2BTL - My Audio Odyssey 2011 (Maybe into 2012!)

PreCd

As the title states my upgrade and mod to the SDA2Bs has been an odyssey and continues to be. It all started when my Yamaha R9 give up the ghost and I went hunting for more gear. I have loved audio since a kid but strayed from the fold years ago because I simply did not have a place to sit and enjoy my music. Well that changed, I bought some used power gear, and went to town on everything with new caps, etc....

I went with the 2BTL mod for the 2Bs but took a different approach. The House and Senate still sees fit not to straighten out the economy so I had to rein in a few cost items. In other words I did what they should be doing. Below is what they look like at this time (please don't bust my chops about the Erse metallized polypropylene film cap ok):

I purchased some metallized polypropylene film capacitors for the tweeter section and replaced the mid-section with the same electrolytics that were there, my budget cut. Took the bypass cap out and replaced the polyswitch. Listened for awhile and things sounded real good. Here is where my learning began. The change in sound was nice but the more I listened the less I liked what I was hearing. The highs were scratchy. So I removed the polyswitch and run the jumper between the leads. Fired it up. Not bad again but the more I listened the more I disliked things. Talked with F1nut about it and he suggested that I install a .5 ohm Mills capacitor there. which would smooth the highs out and replace the resistance the polyswitch put into the circuit. Did that and things got better and I liked that for a day or two. Let me say that the addition of the .5 ohm Mills really changed things. I believe I am able to hear the SDA affect much more now that the tweet is not drowning out some things. I am also able to hear more detail in the music. Still not happy though. I still have this scratchy sound at times in the speakers. Not often but with certain tones it shows up. And some of the music at higher levels meshes together rather than the instruments staying separate. I am sure it is there all the time but just more noticeable at a little higher level.

So now I am to the point of replacing the electrolytics in the mids with the metallized polypropylene film also. EVERYONE said I should have done this from the start but I wanted to see if it was nirvana on their part with these audio capacitors. It was not nirvana I can assure you. I learned a lot doing it my way but I would suggest you listen to them if you do not like to pull your speakers down to solder components on a bizzillion times.

I am now sitting here waiting on the new caps to show up. Just ordered them last night so I will not be able to hear them until next week probably. One other change that I might make after replacing the mid caps is in the .5 Mills resistor. I will wait until I get the new electrolytics out before I do though. My tweet is just a little to low now maybe. I am hoping that the metallized polypropylene film caps in the mid will take care of that as I believe I may get a little more high out of them when those go in. And more detail which may help my that small but annoying problem. If not I may go in and replace that .5 Mills with a little smaller Mills resistor. Again the .5 Mills really changed things and I was surprised to see that it made that much difference in the highs.

That is where I stand at this point. If you are new and doing an upgrade to your speakers you can listen to the folks here who make suggestions to you and save a lot of time. Or you may wade in and do it your way to only find that you will probably be doing that anyways! :eek: I have had good help here and I really appreciate those who have helped me with this, my 1st mod and upgrade.

inspiredsports

You're on the right track!

The only thing you might have missed from the body of knowledge written here at CP is that Sonicaps can take over 250 hours to settle down.

While the 5.8uf is only in your conour circuit, its newness could be causing some of your high-frequency dissatisfaction. You won't know for sure until you replace the 12uf Erse and then power them up for many, many hours.

PreCd

Did I mention I was using PulseX caps?
I know there has been discussion about using different caps together however I bought the 5.8uf cap and then realized that the Sonicaps were not funded by any government program. Not that I could get funding seeing that I work and am a U.S. citizen. Ok...I promise no more political jabs.

PreCd

I was looking over the pics of the mod to my SDA2Bs and things look strange. Looked over the schematics and it cleared things up a bit. I attached some pics so that you all could see what I was looking at. My speakers were originally SDA2As, were upgraded to SDA2Bs by the audio store in 1987 or so, and I just wanted to be sure we were looking at apples to apples here. Pics below.

Red Line = 5.8uf Sonicap
Yellow Line = 2.7 ohm Mills resistor
Maroon Line = 12uf, 20uf, and 40uf capacitor.

Please take a look and give me your feedback. I want to make sure I have everything in the proper places. I flipped the foil side horizontally so that it would be easier to follow the components on the board.

PreCd

After listening to my SDA2Bs with the Erse 12uf in the high and the Erse electrolytics in the mids I am changing the caps out. The 12uf Erse is getting replaced with a Sonicap Gen I and the electros with Solens.

Without gear to measure my setup I am going by ear alone and the highs seem gritty and harsh on some recordings. We will see if the change to the Erse 12uf takes care of that.

F1nut

The crossover pic looks right.

Remember, new caps take a couple of hundred hours to burn in.

PreCd

F1nut wrote: »

The crossover pic looks right.

Remember, new caps take a couple of hundred hours to burn in.

I remember. Looks like I am coming full circle to what you told me earlier in this project. And that was that I would not be satisfied with the electros and use Sonicaps at the least in my tweeter circuit. I believe all the way around was the suggestion. May end up doing that if the Solens don't work out in the mids. It is fun though and I have gotten a chance to hear how different components affect the sound.

I am nearing the point where I just want to sit back, pop a CD in, and enjoy the music though!

PreCd

PreCd wrote: »

Without gear to measure my setup I am going by ear alone and the highs seem gritty and harsh on some recordings. We will see if the change to the Erse 12uf takes care of that.

Meant to say "change to the Sonicap 12uf"

PreCd

I got my Solen Fast capacitors in today. Two 20uf and two 40uf caps. The 40uf caps are huge, 57x37mm. The rating on the cap says 40,00uf so when I first saw it I thought holy crap Madisound sent me 40,000uf caps?! Quickly I realized that a cap that big in a poly would not fit in my car. It is the French's way of writing 40.00uf. Measured them on a standard ohm meter and all read exactly the same so I am pleased so far. And Madisound was really good about shipping!

Monday the Sonicaps will be in for the tweeter and I can go to town on these puppies.........again.

drumminman

Cool :loneranger:

Remember what F1 said - caps do really take a while to settle. I heard changes in stages: at around 50 hours, 110 hours and around 200 hours.

It's all good. I'm betting you wind up replacing Solens with Sonicaps. You'll never know how good these can sound until you do, and it's only money :twisted:

PreCd

Ok. I replaced the 12uf Erse Pulse X with a Sonicap 12uf so now my tweeters are all Sonicaps. The 20uf and 40uf got some Solen Fast Caps. I will not comment on the sound yet as I have learned that different ain't necessarily better so I will listen for a few days before I comment.

When I did the original replacement of all the pieces, replacing like electros with electros; RDO-198s; notch filter; I also added a .5 ohm Mills resistor to calm the tweeters down a bit. Listened awhile and commented to Jesse that they sound very good now that the resistor was in. Well I changed the .5 Mills out with a .33 Mills tonight and I like it better.

One problem I have been chasing is noise in my left channel tweeter. When listening to nice soft music everything sounds great. When I listen to something a little more complicated with a lot of highs the tweeter just grinds on me. I have been doing everything to diagnose it but have yet to kill it. Switched tweeters. Re-soldered some stuff in the tweeter path. I thought the change from electros and Sonicap may cure it but nope. The .33 Mills seemed to have helped some but I just can't say yet.

Anyways listening to them now and will comment on them in a few days.

Joe08867

You have many hours before all the harshness disappears. I say the 200hr is the biggest change, after that the changes are minimal but discernible.

Give the crossovers some time to work in. Do not pass judgement until at least 100hrs. Make changes after that not before.

PreCd

Joe08867 wrote: »

You have many hours before all the harshness disappears. I say the 200hr is the biggest change, after that the changes are minimal but discernible.

Give the crossovers some time to work in. Do not pass judgement until at least 100hrs. Make changes after that not before.

I agree but this "harshness" has been there through the burn-in of the 1st round of changes and really started when the .5 Mills was added. Really harshness is putting it mildly. I was hoping converting to the Sonicap and Solen caps to replace the electros would take care of the harshness. When it did not I remembered that it really raised its head when I replaced the poly strap with the .5 Mills.

One thing I have noticed is that the Mills .5 resistors read .7 - .8 ohms on my meter. The .33's read .4-.5 ohms which is much closer to the polyswitch resistance. I cannot figure out why giving the tweeter more current reduced the "harshness" but it did.

So now I will let them burn in for the next couple of weeks. Again I do not want to speak to the changes at this time but I can tell a distinct difference between the electros vs. the Solen capacitors in the mids.

Phasewolf

How long did you use the Pulse x caps before you gave up on them? My friend used them and they sounded fairly good after 200 hours or so.

F1nut

PreCd wrote: »

I agree but this "harshness" has been there through the burn-in of the 1st round of changes and really started when the .5 Mills was added. Really harshness is putting it mildly. I was hoping converting to the Sonicap and Solen caps to replace the electros would take care of the harshness. When it did not I remembered that it really raised its head when I replaced the poly strap with the .5 Mills.

Kevin, you've got to slow down. You need to run them 24/7 for 8 days to reach 200 hours and I know you haven't done that. Stop making any changes until you get 200 hours logged.

That said, adding the .5 ohm resistor cannot make the highs harsher. You have to keep in mind that the caps can and will change, sometimes hourly, which is most likely the reason for the harshness and the changes in the harshness.

One thing I have noticed is that the Mills .5 resistors read .7 - .8 ohms on my meter. The .33's read .4-.5 ohms which is much closer to the polyswitch resistance. I cannot figure out why giving the tweeter more current reduced the "harshness" but it did.

I've never had a Mills that didn't measure dead on. Maybe your meter is off.

Phasewolf

Yes too me the meter sounds like it is off. For working with small values my friend has a really good meter with $200 dollar probes.

PreCd

Phasewolf wrote: »

How long did you use the Pulse x caps before you gave up on them? My friend used them and they sounded fairly good after 200 hours or so.

I had them in about that, maybe a little less but not much. I pretty much run the speakers all day for about 4 days and then a great deal for about 3 weeks. I really give everything with my 1st round of upgrade a chance. To be fair the Pulse X cap was only in the tweeter section with the 5.8uf Sonicap as the notch filter along with the electrolytics from Erse in the mids. I definitely did not like the direction my speakers were headed with that setup so I took the advice of many here and put Sonicaps in the tweeter section. Also replacing the mids with Solens which many advised using Sonicaps there also. Lets see how this setup goes after a few weeks.

PreCd

F1nut wrote: »

Kevin, you've got to slow down. You need to run them 24/7 for 8 days to reach 200 hours and I know you haven't done that. Stop making any changes until you get 200 hours logged.

That said, adding the .5 ohm resistor cannot make the highs harsher. You have to keep in mind that the caps can and will change, sometimes hourly, which is most likely the reason for the harshness and the changes in the harshness.

Slow my row! I have on yours and others advice.

The harshness was there with the last setup: Erse 12uf, .5Mills, Sonicap 5.8uf, 2.7Mills, Erse electrolytic 20uf and 40uf in the Mids. Around 200 hours on this setup it was getting worse so that is what prompted me to get off my wallet and upgrade the caps again. After that the same symptoms existed so I replaced that .5 resistor with the .33. It may have been a shot in the dark but it seemed the music sounded good at 1st with the .5Mills post Sonicaps but went downhill significantly in a few days. May have been I was only listening to easy music the 1st few days and when I switched to something more complicated it showed up. It seems to have gotten better but I need to do some critical listening to be sure. Also I have always liked Treble more in my music so I think the .33 works better for my ears.

As for the meter it could be in line for a battery change. I have a good one so I will do that and see what they measure.

As always thank you for your advice and expertise on this. I listen to you but also go off on my own way at times as it is my nature. Don't think I don't appreciate your advice.

Ok.....slowing my row and I promise NO CHANGES until after 200 hours if needed.

audiocr381ve

I've made plenty of changes to my 2BTL's, but have never encountered any harshness. Thinness, yea. But never harshness. I just swapped out all of my Sonicap's and Mills for Clarity Cap PX's and Mundorf 10 watt resistors and again, no harshness.

Something has gone wrong or maybe a change to your room would explain some things.

PreCd

audiocr381ve wrote: »

I've made plenty of changes to my 2BTL's, but have never encountered any harshness. Thinness, yea. But never harshness. I just swapped out all of my Sonicap's and Mills for Clarity Cap PX's and Mundorf 10 watt resistors and again, no harshness.

Something has gone wrong or maybe a change to your room would explain some things.

When I placed the notch filter on the boards I did notice that the solder pads had oxidized. Being new to all this I did not understand at that time that this could be a problem. The acid in the flux is supposed to take care of some of the oxidation but I do not think it eat through all that was on the board. I am going to let it run for a while under the current setup and see what happens. If after burn in I still am having the tweeter issue I will pull the xovers, unsolder the notch filter, and clean the pads up. I did that with one of the pads that would hardly take solder using a pencil eraser and then cleaning it with 90% alcohol. The solder on this pad would just pile up on top of the copper solder pad in a ball. Could be a potential problem.

It is really a subtle harshness but there. I did listen to some blues last night with high voice and cymbals crashing and did not notice it that bad. It is mainly under those conditions or when I am listening to a piano and it is the instrument up front. It is almost as if the tweeter is struggling to reproduce the sound.

I really don't feel that it is the RDO-198s that are the problem. They meter out just fine. My xovers were a mess with the electrolytics in the mids and maybe they were introducing noise into the circuit???? Who knows. Time will tell.

How do you like the Clarity Caps?

PreCd

I had an old tuner laying around from many years ago so I hooked that up to my preamp and the new capacitors are running 24/7. Should know more about how they are going to sound the middle/late next week at that rate.

audiocr381ve

PreCd wrote: »

When I placed the notch filter on the boards I did notice that the solder pads had oxidized. Being new to all this I did not understand at that time that this could be a problem. The acid in the flux is supposed to take care of some of the oxidation but I do not think it eat through all that was on the board. I am going to let it run for a while under the current setup and see what happens. If after burn in I still am having the tweeter issue I will pull the xovers, unsolder the notch filter, and clean the pads up. I did that with one of the pads that would hardly take solder using a pencil eraser and then cleaning it with 90% alcohol. The solder on this pad would just pile up on top of the copper solder pad in a ball. Could be a potential problem.

It is really a subtle harshness but there. I did listen to some blues last night with high voice and cymbals crashing and did not notice it that bad. It is mainly under those conditions or when I am listening to a piano and it is the instrument up front. It is almost as if the tweeter is struggling to reproduce the sound.

I really don't feel that it is the RDO-198s that are the problem. They meter out just fine. My xovers were a mess with the electrolytics in the mids and maybe they were introducing noise into the circuit???? Who knows. Time will tell.

How do you like the Clarity Caps?

I like the Clarity Caps a lot! I especially like the Mundorfs. Someone said that Mundorfs added very little to no color, and they were right. The Mills definitely colored the highs, but in a good way. The Mundorfs are verrrry sweet sounding coupled with the Clarity Cap PX's. I prefer this combo to the Sonicap/Mills combo for sure, although they're both nice.

Phasewolf

I hope I misread what you said acid core solder is not ever too be used on circuit boards. Please tell be it was normal flux and not acid based flux.

PreCd

Phasewolf wrote: »

I hope I misread what you said acid core solder is not ever too be used on circuit boards. Please tell be it was normal flux and not acid based flux.

I spoke out of ignorance there. I am using Cardas solder so probably not acid core flux. Now that you have said that I definitely need to go back in to the notch filter area, desolder, clean the pads up, and resolder.

Phasewolf

I just wanted too make sure acid core solder would not be a good thing for sure.

PreCd

Phasewolf wrote: »

I just wanted too make sure acid core solder would not be a good thing for sure.

I am glad you chimed in on that as I was about to assume that possibly the acid in the flux had eaten through the oxidation. Now that I know that Cardas does not have acid in it I will pull the xovers and work on that section.

Or I guess I could say you have gotten me into some work again!

PreCd

Ok. I have around 140 hours on the new capacitors at this time. I have been running either a tuner or CD player non-stop and should hit the 200 hour mark Thursday. I have been using my old CD player so tonight I will hook the good one up and give it a listen. Report back then.....

PreCd

Ok. Hooked the Marantz player up last night and did some critical listening. Things are really shaping up. The speakers are gaining definition and the tweeters seem to be getting a little better as far as the harshness goes. Jury still out on that one for me but the 2BTLs held my attention and I am starting to see the light at the end of the tunnel. RDO-198s are the only hurdle left to cross and hopefully they will continue to improve as the caps burn-in.

Let me say that the tweets are not harsh on all recordings and some instruments are worse than others. Steely Dan Aja is one of my go-to test recordings, the remastered version. Also Diana Krall Live in Paris. Some stuff on both of those recordings are showing the harshness I am speaking of just to let everyone know I am not using a 1975 Kiss Live recording as a reference!

PreCd

Well gang. I have found out that everything sounds so much better with the large inductors in both speakers connected to the xovers. 2nd mistake I have made doing my mods. O well. I have had the crossovers out about a dozen times so I guess I was due for lightning to strike. I heard a resonance coming from my right channel and decided to swap MW6503s out with each other. Then decided to meter everything out while I had the speakers open. Found nothing on the black/white of the right channel. Popped the radiator and found the 2 large inductor leads going to the crossovers hangin in the wind. Funny thing is they did not sound too bad like that! Another funny thing is that later the resonance was coming from a old CD player case that I had laying close to the radiator.

So now I am sure everything is connected and no damage is done. I wanted to let everyone know what I had done though. Not fair to not report the bad with the good.

I was not going to report back until tomorrow when I officially had 200 hours on the caps but I am going to for the sake of impatience. I am sure not having the large inductor in my right channel not hooked was affecting my sound however I can honestly say it was not too bad. Anyways after 195 hours the 2BTL mod sound pretty freaking good. Imaging has been greatly enhanced. Better detail in the music, i.e. coughing on live music, background voices talking under the music, and instruments I never heard before in music I am familiar with. How can that be bad.

My advice after all this would be to study on what you want to do. Don't be afraid to ask any question to those here. I even had a member get on a couple of phone calls with me to help, total stranger too. Upstanding citizen! Don't waste your time with electrolytics in the crossover. You may think that the speakers were engineered for electros but it made monetary sense for the maker and caps of this era were not available at that time. Word Jesse. I thought I would play around some and make them work. Forget it. Replace them with good film caps, be done with it, and enjoy your music. It may save you having to keep pulling your crossovers thereby saving a stupid error like leaving your inductor unplugged. If you do not feel comfortable doing your mod have someone here that has been around awhile do them. Not beginners like me or others who have done only a pair of speakers.

I have to say I am only 3 months into my audio journey. I have had my SDA2Bs since 1987 but they were connected to a sub-par receiver, using a sub-par CD player, in a sub-par listening environment, and now things have changed. I am really loving it and am starting to understand all the hub bub about everyone calling this a hobby. It is. And what a wonderful hobby it is.

More later.

Joe08867

Got to love those OH CRAP moments. I think everyone has had one at some point.

PreCd

Ok time to check in.

My speakers sound very musical. I love them. Over the past Christmas holiday I found the time to enjoy some time with my brother and we replaced the filter capacitors in my Adcom GFA-555. I forgot who said it but every thing matters. That statement is true. Every thing I do changes things for the better.

Anyways my speakers are musical, what more can I say. The whole system is beginning to sound beautiful. I do not know what else I can do to the system (I am sure there will be some suggestions) but I believe wall treatments are now in order.