TOS vs Dmars

[sdp1234]

Ive been away from the forum and amp building for a while now.  A while back i started working on a TOS type amp.   I cant find where the Dmars came to life? Was it before or after the TOS? What are the differences? 

[tubenit]

The D'Mars came after the TOS.  They are significantly different.  The TOS has more overdrive and sustain & a pretty strong vowel tone with easier blooming where the notes sort of open up with harmonics.

The D'Mars is a Marshallish preamp.  The amp has more contrast between clean and OD.  It has a very clear transparent tone in either clean or OD.  It has less vowel tone, less blooming and less sustain.  However, it has the most musically sweet tone of any amp that I've built or played.

D'Mars soundclip:   http://www.soundclick.com/player/single_player.cfm?songid=11842172&q=hi&newref=1

TOS  soundclip:   http://www.soundclick.com/player/single_player.cfm?songid=9488477&q=hi&newref=1

With respect, Tubenit

[tubenit]

Compare the schematics.

With respect, Tubenit

[Mike_J]

The D'Mars came after the TOS.  They are significantly different.  The TOS has more overdrive and sustain & a pretty strong vowel tone with easier blooming where the notes sort of open up with harmonics.

The D'Mars is a Marshallish preamp.  The amp has more contrast between clean and OD.  It has a very clear transparent tone in either clean or OD.  It has less vowel tone, less blooming and less sustain.  However, it has the most musically sweet tone of any amp that I've built or played.

D'Mars soundclip:   http://www.soundclick.com/player/single_player.cfm?songid=11842172&q=hi&newref=1

TOS  soundclip:   http://www.soundclick.com/player/single_player.cfm?songid=9488477&q=hi&newref=1

With respect, Tubenit

Tubenit

The only logical conclusion from listening to your sound tracks is to build one of each.  With an A/B/Y switch it would make a most excellent rig.  Can these amps both fit in a 19 inch chassis?

Thanks
Mike

[sdp1234]

Thanks Tubenit.  Looks like it is the TOS right now and maybe the Dmars another time.  I'm looking to be able to dial in a bit of that Dumble tone.  I kind of hear it as a sax type of sound and I'm thinking that is what you call the "vowel sound"?

[tubenit]

The TOS is closer to the more familiar Dumble tone then the D'Mars is, IMO. 

In some ways, I think the D'Mars has some of the sweetness that one hears in some of the Dumble amps that are not geared towards an overdriven tone, IMO.  However, still different obviously.

I think either amp could be built into a 19" chassis.

With respect, Tubenit

[sdp1234]

Still reading and looking at schematics.  How would you describe the basic tone differences between the TOS, TOS 2 and TOS3?   Thanks.

[sdp1234]

On my previous post I believe it was a TOS 3-12 and not a TOS 3.

[tubenit]

I think the very original TOS design was GREAT!  Nothing "needs" to be changed from that.

Having said that,  adding a cathode follower behind the 5879 did add some smoothness to the overdrive.  You could easily use a mosfet to do that and mount the mosfet on a small board and still use Doug's TOS Hoffman style layout board.

IF I build another one (at some point), then I personally would add the mosfet CF behind the 5879 and keep everything else like the original design.

IF you like a little more chime and grit in the OD, then leave the mosfet CF out and just build it like the original.

Every TOS version I did sounded good to me.  The following ones sounded different with strengths and weakness compared to the original design.  That's probably the best answer I can give you.

With respect, Tubenit