[sean-xenos]

I'm looking for an upgrade for my clone.

Though the synergy of the RS-1s and the RA-1 is quite good
as the tonal colour and the timbre feel right,
I believe that the soundstage and sense of depth produced could be better.

What makes me believe that?
Well, I auditioned the Lehmann Black Cube at a local dealer and it really opened up the stage impressively, produced great seperation of instruments and depth of sound (though the tonal balance was not perfect, bass was quite thin).

I've heard from other competent headphone lovers that the C.E.C. HD53 (v.8.0) and the Ray Samuel Raptor are able to improve soundstaging with RS-1s as well.

I know that RS-1s are not famous for their width of soundstage but there seems to be real potential if driven by the right amp.

Is there a DIY amp that is capable of producing a soundstage that is wide along all three axis with the RS-1s ?

Any suggestions based on own experiences would be great

[size=xx-small]Edited by moderator[/size]

 

[rickcr42]

If by DIY amp you mean an established product then look to the Borbley Hybrid Amp.

Low voltahge tube front end to class-a mosfet output stage.

If you want to buy an amp with those qualities look at the Melos headphone amps.also hybrid designs.

It has been my personal experience (taste) that Class-A mosfet current stages with a tube or jfet front end (gain/biuffer stage) get Grado cans more right than any other topology available.

 

[dsavitsk]

I think Rick is largely right here. If, however, you are looking for a cheaper option, the Millett hybrid is also pretty good -- particularly, I would think, if you double up on the buffers. While not nearly as detailed, it is a bit less hard sounding than the Melos. Both (and probably all 3) are tons better than the RA-1.

 

[sean-xenos]

Quote:

Originally Posted by rickcr42 If by DIY amp you mean an established product then look to the Borbley Hybrid Amp...

Hi rickcr42,

thanks for your recommendations

By DIY I mean either a kit with selected parts like the Borbley or a DIY project with just a pcb and an instruction and the rest I may have to do on my own (with the help of this Forum

)
I'm not looking for a fully assembled commercial product, because DIY is fun and experience for me. I like to understand what I'm building, like to experiment with different parts and options (rolling tubes or opamps, changing values etc.)
And furthermore I expect DIY amps to offer better value for the money than commercial products.

 

[rickcr42]

The price is not yet settled but will be soon and i am thinking if past experience any indication it will be competitive in price while offering performance miles above what you caould get at that price piont.the wellborne kits are truly high end

preliminary details here :

http://www.welbornelabs.com/hyb.htm

the topology is simple but well thought out and in fact I had built one years ago and it really is a very nice amp.

The millett is a comprimise design. A nice design but the monolithic buffers as the output stage are bettered by a full Class-A CCS'ed output stage as in the Borbely.The tube used in the front end is one that can be a bit dry sounding but done right can sound deadly accurate.

the cmments about the melos having a "hard" sound is one that is very version dependant and it is in my mind Melos never really settled down and made just ONE version the best they could but from looking at the schematics and all the written in 'revisions" was a design always in motion and one amp may be totally different from the next even though the name and number the same.
Most likely that is what caused the companies demise.the unti to unit variables that would get a good review then a bad one.A product needs to be "finished" and sold for what it is,not what it could be

BTW-more information is available at borbely.de

 

[sean-xenos]

Quote:

Originally Posted by dsavitsk I think Rick is largely right here. If, however, you are looking for a cheaper option, the Millett hybrid is also pretty good -- particularly, I would think, if you double up on the buffers. While not nearly as detailed, it is a bit less hard sounding than the Melos. Both (and probably all 3) are tons better than the RA-1.

Hi dsavitsk,

thanks for mentioning the Millet Hybrid.

As the last thread for this amp http://www6.head-fi.org/forums/showt...8&page=9&pp=20
is a bit complex,
is the pcb offerd by diycable.com the latest version?

 

[dsavitsk]

Quote:

Originally Posted by sean-xenos thanks for mentioning the Millet Hybrid. is the pcb offerd by diycable.com the latest version?

Sort of. There is an ongoing group buy on this board for a revised pcb that does not change the circuit, but does change the layout (you missed the ordering portion of the GB, but you should contact the people in charge as they are going to have a few extra PCBs). The DIYCable version should sound the same, however.

Also, Rick mentioned the output buffer on the Millett as the weak part of the amp. It is possible to replace this with a discrete buffer, but it will take some extra work. Check out the GB project page for more info.

All of that said, the Millett is the "CMoy" of tubes, so you should not confuse its performance with the amps Rick mentioned. The Millett is good for what it is (and it is tons nicer than an RA-1,) but the other two are clearly the more advanced designs.

-d

 

[rickcr42]

Quote:

Also, Rick mentioned the output buffer on the Millett as the weak part of the amp. It is possible to replace this with a discrete buffer, but it will take some extra work. Check out the GB project page for more info.

I think this an absolute wrong move.Use the millett if that is your choice for what it is or look elsewhere.

I never could understand why so many want a certain thing so bad then try to make it something else.Changing the basic nature of a fully engineered amp makes it something new and not just a "version' of that amp and like most things,trying to weasle in something not specifially designed for that particular application/amp is and must be a comprimised design.

Quote:

All of that said, the Millett is the "CMoy" of tubes, so you should not confuse its performance with the amps Rick mentioned. The Millett is good for what it is (and it is tons nicer than an RA-1,) but the other two are clearly the more advanced designs.

Maybe more accurate would be the "cmoy of hybrids" .This is the "cmoy" of tube amps :

http://headwize.com/projects/showfil...=cmoy5_prj.htm



Becasue of its low voltage low gain nature of the Millett Hybrid it is much easier to do than a typical tube stage and cost FAR less due to the voltage requirements.As I imagine Pete intended.He HAS full tuvbe amps that are neither cheap or easy builds for the inexperienced so this design is not an afterthought but intended for a "niche".


Pete Millet took the path of simplicity where possible and added complexity where it did the most good and this is a replacement if you will for an opamp based headphone amp for the home.an alternative to the same old in the fixed amp position.
Using a buffer as the output stage relaxed the requirements for biasing that stage and designing a stable DC free output which usually means matching dvices and choosing carefully
If cost is factored in this is a no brainer apprroach but if ultimate performance is your goal then a fully realised output stage designed for use with that particular front end is the way to go.

You all need to realise that everything has sound and you attempt to complimient the front end sound with the output stage so that the sum of the parts is better than each stage if taken alone.
This is the secret to getting good sound out of the RA-1 (the sound of each individual part selected for the overall end sound) and any good design that is from start to finish having a goal in mind.
The reason the millett amp sounds a sgood as it does is the very choices made from the start.fiddle around with things and you have a different amp and one that may cost a lot more before you are through but sound no better if not worse.

There is a place for all these amps and each can be a stepping stone.I hate monolithic opamp ams with a passion but they are a neccessary evil for a portable amp.Headroom has actually managed to make an amp,the Max.that while based on the OPA627 I could easily live with forever as my only amp so good sound IS possible.

all tube is not an easy or inexpensive build and mostly it is really tough to get an amp that is universally good with any and all cans.

the hybrid offers some of each but if grados are the cans of choice then the absolte best way to go in my own experience.

choices are a good thing but sometimes hard to decide which is the way to go.

 

[sean-xenos]

Quote:

Originally Posted by rickcr42 ..... the hybrid offers some of each but if grados are the cans of choice then the absolte best way to go in my own experience. choices are a good thing but sometimes hard to decide which is the way to go.

Yes, Grados are certainly my cans of choice

I had a look at borbelyaudio.com,
Mr Borbely offers two headphone amp kits:
One is a single-ended pure class A amplifier based on JFETs and MOSFETs,
the second is a single-ended Hybrid Tube/MOSFET amp.

I asked Mr Borbely for a recommendation which one to use with the RS-1s for best soundstaging and tonal accuracy.
Both kits seem to be quite costly (around 400 € incl. PSU).

BTW does anyone have experiences with the Gilmore Dynahi and RS-1s (I know it's not a hybrid amp, but might be worth some consideration)?

 

[pbalcer]

Quote:

Originally Posted by sean-xenos I know that RS-1s are not famous for their width of soundstage but there seems to be real potential if driven by the right amp. Is there a DIY amp that is capable of producing a soundstage that is wide along all three axis with the RS-1s ?

There is such a potential.

I also started with RA1 clone. But later on I built my own class A amp and that was what my RS1 needed to really open up. I guess my preferences (liquid, smooth, tube-like sound) also played role here.

If you want to try something simple but good sounding with RS1, my design is available on the web: http://www.geocities.com/bpiotrek/ha1_e.html
You can build this circuit using regular components (practically any PNP/NPN transistors will work in this design) and without special PCB in just a few hours - just to check it out.

Anyways, high current, pure class A is what RS1 need to really shine!

 

[rickcr42]

Quote:

I had a look at borbelyaudio.com, Mr Borbely offers two headphone amp kits: One is a single-ended pure class A amplifier based on JFETs and MOSFETs, the second is a single-ended Hybrid Tube/MOSFET amp.

The circuits are identical except for the actual front end part used and operating points.
I have all the schematics/parts lists/files etc and it is clear the jfet stage is pretty much a
"drop in" replacement to make a purely SS version of the amp.Jfets and ytiodes act the same as a gain cell so are easily used in the same type of circuit with the proper power supply and biasing adjustments.
The sound I can not comment on having only made a version of the hybrid but there is an online review of the Aural headphone amp at 6 moons which is the borbely jfet/mosfet as a finished amp.

 

[DigiPete]

Hi,

You could look into a M³ amp, which is a JFET to a MOSFET. There is a thread on it here:

http://www6.head-fi.org/forums/showthread.php?t=109760

DigiPete

Quote:

Originally Posted by sean-xenos Yes, Grados are certainly my cans of choice I had a look at borbelyaudio.com, Mr Borbely offers two headphone amp kits: One is a single-ended pure class A amplifier based on JFETs and MOSFETs, the second is a single-ended Hybrid Tube/MOSFET amp. I asked Mr Borbely for a recommendation which one to use with the RS-1s for best soundstaging and tonal accuracy. Both kits seem to be quite costly (around 400 € incl. PSU). BTW does anyone have experiences with the Gilmore Dynahi and RS-1s (I know it's not a hybrid amp, but might be worth some consideration)?

 

[sean-xenos]

Quote:

Originally Posted by DigiPete Hi, You could look into a M³ amp, which is a JFET to a MOSFET. There is a thread on it here: http://www6.head-fi.org/forums/showthread.php?t=109760 DigiPete

Hi DigiPete,

I'm not sure if the M³ is actually capable of producing a wide soundstage and accurate tonality with the RS-1s.
Any specific experiences?

 

[rickcr42]

Quote:

You could look into a M³ amp, which is a JFET to a MOSFET. There is a thread on it here:

the M3 is has an opamp front end,not a jfet/mosfet amp and is based on the SDS Labs project at Headwize.

I have not heard this amp,have built the SDS,but so far the best sound I have gotten from my Grados is with a straight SE Class-A mosfet output stage for current delivery and either an SE Jfet or Se triode front end,simplicity rules the grado roost mostly until I hear better.
You need to think in terms of 200-250 ma drive current and that must be class-a drive if the goal is a diffuse and spacious sound field from the RS-1 cans.
Easy to drive straight out of any headphone jack they are plugged into,not so easy to get full performance capabilities from.

The Mapletree Ear series has also gotten great reviews with the RS-1 though again I can not comment from actual listening experience

 

[sean-xenos]

Quote:

Originally Posted by rickcr42 ....,but so far the best sound I have gotten from my Grados is with a straight SE Class-A mosfet output stage for current delivery and either an SE Jfet or Se triode front end,simplicity rules the grado roost mostly until I hear better. You need to think in terms of 200-250 ma drive current and that must be class-a drive if the goal is a diffuse and spacious sound field from the RS-1 cans. Easy to drive straight out of any headphone jack they are plugged into,not so easy to get full performance capabilities from....

Thanks Rick,

I believe this information will be a valuable help for finding the right amp.

200-250 mA class A drive current won't be cheap, even in a DIY amp. oouuch

BTW: The Lehmann Black Cube has 400 mA output current at 32 Ohms, the CEC HD53 380 mA, edit: both not single-ended pure Class A.