Restoring Bozak E-300 cabinets

[sol7]

You could use a sacrificial blade on a table saw and cut the trim off. There are probable small trim nails hold on the trim, along with the glue. At least on mine there are. You don't want to ruin a good blade cutting though the nails.

 

[sol7]

I take that back, I don't think mine are nailed, just glued.

 

[vinyldavid]

Biggles is very passionate about his Bozaks.

I wouldn't go so far as to say garbage, but I would say not nearly as good and you can do better. I might even say inferior. But if I were on a desert island with a pair of B-302s with paper cone tweeters I could live with it.

The B-200Y uses the same design as the B-209B midrange. It is a very nice tweeter. Paper cone tweeters are generally not much good beyond 10K, and the B-200Y will go beyond that.

The B-200X is proportional to the other drivers while the B-200Y is much louder, so if you go down that path, you will need to add the Zobel in the Tobin modification to re-establish the balance.

David is also very passionate about his Bozaks, and along with saltwater, we moderate and run the ever-growing Facebook Group "Bozak Speakers".

The B-200x is anemic out past 6khz, and all the examples I've heard have had a terrible high frequency resonance when fed modern material through them-as if the excess HF energy has nowhere to go. I can hear the Y's in my B-302A's up to 17-18khz, but the level is VERY reduced.

Like Biggles, I have an extremely violent negative opinion of the B200X, especially in single pairs. With the hemidome in my lowboy Concert Grand, it's not AS bad, but I still don't want to listen to them. My hemidome is getting B200Yc's, and the pair of 16ohm B-209Bc's and my 4 B199Ac's are going in the midrange and woofer positions.

 

[Retrovert]

The B-200x is anemic out past 6khz, and all the examples I've heard have had a terrible high frequency resonance when fed modern material through them-as if the excess HF energy has nowhere to go. I can hear the Y's in my B-302A's up to 17-18khz, but the level is VERY reduced.

Hey, no argument with you about the limited response. I didn't say they were good tweeters. I just said I wouldn't say they were not complete garbage. A significant difference exists in that comparison. Here's what I wrote:

I wouldn't go so far as to say garbage, but I would say not nearly as good and you can do better. I might even say inferior. But if I were on a desert island with a pair of B-302s with paper cone tweeters I could live with it.

The B-200Y uses the same design as the B-209B midrange. It is a very nice tweeter. Paper cone tweeters are generally not much good beyond 10K, and the B-200Y will go beyond that.

I think "inferior" is very much in line with your opinion. Did I not say "not nearly as good", "you can do better", "inferior", "not much good beyond 10K"? Rudy Bozak made a good paper-cone tweeter for the 1950s that was nowhere near as good as its replacement.

Look, I could have said, "Even the B-200Y is terrible when compared to a pair of JansZen 65 or 130 electrostatics". Even compared to a Radio Shack Electrostat 3." But that's not what we're talking about. So I think my assessment is fair and accurate.

My B-313's have the Y's, my B-305 center/omni will have Y's installed (along with a pair of B-209Bc's) when I rebuild it, as will my B-502's. Like you and Biggles, I prefer the B-200Y. I think everyone does after hearing the X vs. Y.

Biggles and I have had innumerable discussions about Bozaks, including the benefits of replacing the B-200X with the B-200Y and moving the tweeters because neither of us listens a foot off the ground and we don't have ears in our knees. I've suggested many people replace the X with the Y and use the Tobin Zobel to match the levels.

 

[Retrovert]

One more thing. I wouldn't have spent a bucketload of cash on B-200Y tweeters (eight of them to replace all of my X tweeters) if I didn't think this was an improvement clearly worth making.

I'm just not willing to say "complete garbage". The B-200X is a tweeter with limitations. Many people can't hear the difference or can hear it to some extent but don't care.

I understand that discussions about speakers can become very passionate, just like discussions about phase splitters, bias techniques, and GNFB, which often veer into holy wars where everyone dies, the earth is salted, and sad videos of baby penguins killed because people used the wrong tube topology are uploaded to YouTube.

I was trying to correct the characterization of "garbage" to "inferior and limited". My review of the B-200X is that it is limited and inferior to the B-200Y, which I think is a fair assessment.

Just FYI, as I realized this might be the issue, this was not an attack on Biggles. It was more a spilling over of our (Biggles and my) ongoing offline discussions. Ask Biggles about our extensive Bozak discussions, on the forums, via PM, and via telephone. I think he would agree that he and I are in total agreement when it comes to making our Bozaks sound as awesome as we can and that we are total Bozak fanboys spreading the holy word of Rudy.

 

[vinyldavid]

Hey, no argument with you about the limited response. I didn't say they were good tweeters. I just said I wouldn't say they were not complete garbage. A significant difference exists in that comparison. Here's what I wrote:

I think "inferior" is very much in line with your opinion. Did I not say "not nearly as good", "you can do better", "inferior", "not much good beyond 10K"? Rudy Bozak made a good paper-cone tweeter for the 1950s that was nowhere near as good as its replacement.

Look, I could have said, "Even the B-200Y is terrible when compared to a pair of JansZen 65 or 130 electrostatics". Even compared to a Radio Shack Electrostat 3." But that's not what we're talking about. So I think my assessment is fair and accurate.

I AM saying they are complete garbage. That's the key difference. And there's a huge difference between 6k and 10k. I do absolutely love Rudy Bozak's designs, his engineering skills, and his passion for recreating orchestral music. But, I think that he did learn something very important between 1950 and 1960, and using the B200X when Y's are cheap and easily available is, in my opinion, just sad.

I have yet to hear the JantZen electrostatics, but I would love to! My friend with highly modified Concert Grands is going to be adding in RAAL 40-150D ribbon tweeters over the B-200Z's at about 10k. Since he's using one tweeter per box (he's in a glass room, it works well), it will help with overall extension. We already tried replacing the Zc with the RAAL, and the results were breathtaking, but not quite as real sounding as the Bozak driver.

My hatred of the B-200X is strong enough that I sent Biggles a quad of X tweeters to play with, since he'd never played with any. Now, I'm mostly converting my coaxial speakers to the Yc tweeters for less obstruction, and to try and get my friend with 1956 upright CG's a set of 16 Y Alnico tweeters to upgrade his with.

 

[drbiggles]

Ha! I still have VDavid's X tweeters in the garage, all tucked away. I know what they are, and their limitations. Some day soon I hope I will have an excuse to pull them out and put them to some use.

I have a 1954 deMars corner speaker and it's loaded with Bozak guts. 4 of which being the B200X tweeters. The beast sounds okay with Edith Piaf and other related treats. But she simply cannot do much more.

Biggles

 

[moondogtn]

Thanks for all the insight about Bozaks. I really enjoy reading up on it. I plan to finish buttoning up the one I did last weekend and start the other today, time permitting since I am on call.
You guys should post a link for the Bozak Facebook group.

Bill

 

[drbiggles]

The Bozak group is easy to find, just search for it and it's a closed group. It pops right up!

 

[mrphilco]

For anyone interested:

Before:

After:

I've finished the restoration and they are in my home office now.

The tops, bottom trim, and risers are new. The grille cloth is new. The speakers, N-10102 crossovers, and the basic cabinet shells are the originals.

I think the B-200X tweeters sound fine if possibly a bit harsh, but I'm satisfied.

Those of you inclined to do so may argue about the merits of B-200Y or B-200Z tweeters over B-200X, but I won't be participating in that activity. I'm happy with my E-300/B-302s, and that is all that matters.

 

[mrphilco]

P.S. These still have the original backs. I filled the extra holes. Not pretty, but who looks at cabinet backs?

 

[moondogtn]

Wow! Those look awesome! Great job. I'm still working on mine...getting closer....slowly.
Bill

 

[Sandstrom]

Hi Ron! Wanted to check into your thread. I was the AK member who sold Ron these speakers several years ago and am so pleased to see the lovely restoration that has been performed! I met He and his lovely wife at the Parts Express Audio Fest one time to deliver them. He was kind enough to send me a PM cluing me into his completion of the speakers (I somehow missed this thread). All I can say is wow! I love to see classics brought back and lovingly restored, so rewarding.

I had (and have) another pair hence why I let these go. The newer pair had to be cobbled together as the cabinets only came with X-overs and mids. With the help of two different AK members I was able to get complete woofer/tweeter setups to complete the set. I have been trying to sell this pair to no avail, so Ron if you want you can try out the aluminum Y tweets if you are so inclined, If we are ever in a position to meet up I can pull them for you as the speakers are just sitting here doing no one any good right now.

I do admit fully to the Ys having more extension but was not as dissatisfied with X's as I suspected I would be.

Bravo mrphilco!

 

[GD70]

Great thread and project!
I'm like you, liking to keep things as original as possible. The tweeter and cross over mod are the one thing I would probably do, especially because it was a factory mod.
The wood aspect is frustrating and you'll get it worked out, cool you have a friend that will make you new ones. If I was trying to remove those strips, I would have cut them with an xacto and steel straight edger running the blade along the joint seam countless times until it separated. Anyway, I've made my share of mistakes along the way on projects too! How else will we learn?
Keep going, you'll be proud to show them off and play for your guests.
Glenn

 

[mrphilco]

To Bill (moondogtn), Sandstrom, and GD70 - Thanks!

Glenn (GD70) - while this project is complete, I do still have the original tops with broken trim pieces. I may yet try to remove the remaining trim using the suggestion you have made. And then, who knows, I'll have to see if I'm crazy enough to add new trim to the original tops, refinish them, and reinstall on the cabinets. But I really doubt that I will do that as this job took up most of my summer, and I'm not inclined to do any more work to them if I do not have to.

Sandstrom - regarding the B-200Ys, that is very kind of you and I will send you a PM on this subject later. Thanks so much!

I wish to sincerely thank Sandstrom for selling the speakers to me in the first place; Philco Phorum member GarySP for building the risers and cutting new tops; and auction seller Joerent123 for kindly taking multiple measurements and passing them along to me so that the risers could be accurately reproduced and properly installed. Without their help, this project would not have been possible.

 

[GD70]

For anyone interested:

Before:

After:

I've finished the restoration and they are in my home office now.

The tops, bottom trim, and risers are new. The grille cloth is new. The speakers, N-10102 crossovers, and the basic cabinet shells are the originals.

I think the B-200X tweeters sound fine if possibly a bit harsh, but I'm satisfied.

Those of you inclined to do so may argue about the merits of B-200Y or B-200Z tweeters over B-200X, but I won't be participating in that activity. I'm happy with my E-300/B-302s, and that is all that matters.

STUNNING! You must be thrilled with the outcome!
I love to see a pic of the final setup I your office.
Job well done, the way it should be done!
Cheers, Glenn

 

[drbiggles]

Breathtaking and a huge congratulations for seeing the project through! And another congratulations to the team behind you making things happen.

Biggles

 

[mrphilco]

Thank you, Glenn and Biggles.

My opinion of the B-200X tweeters, now that the completed speakers are hooked up in my home office (photos later this weekend):

I don't understand why folks say that these tweeters are lacking in high frequency range. I've been listening to these speakers for nearly an hour, and to my ears, they have plenty of range. And I can still hear up to around 17 kHz. I actually had to turn the treble down on the Pioneer SX-1500TD I am running with these Bozaks.

Listening to strings (Mid Century beautiful/mood music - the type of music that was in vogue when these speakers were new), these Bozak B-302A speakers are probably the most life-like, the most realistic (pun not intended) speakers I have ever owned - in my opinion. And vocals - Nat King Cole, THE best of his time - it's just like being in the recording studio with The King.

The only complaint I have is on passages by Jackie Gleason's orchestra, Bobby Hackett's cornet is too shrill over the B-200X tweeters...very slightly distorted. I do not detect any distortion on strings, just Hackett's cornet (very slight, and not on every selection).

As you can see, I don't listen to much rock'n'roll anymore.

Now, based upon these thoughts, if you want to tell me that the B-200Y is worth pulling these damn things back apart because they will eliminate the harshness and (very very slight) distortion in Hackett's cornet, I'm all ears.

 

[rayj]

Hello, please allow me to chime in if I may. I just bought a pair of B201 Sonoras in the birthplace of Bozak, Norwalk CT. I think that maybe they came from an employee of the Bozak company's estate, and for the record, yes it was Goodwill $25. The veneer all around is in excellent shape and I was not at all trepedacious of hooking them up and listening. I was as pleased as I could be having had 2 different pairs of epi's on that same B position . I have Celestions as A speakers. They please me the same as the epi's and I venture to say I'll value them even more, as they are a hometown original, and I will check out the tweeters to see what I have.

 

[Sandstrom]

Thank you, Glenn and Biggles.

My opinion of the B-200X tweeters, now that the completed speakers are hooked up in my home office (photos later this weekend):

I don't understand why folks say that these tweeters are lacking in high frequency range. I've been listening to these speakers for nearly an hour, and to my ears, they have plenty of range. And I can still hear up to around 17 kHz. I actually had to turn the treble down on the Pioneer SX-1500TD I am running with these Bozaks.

Listening to strings (Mid Century beautiful/mood music - the type of music that was in vogue when these speakers were new), these Bozak B-302A speakers are probably the most life-like, the most realistic (pun not intended) speakers I have ever owned - in my opinion. And vocals - Nat King Cole, THE best of his time - it's just like being in the recording studio with The King.

The only complaint I have is on passages by Jackie Gleason's orchestra, Bobby Hackett's cornet is too shrill over the B-200X tweeters...very slightly distorted. I do not detect any distortion on strings, just Hackett's cornet (very slight, and not on every selection).

As you can see, I don't listen to much rock'n'roll anymore.

Now, based upon these thoughts, if you want to tell me that the B-200Y is worth pulling these damn things back apart because they will eliminate the harshness and (very very slight) distortion in Hackett's cornet, I'm all ears.

I kind of understand where you are coming from, when I had the speakers I enjoyed the highs more than all of my reading and research told me I thought I would (very natural). Now, when I tried the Y's in my second pair I will not deny that I was getting more top end sparkle. I did try making my own Tobin crossovers but was lest satisfied as I felt that it attenuated the highs too much. To be fair, I do believe I may have had a wrong value resistor in the circuit, so it probably wasn't a fair assessment. That being said, for me the addition of the Y's sounded fine to me with the stock crossover, basically as before with more high frequency headroom if that makes sense.

Not sure if the harshness you are hearing in the Hackett piece would be tamed, I would have thought the X's would be smoother in this regard. Perhaps this is what the correct crossover tweaking helps as much as anything.

Anyway, I am really pleased that you are happy with them, I get so much satisfaction when these kinds of worthy components get their proper care and feeding.

Brian