[drarthurwells]

Tubes make a big difference.

Changing tubes in the Bada can be like changing amps.

Here is one email I got today from someone who switched to one of the three "gold standard" tube combos I list on page 5 of this thread:

From : @yahoo.com
Sent : Saturday, April 14, 2007 2:45 PM
To : Arthur Wells <drarthurwells@hotmail.com>
Subject : RE: The "Dr. Arthur Wells Inspired Headphone Enjoyment System"



Greetings Art,

I received your box on Friday, inserted the tubes as instructed, turned on the Bada to warm up for 30 min., then settled in to listen. My goodness...I had one of those "A'ha, so that's what I've been missing out on!" moments. I'm not that familiar (as you are) with the lexicon of proper adjectives to match sounds, but I will try. I perceived an aural dimension of richness and improved overall clarity and impact. And that of course was only in comparison to the first combo you sent me, which up to now was all I had. You have saved me much trial and error research by your valid recommendation, and I would go as far to say that the two Sylvania W output and RCA black glass should be standard reference for anyone who owns the Bada, otherwise they would be missing out. (By the way, I still owe you money for the RCA tube which you so wisely included in the box). Also, on some better recordings, for the first time I am able to detect a (3-D?) placement of musicians playing that I never knew was possible...that is surely attributable to the tubes/synergy/combo that you've hand picked.

This type of improved listening experience reminds me of only time I upgraded from Wireworld IC's to a then new copper interconnect from Outlaw Audio. Wow! is easily the most accurate description of the improved change in hearing so much more music come through. Your suggested tube change combo is no small , subtle improvement. I think it is an esential dynamic part of an overall "best bang for the buck" headphone/amp system. I know now that my personal listening enjoyment has been enhanced thanks to you.

END

Name withheld to protect privacy - will put anyone in contact with this party by their agreement.

 

[Dan the man]

Has anyone compared the Bada PH-12 tube headphone amp to the Woo Audio w6 or the DOGE 6210 EL84 Headphone Amplifier?

 

[tbonner1]

Bada PH12 and Doge reviewed here:

http://www.head-fi.org/forums/showth...20#post2805020

Yarland P100 scheduled for review

 

[zheka]

hello

had anybody tried ultrasone proline 'phones with Bada?

i understand Bada is not good match with grados. i wonder if that holds true for ultrasones which are also low impedance - 40 Ohm i believe

thank you

 

[Karkass]

wow .. 1 EH goldpins with 2 raytheon GT are.. just too good with the bada..
sounds perfect !!

 

[pataburd]

Quote:

Originally Posted by zheka /img/forum/go_quote.gif hello had anybody tried ultrasone proline 'phones with Bada? i understand Bada is not good match with grados. i wonder if that holds true for ultrasones which are also low impedance - 40 Ohm i believe thank you

Bada PH-12 + Ultrasone Proline 2500/750 = LOVE!!!

The two match exceptionally well, IMHO. See my brief comments on the dedicated 2500 thread. I ran the Bada w/1x 6SN7EH gold pin and 2x Raytheon VT-231. In short, the best the Ultrasones have sounded to my ears to date. : )

 

[pataburd]

After listening to the (hybrid) Bada for about a week, having purchased it used and fully broken in, I've begun some cursory a/b-ing between it and the (all tube) Darkvoice 336i. Both amps use the 6SN7 tube in the input stage, while the Bada uses two more 6SN7s for driving, and the Darkvoice a single 6AS7.

Admittedly, I've developed a lengthy attachment to the 336i, which I've owned for 9 months now and to which I have listened regularly over that duration. The Darkvoice, having survived the Meier Headfive, Dynahi Veda-SA and G&W T-2.6F over its abbreviated tenure, now finds itself alongside the well-published Bada PH-12.

These first impressions are based on the Darkvoice in my home system (Panasonic S47 player/MAC Silver Braided IC, MAC Source and MAC HC PCs) and the Bada in my office system (RAM-modded Samsung HD-841 player/MAC Palladium IC, MAC Source and MAC HC PCs). The Ultrasone Proline 750 were used in both systems. The Darkvoice was tubed w/1x GE 6SN7GTA & 1x JAN-CRC (RCA) 6AS7G; the Bada w/1x National Union 6SN7GT & 2x RCA 6SN7GTB (older style). So, in some sense, it might be argued that the Bada was given favored source and cable status. In defense of the (stock) S47, it is a very musical, budget over-achiever in its own right.

The biggest difference noted so far is that the Darkvoice is a bit smackier and more tonally focused than the Bada, due perhaps to the 6AS7 driver tube. That said, the PH-12's presentation is more expansive, smoother and renders more ease of detail, although not necessarily quantitatively more detail, compared with the 336i. The Bada's soundstage is laid out very well, with precise discrimination of individual instruments/performers in space and with a heightened perception of "air" inbetween. Bass is deeper, more pervasive and better articulated with the Bada as well, although not as punchy as the Darkvoice. I will also volunteer that the Darkvoice is perhaps seasoned a bit more sweetly and the Bada a bit more neutrally.

Earl Thomas Conley, Greatest Hits Vol. II, and Michael Jackson, Off The Wall (re-master). Both of these recordings stray toward the bright side. Vocals were more open and airy with the Bada. Bass was more foundational and easier to follow, too. The Darkvoice does lend an elusive breadth, sweetness and integrity to vocals and instrumentals, though. The "Bada sound" is certainly the more transparent of the two offerings, but the Darkvoice has a pleasant "spryness," vividness and relief to it that can be more attention-getting than the Bada.

If the Darkvoice is a sponge somewhat sweetly dampened with music, then the Bada is that same sponge, only fully saturated and uniformly swollen with more of that same, albeit slightly more neutrally and less impactfully vintaged, music.

So, do I like the Bada? (Oh, yes!) The next step will be to bring the Darkvoice to the office and hook it up to the same source/cables as the Bada.

Preliminary verdict: "The Bada is very Gooda!" But betta than the Darkvoice? The "if" and "how" of that question remain to be answered. : )

More to follow . . . God willing, next week (with the HD650 and K701 scheduled to arrive, too!).

 

[pataburd]

Hooked up the HD650/Revelation Audio Labs Silver Reference to the Bada, switched to "high impedance," w/1x RCA 6SN7 gray glass and 2x 6SN7EH (non-gold pin). The sound is excellent, much smoother than with the Proline 750 (w/Bada switched to "low impedance"). The RAL cable makes the HD650 sound much more detailed and immediate, and lifts the Sennheiser "veil."

With the Proline, the sound is edgy by comparison. When I first auditioned the Bada/750 combination, I had only Ultrasone headphones on hand. Now I am begining to think that the "low impedance issue" does come into play with the Proline.

I would be interested in knowing what amplifiers Proline users are running with their headphones.

 

[Black Stuart]

Pataburd,
the Bada in it's original form is IMHO no great shakes. With some modifying it's excellant.

This amp is full of Solens, in the PSU maybe they are acceptable but anywhere in the signal path they are CRAP - cold dull and lifeless, so if you are enjoying it now just think what a little work will do.

Take the supplied power cord and do what you like with it - stripped down to it's individual wires, they are good for tying things together if you have a garden but don't use it for the Bada.

If you take a look at the photos supplied by Art on page 3 of this thread you will see just to the left of the output valves a Solen 1uF x 250V cap - these are real crap and are sitting on the sound. I have used Mundorf Audiophiler caps here which really lift the sound but I am about to fit Dynamicaps here, which I have used in my valve phono stage, these are very good indeed but just today from a Dutch friend I have found out that Solen are introducing a Teflon cap which they rate just behind the fabulousy expensive Ven haus Teflon cap.

On the right hand side of the two output valves there are Solen 2.2uF x 250 caps here - again these are crap, I have used Audiophilers here as well. Take note that whatever caps you replace you will have to fit them inside a very small space.

Changing out these two pairs of caps will make a huge difference to the sound. There are other caps I would like to replace but lack of space is a big problem.

Looking at the photo on page 3 again, just to the right of and between the 2.2uF Caps are two resistors. As you can clearly see from the photo they are becoming discloured, Replace these with at least 5W resistors of the same value, I think it is 15K but check to make sure.

To change the caps and resistors I have rec. you do not need to remove the PCB, just cut off the legs as close to the body of the caps and resistors as possible and solder to these existing legs - one day when you are satisfied with all the changes you have made is the time to remove the PCB and fit the new caps properly - you will here no difference in sound but it looks better.

Another change I would rec. but which can be reversed easily is to 'shunt the pot' - all this means is that the Left and Right output wires from the Alps potentiometer are cut about 1inch from the PCB and you solder in a resistor ( anywhere between 47-68K) in series (that just means in line). Anything from 1/2W up is fine. choose a good quality one Tantalum, Shinko, Dale,Vishay.

By doing this you are to all intent shunting or moving the pot out of the audio signal. You will lose some volume by doing this, which means you have to turn the volume control up some to acheive your normal listening level. This is so simple to do and if you don't like it, desolder the two resistors and resolder the two sections of wire back together

Tube rolling - where mosfets are concerned this is a bummer as you need to wait at least 12 hours before changing a valve, that is unless you get off on replacing mosfets and all the work that entails - we have Art to thank for this info.

My following comments are made for the Bada PH12 with the clear understanding that my model is no longer standard and is run using a power cord made from mil. spec s/plated copper wire (Rechem), a shunted pot (Dale resistor) and two sets of caps changed for Mundorf Audiophilers:

Shuguang 6SN7 - I believe that if the Chinese really went to town on this valve they would have an a runaway winner on their hands. It is crystal clear and used as the driver valve with the right o/put valves will give the NOS a real fight.

It has for me only one fault which maybe is not the same for all of those produced - it loses it when their is an uplift in the music or a singer raises his/her voice right at the top but in all other respects it is just superbly clear, all instruments are defined so well. I use it with NOS Sylvania WGTA.

When I first used this combo I was shocked as it changed dramatically music I know so well. It also shows just how much detail is lost behind hash from many so called top class I/Cs - I use a special format for my I/Cs.

I have tried other combos but they just present music as a kind of one dimensional field with all this background hash. At first the word 'stark' came to mind but it is'nt - it's what the recording engineer heard being recorded.

For all those who think that all cables sound the same - please go away and play somewhere else. Use this combo to listen to your I/Cs - a good I/C wil not get in the way at all - percussion is so good, so clear, bass should be well defined and truly extended, piano is something special and electric guitar just comes out at you, like it does at a gig. This combo will show it like it is - good, bad or indifferent.

If you bought the Bada from new you probably have these Shuguang valves and a pair of used Syl WGTAs should'nt cost a lot. Also try the Syls with an EH - which I know a lot of us have.

It really is true with the Bada, that with a few judicious changes of components and the mix of valves is just right - it's wonderful.

 

[pataburd]

Black Stuart,

Thank you very much for the excellent advice. I did replace the stock power cord with the MAC Source pc, to significantly postive effect.

As to the balance of your suggestions, my DIY skills are at a dearth here. Perhaps with some mentoring and further encouragment, I shall gather the replacement parts, print your instructions and Art's picture and--by the grace of God--get this project underway. If you have pictures of the specific mods you did on your unit, and which are described in your post, they would be of inestimable value as well.

Right now I'm running 1x Toshiba 6SN7GTB w/2x RCA 6SN7GT black glass. The Proline 750 are really singing well as-is; it would be a treat to hear even better from the Bada!

Thanks again!
Patrick

 

[Roam]

The problem with the capacitor swaps and other mods listed to date is that they're the proverbial band-aid on a broken leg with multiple compound fractures. They don't fix anything except on a superficial surface level.

Bada PH12 schematics. First change, the 10k plate resistors (R13, R16)for the cascode gain stages should be upped to at least 33k, preferable around 40-50k. This will greatly linearize the tubes and significantly lower the distortion along with raising the gain. Also drops the current going through them, reducing heat and extending tube life.

Next, the grid leak resistor on the 2nd stage of the cascode (R15) can be bumped up to around 300k, and the coupling capacitor between the cascode stages (C21) can be reduced to 0.22uF. Smaller caps sound better, and you have a better choice of caps at the smaller size. Teflon exotics are now in the mix if you want them.

Now, remove the 2.2uF coupling cap (C22) between the cathode follower and MOSFET output stage and replace it with the 1uF unit you've removed in the previous step. Not as significant as the other improvements, but it will give slightly better sound.

I'd consider all the above steps as mandatory in fixing the circuit from "incompetantly designed piece of crap" to something which meets minimal acceptable standards.

The following step is optional, but it should also significantly improve the sound by further lowering the distortion and raising the linearity of the tubes. It also bumps up the gain a bit. Replace the cathode resistors on the cascode stage (R14, R17) with low brightness LEDs. Use 2 yellow LEDs in series to replace R14 and 3 red ones to replace R17.

This is about as far as it can be pushed without hacking up the PCB and completely redoing the circuit. It will now sound much better than stock.

 

[Black Stuart]

Roam,
so the Bada is an 'incompetently designed piece of crap' - strange that in a shoot-out it beat the likes of a Singlepower/Doge etc. so they must be -incompetently designed crap also.

To make these statements you must be one of the world's best amp designers - do let us know your real name and then we can check out your world beating designs.

Signal tubes in general do not generate a lot of heat and you hav'nt even mentioned the huge amount of heat generated by the mosfets - why not. If you have real experience, why hav'nt you addressed this issue, or at least pointed out that excessive heat will change operating parameters and values and most importantly of all - seriously shorten the life of the caps.

You also mentioned re-using a Solen cap why, these are cheap and nasty and sit on the sound, you drastically demand changing cap values which will change all the parameters and therefore the overall sound.

You hav'nt actually listened to a Bada PH12 have you - all your sweeping statements are based on theory. There are so many instances where 'in theory' something should'nt work but does.

All you've done is look at a schematic and make pronouncements. The suggestion of using LEDs may well be a good one but where are the suppliers and part nos.

So let's have your real name and the amps you have designed and then we can all make prononcements too.

 

[Roam]

Quote:

Originally Posted by Black Stuart /img/forum/go_quote.gif Roam, so the Bada is an 'incompetently designed piece of crap' - strange that in a shoot-out it beat the likes of a Singlepower/Doge etc. so they must be -incompetently designed crap also.

I honestly don't have the time nor inclination to read through every single shoot-out and comparison along with trying to determine the viewpoints & biases of those writing the reviews. I'll just have to take your word that people have indeed rated the Bada PH12 over the other amps and that their opinions are honest and pure as fresh fallen snow.

However, I do have the schematics for the Singlepower, Doge, and many other amps, and frankly they're nothing to write home about, and in the case of the Doge it's even more incompetant than the Bada.

Quote:

To make these statements you must be one of the world's best amp designers - do let us know your real name and then we can check out your world beating designs.

It does not take a world class designer to see the faults in the Bada & other amps, all of the design flaws are basic level fundamental screw-ups which even a neophyte can recognize after reading the first few chapters of Valve Amplifiers by Morgan Jones. It's not rocket science, it's basic tube theory.

Quote:

Signal tubes in general do not generate a lot of heat and you hav'nt even mentioned the huge amount of heat generated by the mosfets - why not. If you have real experience, why hav'nt you addressed this issue, or at least pointed out that excessive heat will change operating parameters and values and most importantly of all - seriously shorten the life of the caps.

MOSFETs sound best when they're run wide open, which of course creates a lot of heat. To me it's not a concern, there's only one of them per channel so if & when it fails, replacement is simple & cheap. If the life of the power supply capacitors is a concern, then simple use caps rated for 105°C.

Quote:

You also mentioned re-using a Solen cap why, these are cheap and nasty and sit on the sound, you drastically demand changing cap values which will change all the parameters and therefore the overall sound.

The suggestion to re-use the Solen cap was made with interest towards keeping costs down while improving sound, a freebie if you will. If cost isn't a concern then chuck it and use whatever fancy capacitor pleases you.

With regards to drastically changing cap values, I suggest familiarizing yourself with the simple formula F = 1/(2Pi * R * C) which determines the -3dB point of the bass roll-off. In the cascode stage, the -3dB point moves from 1.6Hz to 2.4Hz. This will have no effect on the circuit's performance, besides getting rid of the problems inherent with using an overly large cap, that being increased inductance, poorer overload recovery, greater leakage current, etc. The same applies to the coupling cap leading to the MOSFET, -3dB goes from about 1.5Hz to 3Hz, it's an inconsequential changes except for the superior properties of a smaller capacitor. This is all basic circuit design.

Quote:

You hav'nt actually listened to a Bada PH12 have you - all your sweeping statements are based on theory. There are so many instances where 'in theory' something should'nt work but does.

Actually, I have. The fact that I didn't kick it across the room in disgust is a testament to how forgiving tubes are of epic design failures.

Quote:

All you've done is look at a schematic and make pronouncements. The suggestion of using LEDs may well be a good one but where are the suppliers and part nos.

All you've done is make blind parts swaps with boutique brands in the hope that it'll improve the sound. You've failed to look at the circuit, understand the circuit, know what it does and what's going wrong, and then addressed the root cause of the problems.

Quote:

So let's have your real name and the amps you have designed and then we can all make prononcements too.

One of my designs is in the DIY forum. As for my real name, past experience with insecure deranged audio nuts has led to a policy of keeping it to myself. My wife does not care to find another envelope in the mail containing rambling incoherent threats against me.

 

[a-LeXx]

Roam,

you seem to know your stuff

One question, maybe you can help:
Do you know the G&W t-2.6f amp? The schematics have been available on internet, but I seem not to be able to find them any longer.

From what I remember from schematics, it's a 6dj8 SRPP with MOSFETs at output. Have no idea why the designer decided to use SRPP there, resulting in a gain of about 23-28 dB. No global feedback, if I remember correctly.

My issue - to much gain for 40-Ohm HPs. What would be your idea to lower gain? Some local feedback? Global feedback? An attenuator at the output of SRPP to MOSFETs?

Thanks,
Alex

 

[tourmaline]

Quote:

Originally Posted by Roam /img/forum/go_quote.gif I honestly don't have the time nor inclination to read through every single shoot-out and comparison along with trying to determine the viewpoints & biases of those writing the reviews. I'll just have to take your word that people have indeed rated the Bada PH12 over the other amps and that their opinions are honest and pure as fresh fallen snow. However, I do have the schematics for the Singlepower, Doge, and many other amps, and frankly they're nothing to write home about, and in the case of the Doge it's even more incompetant than the Bada. It does not take a world class designer to see the faults in the Bada & other amps, all of the design flaws are basic level fundamental screw-ups which even a neophyte can recognize after reading the first few chapters of Valve Amplifiers by Morgan Jones. It's not rocket science, it's basic tube theory. MOSFETs sound best when they're run wide open, which of course creates a lot of heat. To me it's not a concern, there's only one of them per channel so if & when it fails, replacement is simple & cheap. If the life of the power supply capacitors is a concern, then simple use caps rated for 105°C. The suggestion to re-use the Solen cap was made with interest towards keeping costs down while improving sound, a freebie if you will. If cost isn't a concern then chuck it and use whatever fancy capacitor pleases you. With regards to drastically changing cap values, I suggest familiarizing yourself with the simple formula F = 1/(2Pi * R * C) which determines the -3dB point of the bass roll-off. In the cascode stage, the -3dB point moves from 1.6Hz to 2.4Hz. This will have no effect on the circuit's performance, besides getting rid of the problems inherent with using an overly large cap, that being increased inductance, poorer overload recovery, greater leakage current, etc. The same applies to the coupling cap leading to the MOSFET, -3dB goes from about 1.5Hz to 3Hz, it's an inconsequential changes except for the superior properties of a smaller capacitor. This is all basic circuit design. Actually, I have. The fact that I didn't kick it across the room in disgust is a testament to how forgiving tubes are of epic design failures. All you've done is make blind parts swaps with boutique brands in the hope that it'll improve the sound. You've failed to look at the circuit, understand the circuit, know what it does and what's going wrong, and then addressed the root cause of the problems. One of my designs is in the DIY forum. As for my real name, past experience with insecure deranged audio nuts has led to a policy of keeping it to myself. My wife does not care to find another envelope in the mail containing rambling incoherent threats against me.

Sorry roam,but i agree with stuart on this one.Design doesn't tell you anything. it's all in the sound.

It's all too often that on paper something impressed and just sound bad! Happenend before!

I am the one that is turning the bada inside out and and when i am finished it's in another ballpark all together. Even the professional modders stated to me that they were pretty impressed by the sound and that says alot since they mod the most expensive amps on a daily bases with the most exotic components!

The re-use of the solens tell me that you really don't know anything at all. Everybody with basic knowledge of caps will tell you that solens are BAD for signal caps. They are ok in the powersection but you need to get rid of the solens as fast as you can out of the signal path!

I allready changed the solen couplers and the amp is in another league. You cannot even compare the two amp, the modded is like day and night. When i am finished, it's even like the earth and mars, so far are they apart!

Not to mention tuberolling. The best NOS tubes take the bada to the next level, put on top new signal caps, coupler caps and a complete modded powersection and you'll know they are nothing alike!Even a noob knows not to look at the specs on paper! But to listen to an amp. The bada is one of the most natural sounding amps. And i've owned much, much more expensive amps!

Again, people don't like the designs of say audio note in general, but they all love the sound and musicallity. Now what does that tell you?!Oh, and i did change the coupler cap for a smaller one.......I asked the professionals...they know what they are doing!Smaller caps combining, if you combine to bad caps to lift eachothers faults, you still gona have a bad cap. better use one superieur instead! or better, two superieur caps!

You can like the sound of an map or not, but please don't tell me it's a piece of crap. I had much more expensive pieces of crap. Not always the car with the biggest engine wins the race!

The bada won out of 20; this means it beats also more expensive american designs!