMO here is a general consensus among experienced builders myself and others notice.
If you want the amp to take on a more aggressive stance go with the MF's in the signal path since they can be (depending on the resistor type) a bit brighter more articulate and for lack of a better word "in your face". The feel is generally tighter as well .CF's go the opposite direction can color the sound somewhat again depending on the resistor type. These tend to be a bit smoother sounding less aggressive less focused and adds a bit of 2nd order when in OD, so it's a matter of taste and style of music you play. The BM is already designed to be more of an aggressive sounding amp for Rock and Blues (hence the name Bluesmaster) The BM can be at times bit bass heavy with a looser feel mainly due to the hotter (Marshall style) PI design 50K mid pot and .022 mid-cap and lower slope resistor less GNFB no NFB V1 etc.etc.As far as the Mustards go?.Go for it.I've used these in ODS amps with good results!
The problem IMO with going to a cathode biased OPT section is when in OD and the amp cranked you may have a problem with the low end being too loose and muddy sounding and at high vol levels may experience some blocking distortion...I wouldn't go any higher than 5uF on the cathodes and for higher volume use, add a fixed bias/cathode biased switch on it.But that is just me
Again! these are subtle changes..Some people notice it? others not so much.It all depends on your frame of reference, what amp you are comparing it too and other factors(guitar/speakers/cabinet type/tubes, and how you run the thing)
The Bluesmaster is IMO Dumbles response to the popularity and those wanting something more JCM 800-ish which was a wildly popular amp in the 80's .If you really study the design "the BM is a combination of both the JTM 45 (on clean channel)and JCM 800 (Overdrive channel boost on)"
Tony
As far as the resistors go? it's really pretty simple IMO here is a general consensus among experienced builders myself and others notice.
If you want the amp to take on a more aggressive stance go with the MF's in the signal path since they can be (depending on the resistor type) a bit brighter more articulate and for lack of a better word "in your face". The feel is generally tighter as well .CF's go the opposite direction can color the sound somewhat again depending on the resistor type. These tend to be a bit smoother sounding less aggressive less focused and adds a bit of 2nd order when in OD, so it's a matter of taste and style of music you play. The BM is already designed to be more of an aggressive sounding amp for Rock and Blues (hence the name Bluesmaster) The BM can be at times bit bass heavy with a looser feel mainly due to the hotter (Marshall style) PI design 50K mid pot and .022 mid-cap and lower slope resistor less GNFB no NFB V1 etc.etc.As far as the Mustards go?.Go for it.I've used these in ODS amps with good results!
The problem IMO with going to a cathode biased OPT section is when in OD and the amp cranked you may have a problem with the low end being too loose and muddy sounding and at high vol levels may experience some blocking distortion...I wouldn't go any higher than 5uF on the cathodes and for higher volume use, add a fixed bias/cathode biased switch on it.But that is just me
Again! these are subtle changes..Some people notice it? others not so much.It all depends on your frame of reference, what amp you are comparing it too and other factors(guitar/speakers/cabinet type/tubes, and how you run the thing)
The Bluesmaster is IMO Dumbles response to the popularity and those wanting something more JCM 800-ish which was a wildly popular amp in the 80's .If you really study the design "the BM is a combination of both the JTM 45 (on clean channel)and JCM 800 (Overdrive channel boost on)"
Tony
Last edited by talbany on Sat Sep 08, 2018 9:13 am, edited 1 time in total.
" The psychics on my bench is the same as Dumble'"
Re: Bluesmaster pre with non-hrm overdrive
That was a long time ago! All caps used in this amp were 6PS Orange drop, all plate resistors were Dale RN65D new type.
I am curious on the old type Dale resistors, is there a good source to get them?. Definitly want to try them.
I am curious on the old type Dale resistors, is there a good source to get them?. Definitly want to try them.
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Re: Bluesmaster pre with non-hrm overdrive
hi ,
Lot of useful infos ,great ,about bass heavy -on jtm45 build a have reduced post PI caps from 0,1m to some 0,047 with good result.
thanks gsb
Lot of useful infos ,great ,about bass heavy -on jtm45 build a have reduced post PI caps from 0,1m to some 0,047 with good result.
thanks gsb