[tourmaline]

Modding the bada to the max.

Here you will read and see pictures of the complete transformation of the bada headphone amp.

One of the problems of the bada is heat and some bad signal caps in the signal path, so i started discussing mods for the bada with some bada ownwers and especially with black stuart.

Part of the problems for the mods are chassis space, the bada is small and tight and the quality of components.

I opted to go all the way, to tackle the heat problem take all the "bad" parts out of the signal way or replace them by better ones and take the bada to a next level. In fact, it's not the next level, but several levels above the standard bada! The detail and natural sound is increadable.

let me walk you trought the several steps of the modification:

first step was drilling the bada bottom plate with big holes for heat dissapation; it didn't have the result i was hoping for.

The first step of modification i did myself. I knew talking to black stuart alot that the solen caps were "bad" in the signal path, so the first step was to take out the coupler caps and replace them with much better caps.

My local store makes alot of custom made components, like potmeters, transformers and silver signal plate caps. So, i opted for those silver signal caps to use for couplers, since they told me they were fantastic and a big step above the notoriously expensive audio note silver caps. They are square, so don't have the normal distortion found in round caps!

While i was preparing the bada for the modification, i took advantage and drilled the chassis with holes for heat dissapation. As you can see below.

Next step was to assemble the components needed for the first step of the mod;

custom made linear potmeter(much, much better then the alps blue pot). It's like not there in the signal path!

the caps, black gate and the silver signal caps and the tantalum resistors.

This was the first step and after soldering in the components and turning on the bada, i only had one channel! So, at first i thought i might have blown a fet, but it turned out to be a loose resistor. I went off to the shop for repair and i discussed with them to finish the total modification and finish what i started.

The second part is the complete mod of the bada, including powersection etc.

just as a reminder:
a picture of the pcb as it looked before the modification.

A big problem was to find replacement caps for the solen's in the signal path! The chassis is soo tight that most bigger caps of the value needed don't fit. So, i had to search for a capacitor that matched the quality of the silver signal plate caps and fit into the bada chassis. No small task, i can tell you.

After roaming the www, i came across the vcap capacitors. The vcap oimp cap looked just like the cap i need for quality and size!

beneath you'll find the pictures as the bada looks now after the complete transformation:

the drilled chassis, with the removed transformer to minimize fibration and give the mosfets more space to breath and dissapate the heat much better. On top is the aluminum chassis for the custom linear potmeter.

close up of the transformer and the feet:

overlooking the chassis and the complete transformation.

beneath the picture of the powersection:
note that the 4 resistors have been replaced by one large resistor for heat dissapation and i used longer screws and spacers for the mosfets to secure the mosfets very tight to the bada chassis for better heat dissapation. If they would come loose, wich could with the normal screw used in the bada, the mosfets could burn!

picture of the powersection of the amp:

the silver signal coupler caps, the cvap oimp and the black gate caps in place:

and finally the tube section:

meanwhile i was waiting for the local shop to finish the mod, i went ahead with the next step of cooling:

I constructed myself a chassis for the 2 x 12 cm papst fans, wich run on a seperate 12 volts converter. Advanatage of papst fans are: quality(they are the best around), sound production and they can be run from 7 volts to 12 volts. So, i can fine tune the soundproduction/airflow ratio to my liking. The choice for such huge fans is quite obvious: larger fans make less noise while keeping a better airflow ratio. In other words, at lower roation speed a 12 cm fan can move more air then a smaller one and will produce therefor less sound and cool better!

beneath a picture of the final result:

and the fans spinning:

The result of actively cooling the bada is that the bada is totally cool to the touch even after 3 hours of operation. Before, the bada was allready getting very, very hot(50-60 degrees celcius) after 1 hour!

The advantage is cool mosfets(better performance out of the fets, the cooler the better), cool tubes, so the life of the tubes is longer.


There you go, all the eyecandy you need for a well modded bada.

Personally i think my local shop did a great job modding the bada!
Also their custom made components are outstanding!
I also like to thank black stuart for advice and providing me the spikes i needed and drarthurwells for pointing me to the bada and beeing enthousiastic!

And for the sound:

while it is still not completely broken in: the vcap oimps take about 500! hours to completely break in, the sound is breathtaking! Detailed, natural, fast, clear, everything you want in a first class amp. It got all the goods and then some. It reminds me of the exotic very expensive amps. The headphone completely dissapears and music flows.

Some say the sennheiser hd 650 is veiled, with the modded bada: wich veil? it's completely transparent but the background is completely black! The sennheiser hd650 is slow: really? with the modded bada the sennheiser is fast, has drive and is musical!

If you want it all, go the path i took, if you want to make improvements on a smaller scale, take at least care of the solen caps in the signal path and replace the 4 parallel resistors near the fets to tackle a bit of the heat problems. The sound will benefit hugely.

Regards,
tourmaline.

For questions about components or anything you can contact me via PM!


If you wanna mod the bada or any other amp, you have to hurry since all the good quality components dry up fast!
Black gate stopped production of their increadable caps, Elna also, only some types of cerafines left and the prices go up and up for the good quality components as with good NOS tubes!

 

[mrarroyo]

That was some amazing work. I can not wait until you post a picture of the completed and fully assembled amp.

 

[Black Stuart]

Tourmaline,
I think you need to post a follow-up to this latest excellant and so nec. illustrated post with one about the values changed especially the 1uF caps changed for .47uF etc.

Some of the changes Roam talked of could usefully be exploited but they got lost in amongst his rhetoric.

I think Tourmaline's use of the Papst fans is groundbreaking and not just for the Bada - heat seriously alters the operating parameters of components and shortens their life considerably. I live behind the Sierras in Andalucia and the temperature yesterday was 41C/105.8F, the temp. inside apartments here (crap built) is normally 83F/25C and I will not use my valve amps in this kind of temp.

It would be interesting to see if using the Papst fans without drilling the chassis but removing the bottom plate is as effective - quien saves?

The Vcaps are expensive and from a friend who uses the Teflon version from venHaus and who also previously used Dynamicaps, rates the Dynos as only just behind the Vcaps.

Much to discuss in a positive way here, so input from all is required especially questions which may open new doors and alert us to new opps.

 

[tourmaline]

Quote:

Originally Posted by Black Stuart /img/forum/go_quote.gif Tourmaline, I think you need to post a follow-up to this latest excellant and so nec. illustrated post with one about the values changed especially the 1uF caps changed for .47uF etc. Some of the changes Roam talked of could usefully be exploited but they got lost in amongst his rhetoric. I think Tourmaline's use of the Papst fans is groundbreaking and not just for the Bada - heat seriously alters the operating parameters of components and shortens their life considerably. I live behind the Sierras in Andalucia and the temperature yesterday was 41C/105.8F, the temp. inside apartments here (crap built) is normally 83F/25C and I will not use my valve amps in this kind of temp. It would be interesting to see if using the Papst fans without drilling the chassis but removing the bottom plate is as effective - quien saves? The Vcaps are expensive and from a friend who uses the Teflon version from venHaus and who also previously used Dynamicaps, rates the Dynos as only just behind the Vcaps. Much to discuss in a positive way here, so input from all is required especially questions which may open new doors and alert us to new opps.

Hi Stuart,

i will make a follow up of things changed i know the values off. So much was changed, especially alot of resistors near the tubes that i dunno what was used.

The resistors is a good thing to change, especially the 2 in the signal path, but the biggest changes will be heard changing caps in the powersection, powersection of the output stage of the amp and the tubes.


I know your problem. Also in my house if it gets hot outside, the temperature inside gets hot quickly. Sometimes between 25-30 degrees celsius!

I read on the web that an increase of temperature of 10 degrees celsius will shorten the life expectancy of electrical components by half!!! This true for cpu, and any other component like resistors, caps etc.

So, obviously cooling is of essence, especially with mosfets and tubes, since they get very hot. This explains most of the very high cost of high end amps, since good cooling is expensive! 3Imagine the cooling needed for 100 watts class A!

 

[XenatR]

Quote:

Originally Posted by tourmaline /img/forum/go_quote.gif Advanatage of papst fans are: quality(they are the best around)

lmao who told you that... the best are the 12x2 Silverstones, which push 110cfm. they are quieter and more powerful than the papst.

 

[tourmaline]

Quote:

Originally Posted by XenatR /img/forum/go_quote.gif lmao who told you that... the best are the 12x2 Silverstones, which push 110cfm. they are quieter and more powerful than the papst.

LMAO: IF YOU think so.

According to my information the silverstone produces 42 db.

 

[tbonner1]

Nice work. No money was spared in the execution of these mods.

This is probably the best Bada in the known world.

Please keep us posted.

 

[tourmaline]

Quote:

Originally Posted by tbonner1 /img/forum/go_quote.gif Nice work. No money was spared in the execution of these mods. This is probably the best Bada in the known world. Please keep us posted.

Thanks for the kind words.
I don't know but it sounds allready pretty good to me. Yet, i have still alot of hours to go....the silver signal caps and especially the vcaps need a long time to fully show their potential. But all i can say allready is this: with my cheap cdp, i allready hear twice as much detail as i did before and it will get even better. During this week i'll get a new cdp as well, so then i'll know what this baby can do.

For the first time i got the feeling that the hd650 is the weaker part of the system. I got the feeling the bada is that good right now and the hd650 can't keep up. it is really obvious now in complex music that the hd650 smears sounds a bit. Ohwell, lets see what 2008 brings, apperently a new higher end sennheiser, hopefully a dynamic one. Otherwise an AKG 701 could be a good contender or a r10.

 

[Black Stuart]

Tourmaline,
slow down man - let all those caps burn in and then think about getting new cans.

I changed out a very important pair of caps in my phono stage for Dynamicaps and was underwhelmed for many months with the sound - it was'nt bad but lacked definition and weight.

Then one day I fired up and put on a record and WOW it was all there. The bass bloom that many mention re. the Senn 650s' is rubbish BUT I did buy after market cables and I did change caps in the Bada - voila no bloom.

Time to give us the gen. on the changed cap and resistor values Tourmaline. Any you don't know the shop will.

Could you also supply the precise Papst info and I will look to buy here in Spain - if others only do this mod, it wil show just how much heat does change sonics.

 

[tourmaline]

Quote:

Originally Posted by Black Stuart /img/forum/go_quote.gif Tourmaline, slow down man - let all those caps burn in and then think about getting new cans. I changed out a very important pair of caps in my phono stage for Dynamicaps and was underwhelmed for many months with the sound - it was'nt bad but lacked definition and weight. Then one day I fired up and put on a record and WOW it was all there. The bass bloom that many mention re. the Senn 650s' is rubbish BUT I did buy after market cables and I did change caps in the Bada - voila no bloom. Time to give us the gen. on the changed cap and resistor values Tourmaline. Any you don't know the shop will. Could you also supply the precise Papst info and I will look to buy here in Spain - if others only do this mod, it wil show just how much heat does change sonics.

I can give ya the info on the most important parts. Anyway, according to them the resistors give the least improvement, compared to the things changed. The change of the 4 resistors to another large wirewound one is mostly for heat dissapation. On some parts, the info was filed off. They do that over here all the time to protect the intellectual rights of their mods! So, even if i wanted to, i can't give ya all the info to do a complete mod as it was done with my bada.

If you can't find the right papst fans Stuart, i can order them for ya and send them to ya. I'll send the info to ya via email.

My new cdplayer came in today.
It's much more musical then the teac and extracts more detail as well. I still think the hd650 is not as good as some top headphones like the r10 or maybe even the akg 701.

The better things get, like the amp and the source, the more obvious problems with the hd650 become and it is general knowledge that the hd650 smears sounds in complex music. The akg is much better in that respect. Art(drarturwells) changed for that reason from the hd650 to the akg701, wich is according to him more accurate and has more air between the instruments/voices. What the akg701 lacks is musicallity, compared to the hd650.

The bada is very accurate, but the weaknesses of the hd650 become more obvious. I might wait till the new higher end sennheiser will be annouced in 2008. I even feel the highs and the stage of the hd600 were better!

Maybe time for a good aftermarket cable, but, i know a new sennheiser is comming so.........

 

[Black Stuart]

Tourmaline,
if your only using the stock Senn cable you are missing an awful lot. I have Senn 600s as well - there is no comparison betwen the two, once good aftermarket cables are used.

Back on topic - yesterday I was sitting at the bench looking at the Bada with the bottom plate removed, some thoughts;

Long signal cables trailing across the PCB are not a good idea, they are very well sheilded and this in itself I don't like. Why companies don't site the pot/volume control at the back using an extension rod to operate them is beyond me. If you look at a lot of amp designs from the 50/60s' you see lots of input/ouput connections on the side of the chassis precisely to acheive much shorter sig/wire runs. Some Chinese cos. adopted this sensible idea, yes I know this can create problems with space on a rack but it is always true that form should follow function.

With the Bada bottom plate removed and the front end nearest, there is room on the left hand side panel to site the RCA input sockets - better yet do away with the sockets alltogether and solder your I/Cs directly to the pot, using some form of strain relief on the incoming sig/wires.

Chassis wiring used - is solid core for signal/return and stranded for earth. the s/core looks to be silver plated copper and gauge approx 20AWG. I think the gauge is a bit much, I like what Dennis Boyle of Chimera Labs says about sig/wire - 24/26 gauge is about right, it's surprising how different gauges seriously affect sonics.

I would be happier with sheilded earth wiring but would never use this for signal, maybe Bada have done some research here and found as many do, that sheilding sig/wire does 'blur' the sound. So for me, it's only a question of gauge and wire quality that counts. When the PCB comes out for component changes, I will change the wiring to reflect my comments above.

The RCA sockets look decent enough but the amount of solder used is far too much. I shall replace them with some quality s/plated ones instead.

Tourmaline - am I right in thinking that the mains TX is only secured by the one visible screw? If so if there is enough play in the existing wiring then I may try to 'lift' the Tx and sit it on some small feet, this will be sufficient to allow heat dissipation from the mosfets underneath. Indeed hav'nt you used 3 small conical feet for your Tx - could you post on this point as I think they would be fine for what I intend to do.

I can't see a good reason to have built the PSU section horizontally, except maybe for the trailing incoming sig/wire and perhaps for clearance for the Tx wiring. If as I intend to remove the bottom plate altogether, the PSU PCB can be fixed horizontally to allow much bigger caps to be used here and on the main PCB as well.

 

[tourmaline]

Quote:

Originally Posted by Black Stuart /img/forum/go_quote.gif Tourmaline, if your only using the stock Senn cable you are missing an awful lot. I have Senn 600s as well - there is no comparison betwen the two, once good aftermarket cables are used. Back on topic - yesterday I was sitting at the bench looking at the Bada with the bottom plate removed, some thoughts; Long signal cables trailing across the PCB are not a good idea, they are very well sheilded and this in itself I don't like. Why companies don't site the pot/volume control at the back using an extension rod to operate them is beyond me. If you look at a lot of amp designs from the 50/60s' you see lots of input/ouput connections on the side of the chassis precisely to acheive much shorter sig/wire runs. Some Chinese cos. adopted this sensible idea, yes I know this can create problems with space on a rack but it is always true that form should follow function. With the Bada bottom plate removed and the front end nearest, there is room on the left hand side panel to site the RCA input sockets - better yet do away with the sockets alltogether and solder your I/Cs directly to the pot, using some form of strain relief on the incoming sig/wires. Chassis wiring used - is solid core for signal/return and stranded for earth. the s/core looks to be silver plated copper and gauge approx 20AWG. I think the gauge is a bit much, I like what Dennis Boyle of Chimera Labs says about sig/wire - 24/26 gauge is about right, it's surprising how different gauges seriously affect sonics. I would be happier with sheilded earth wiring but would never use this for signal, maybe Bada have done some research here and found as many do, that sheilding sig/wire does 'blur' the sound. So for me, it's only a question of gauge and wire quality that counts. When the PCB comes out for component changes, I will change the wiring to reflect my comments above. The RCA sockets look decent enough but the amount of solder used is far too much. I shall replace them with some quality s/plated ones instead. Tourmaline - am I right in thinking that the mains TX is only secured by the one visible screw? If so if there is enough play in the existing wiring then I may try to 'lift' the Tx and sit it on some small feet, this will be sufficient to allow heat dissipation from the mosfets underneath. Indeed hav'nt you used 3 small conical feet for your Tx - could you post on this point as I think they would be fine for what I intend to do. I can't see a good reason to have built the PSU section horizontally, except maybe for the trailing incoming sig/wire and perhaps for clearance for the Tx wiring. If as I intend to remove the bottom plate altogether, the PSU PCB can be fixed horizontally to allow much bigger caps to be used here and on the main PCB as well.

Good point, i have thought about it since my hd600 sounded much better with an aftermarket cable. I think it sounded better then the hd650 now with stock cable. But, and here it comes, we all know now that a series of new headphones is comming in 2008 from sennheiser, ranging from mids 500 to 1000 euro's for the top end. A good aftermarket cable will set you back at least 250-300 euro's incl. shipping. A good chance the new top of the line sennheiser is a good deal better then a hd650 with expensive aftermarket cable. Dilemma, invest 300 euro's now or wait a few months and see what the new senns do?!

Stuart, in this case the cables aren't that long. I used pure silver wire, specially designed for signals. I don't think it would a big deal if it was 5 cm shorter. There is a general equation that says that 1:4 can't be heard. it is used to calculate runs of speaker cable for your setup. So, this equation tells us that a 1:4 ratio cannot be heard and don't give any alteration in sound. it means if 1 cm is used another channel could use 4 cm before negative influence could be noticed.

As you know, i experimented alot with earth wiring and shielding; last night, i removed all earth wire from my cables and filters as well. I got much better channel seperation. Shielding makes cables sound dark and blurr details. I would use as less shielding as possible.

You know the guys at the shop who did the mod have self constructed IC's and they use only 1 very thin! copper or silver wire without any shielding. It looks alot like the audio note silver signal cable though. They used it to let me hear the modded bada and frankly, it didn't sound bad at all! So, clearly everybody knows(should know) that shielding in general is a bad thing!
For cables i don't like it at all.

Yeah, change the rca sockets, they won't cost ya much but there's still a bit to gain!

No, if i recall correctly, the TX is screwed on with 2 screws. 1 very thick and large and a smaller 1 as well, in my tx there's 2 screw holes...look at the pics above!

I will post a picture of the definitive setup as it is currently running. Then you'll see how i tackled the cooling problem and the problem with the spikes as well.

The problem is that the bada feet are attached to the bottom plate. I tried to put the bada chassis onto a spike point but that was way to wobbly. It is now fibration free and stable!

The silver signal wire i use is made of 20 very fine pure silver strands and sounds fantastic. 24/26 awg sounds a bit thick to me. it sounds lifelike and very clean. it's their favourite mod cable for internal signal wiring! Expensive, yes, but worth the money.

As you can see on the picture, it is very thin!

If anyone needs specifics about the mod, you can contact me via PM.

 

[Black Stuart]

WHOOPS,
renag, renag - I got it wrong and no I had'nt been imbibing or doing anything else.

The sig/wire is solid core copper, probably 0.7mm/21AWG or thereabouts. Also there is no sheilding on the incoming sig/wire. I would'nt have known if I had'nt cut away the heatshrink on one end.This for me is good news as I don't like sheilding per se on signal wire anyway. I have no idea how good this copper wire is or is'nt. I shall be replacing this and the wire from the pot to PCB with mil. spec. s/plated solid core copper - this is a personal choice and others may well differ.

This also means that you can replicate the wire configuration of your favourite I/C inside the amp, the outer red sheath is worth keeping and may have been used to sheild the sig/wires from vibration within the amp as well as protecting them from heat.

I don't know if Tourmaline has replaced any of this sig/wire or not. I suggest if you are going to change this, do so before changing caps - there is no need to lift out the PCB to effect this.

So for those who are thinking of modding the Bada do think carefully about all the sig/wire, changing this wire is no big deal.

I don't like the RCA sockets and using the plug body to solder the return wires to is not a good idea, much better is a dedicated earth tag, which the s/plated plugs I am replacing them with has.

Tourmaline - if this shop you used for the mods will not tell you the resistor values just use an online resistor chart to determine these and get back to us.

Personally if I paid serious money for these mods, I would insist on them telling me the values ( it's called making them an offer they can't refuse).

The resistor replacing the set of 4 next to the mosfets should be easy to read, it's almost certainly available from RS. I'm particularly interested in resistor values if they have been changed around the valves.

I will report back when I have changed the wiring.

Don't forget that shunting the pot is so simple and you can experiment to your heart's content with resistor types - I am going to try some Welwyn 1% 1/4W today but many may rec. Vishay bulk foil - big wattage is'nt important here, most stepped att. are built using 1/4W.

 

[tbonner1]

I find the Senn 650 to have good synergy with the Bada. The AKG 701's work well with a warmer tubey sound in the midrange and treble and like tubes that help make the bass more full.

 

[tourmaline]

Quote:

Originally Posted by tbonner1 /img/forum/go_quote.gif I find the Senn 650 to have good synergy with the Bada. The AKG 701's work well with a warmer tubey sound in the midrange and treble and like tubes that help make the bass more full.

Thanks tbonner1. it's not that the sennheiser is so bad or anything but i just have the feeling it could be even a bit better. I clearly hear the sounds smear when it gets very complex and i listen to any kind of music. Also pop etc, wich can get quite complex as well. But it allready is much, much better then it was since seperation and pinpoint accuracy is allready taken 2 steps up.

Tbonner1, i would urge you to replace at least some basic components for better ones, it gives you even more fun listening to the bada! It won't spring the bank, since you can determin yourself wich stuff you wanna use.

The bada has so much power now, i could blow up the hd650.LOL.