Converting a Fisher X-10 to Bozak B-401 Rhapsody

Discussion in 'Speakers' started by sruddy, May 17, 2017.

  1. drbiggles

    drbiggles I like bacon Subscriber

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    I ran a pair of 302's beautifully with a 17 watt tube integrated. However, when pushed the 302's could suck it dry. About 25 to 40 watts of tubes would be more than anyone would want. With 40+ of tubes or solid state, you can push them with authority when necessary.

    As you can see, the 302's can be run on nearly anything. It's not so much about the watts as it is about the quality. Bozaks are very revealing speakers. You're going to hear failings in your recordings, be they digital or analog. Shortcomings in your cd player, turntable, whatever, are all going to become clear. Thankfully, with your available amplification, quality ain't an issue.

    Biggles
     
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  2. Treyphan

    Treyphan New Member

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    Hello!

    Ok so I've completed the 1st of my Crossovers with the Tobin Mods. While they wont win any beauty contests, they seem to work well. I suppose I should've posted before hooking them up. lol
    I was pretty sure that everything was good to go. I'd found some good schematics and the questions I had were answered here. So I plugged her up, and she sounds GREAT!! Definitely a BIG change from the stock crossover, no surprise there!

    Just wondering if @Retrovert or @drbiggles could take a look and double check my work? Id appreciate it.

    Im going to start the other one now. Not sure I'll have time tonight for the Flower Pot Mid Covers or not. I hope I do. Question, would some 1 in Egg Crate Acoustic Foam work for the Mid Covers? Rather than cotton batting. I have some foam left over from a previous project. So it would be nice if i could use it, and save me a trip. Ill use batting though if its going to be better.

    I am still waiting for the Bypass Caps to come, and I do plan to make some really nice 'custom' x-over boards, and perhaps mount the externally, also considering "liberating" the tweeter and making some sort of Cabinet for it on top. IDK, that still in the planning stages.

    I also am VERY happy I installed the L-Pads from the get go. The Red and Black wires are running to it. Really nice to have the ability to attenuate the highs. The 7.5 ohm resistors I got 'just incase', will go in the spare parts bin.

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  3. Retrovert

    Retrovert AK Subscriber Subscriber

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    If the sound is good, you've done it right.

    Using the wrong inductor tap on the woofer crosses too high (800 Hz), and the woofer and midrange would overlap at the low end of the midrange (400 Hz to 800 Hz). This over-emphasizes the frequency band and causes comb artifacts which may or may not be audible.

    Using the wrong inductor tap on the midrange causes the midrange to cross too low and this chops off the high end of the midrange band (1,250 Hz to 2,500 Hz) leaving a hole.

    Most definitely audible. It sounds really, really bad. Another thread details that effect and I explained all the math. I'll just paste it in here.

    At 8 Ω, the points are 400 Hz (full large inductor for woofer, N-102 & N-104 tap) and 2,500 Hz (half small inductor for midrange, N-101 tap).

    Given the crossover frequency for an inductor is calculated as:
    f = R / (2 x π x L)
    we can see that doubling L will halve the frequency, while halving L will double the frequency. So we want a small midrange value to move the midrange frequency higher and a large woofer value to move the woofer frequency lower.

    If the full-value is used for the midrange, it will cross at 1,250 Hz (well, actually 1,157 Hz). So that will remove the upper end of the midrange, aside from what the tweeters provide via a first-order rolloff.

    From what was originally described, it sounded like the woofer was doubling the midrange because the woofer was using the half tap instead of the full tap. That would also create comb artifacts as two drivers not within 1/4 wavelength were at the same frequency, but since the drivers are vertical that tends to not be as horrible sounding as horizontal drivers.

    If the woofer was running with half the inductor it would cross at 800 Hz, and if the midrange were running at full the lower end would be 400 Hz (controlled by the capacitor) and the upper end be 1,250. So we'd have woofer(0 to 800 Hz) and midrange (400 Hz to 1,250 Hz). This will sound terrible. So I think this had to be the problem. Even if the midrange were correctly wired for 2,500 Hz, the doubling from 400 Hz to 800 Hz would be a problem, more so than might be expected because of the first-order rolloff.

    Easy way to tell: hook up a signal generator and sweep the range, see where the sound comes out. A signal generator can be built using a 555 if you don't have one. You don't need a scope or frequency counter for this, as accuracy is not imporant. One is looking for overlaps or gaps in the response.

    Ix-nay on the oam-fay.

    I'd go with the cotton batting since we know it properly functions and doesn't degrade. The foam disintegrate over time and liberate fine dust which can get into the voice coil. Foam off-gasses a variety of VOCs, and since the cabinet and midrange cover are sealed that is going to end up deposited on the driver.

    Also, the foam tends to work less well as frequency drops, so while it might work fine on the middle to upper part of the midrange, I don't know how well it works in the lower (< 800 Hz) range.

    Moving the tweeter high greatly improves the sound. So does switching to a modern soft dome. Biggles can tell you all about that.

    I suggest using the soft dome and putting the original tweeters in the cabinet underneath the cotton batting with a note about where to find them.

    Yes, permits on to dial in the exact amount of treble which varies by the type of music, room, and person.

    Question: you restored the polarity for the midrange so it now matches the other drivers?
     
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  4. Treyphan

    Treyphan New Member

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    Yes, I did. I remembered reading about that, and did encounter it reading the Tobin schematic. Through me for a sec...til I remembered.
     
  5. Treyphan

    Treyphan New Member

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    Well, second x-over finished! I'm listening to the Tobinized Bozak 302a Century's RIGHT NOW!!! Resounding success! Definitely recommended, as if any more was needed. I'm thrilled, this mod just took these to these Speakers to the next level. I AM FLOORED!

    And this is still without the "Mid Cover", which is happening tmrw, need to eat and the fiancee is calling. She says "im done" for the night now. Tha'ts fine, so glad I decided to try these mods.

    Also noticed what looked like Aluminum wire to the drivers when I was under the hood, like was mentioned earlier. Thats ok, Im 100% gonna change it out for some nicer OFC stuff. Probably some nice binding posts as well.

    The cabs need minimal work, ,and the grilles(fabric/frame/logo) are perfect. So these should be good to go by the end of the weekend. They have without a doubt become my "Main" speakers as of now. Thats saying a lot, Ive got quite a few sets of really nice speakers around here. IMHO But none that are like this, DREAM COME TRUE!!

    I'm also a little happier with the way this crossover looks, I am going to re-do these and mount them externally as well as the tweeters(whether the stock or new higher end ones) on the top. The least intrusive way I can. I'm not going to destroy these beauties. I've got some ideas.

    Thanks again for the help!!

    Ill be around way more often, well, I always was, just didn't post before. lol

    Ill update with Full speaker before/after pics when Im done spiffin' em up!

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  6. Retrovert

    Retrovert AK Subscriber Subscriber

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    Yeah, funny how that works. Bozak Cult knows of what you speak.

    Biggles had a similar epiphany once his were configured. Most do. The new capacitors make those crossovers sing in a way the originals could not.

    The key is the aluminum-cone midrange. Those with the paper cones do not have the same experience. The paper-cone B-209 is not a bad driver; I'd say it is one of the better paper-cone midranges. But it can't hold a candle to the aluminum cone.

    The midrange cover is a more subtle effect, but the overall improvement is substantial. Clean, pure sound.

    By the time you're finished you will have speakers that rival those costing many thousands of dollars to acquire and people will ask you what are those Bozak things, because nobody outside of the audiophile forums knows that name.

    Hmmmm. I would be very surprised by that. I have only seen aluminum wiring in the crossover inductors, and those had ferrite cores, too. Your crossover are copper.

    I suspect you have copper with tinned ends and the gray solder looks like aluminum.

    Silver-plated PTFE is always a nice way to go for new wire and it doesn't cost that much more than ordinary cross-linked vinyl-jacketed copper.

    The reason for the silver plating is not, as audiophools mistakenly claim, because it is a superior conductor. It has no effect on the conduction for audio. The reason for the silver plating is that the copper would normally be tin plated, except that PTFE must be applied at a temperature above the melting point for tin. But that temperature is below the melting point for silver, hence the silver-plating. The solder actually better wicks into the wire strands with silver plating, increasing solder loading, which is undesirable because the stiff wire is more prone to fracture. Anyway, just sayin'.

    You may have just bought your last speaker.

    Ask Biggles how many speakers he used to own and what he did with them once he got his Bozak's dialed in.

    You're welcome.

    You required remarkably little assistance as you did all the heavy lifting yourself and just wanted to confirm your conclusions. That independent work is unusual and worthy of respect. Props for that.

    Bozak Cult leaves no speaker behind.
     
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  7. drbiggles

    drbiggles I like bacon Subscriber

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    Hey man,

    Retrovert laid it down, read and understand.

    You'd know fairly quickly if you didn't do the crossovers correctly. Imbalance that would cause you to think we were all nuts and Bozaks suck. The covers over the back of the midrange will make an audible difference, they will get even better. The midrange (where we live) will clean up and pop into a very clear view. Do not pass this step up.

    Once I got my first pair of Bozaks correctly updated, I had an epiphany. For the first time in 50 years, I realized that all the piles of speakers I had stored were all worthless to me. They paled in comparison. This put me on a 3 year track to sell everything but the Bozaks and my Stephens Trusonic 80FR project.

    Cheers!
     
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  8. Treyphan

    Treyphan New Member

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    Firstly, guess I havent figured out how to break up the Qouted Text to answer each point.

    Ill do it like this for now. Ill figure it out sooner or later.

    Regarding wire, funny....I have OFC AU plated teflon wire i planned to use, and totally agree with all your points, its also why i like it. Not because of some voodoo on the sound!! It sure does take solder easy!.


    Glad to hear its porbably tinned Copper, was a bit worried when I stripped a bit of the original wires, and saw dull grey, though im sure they wouldve tinned more than just the ends now that i think about it!! Still think ill update at some point.

    Thank You for the compliment. I try to be very meticulous in my work. It pays in the end....in multiple ways. Do it right the first time. If i dont know it, learn it well first. yadda yadda

    Regarding now seeing what the Bozak Cult knows....BINGO, still just as happy today. Infact i got u p 3 hours early to listen to them. That should say alot. Id compare it to a kid on xmas morning laying in bed waiting til its just early enough to bug Mom and Dad and drag them downstairs. lol So my coffee this morning was wonderful, sitting in my robe on the couch, listening to Stan Getz through the McIntosh to the Bozaks, was just...well......astounding, it transported me. I lost myself in the music, in a way few systems have allowed. I was completely submerged in the sound, I wont go into a bunch of audiphile(or phool may be the same thing lol) terminology to describe these. Its trite imo, and isn't needed for this review, my review. Or post.....that is quickly turning into such. Ill leave that to certain Audio Publications, that WAY over use words like that, to describe what is most of the time over priced equipment, spun with the whole 'Boutique' appeal. Not there isn't a lot of good stuff. I sure haven't heard and donit know it all.
    These Speakers just do it all right, yeah they.re vintage....so? Yeah, they have the tweeter over the Woofer.....so? Yeah, modern speakers will outdo them on the very top end....again....so??? Im an educated, intent listener. I'm over analytical, critical to a T, a perfectionist....you get it. IF youre in this thread you most likely are too.
    But I also remember why I got into this hobby/lifestyle.....THE MUSIC. I was fed up with sub par sound, so I decided to dedicate my life to re-creating, as closely as possible that sound that the 100s of live concerts and shows I've been to brings me. Its pure joy when a good guitar lick comes in, a crerscendo in classical music, when the horns are just killing it in Jazz.....the gorgeous twang on old country and bluegrass....THAT is why I do this!!! That's what I chase. Some say it an endless chase.....but to Retroverts point....I think the part of the chase for speakers is over...really. These are that good, the music fills my listening space in a way that makes me damn near cry, I'm sure it some point it will. Its emotionally involving like few I've heard.
    I may seem over exuberant....and god damn....thats cause I AM!

    These speakers allow you to listen to your music...not your system, as I like to say. They seem to somehow disappear completely, quite the feet considering the giant size. They sound perfect, look perfect, and well....are perfect. Thanks first and foremost, Rudy Bozak, for bringing us these wonderful Speakers, Thank you to the Late Pat Tobin, for all your work to make them what they could be....and lastly but most definitely not leastly, Thank You @Retrovert and @drbiggles for helping me implement it !! You've all played a part in bringing me the sound I've longed for my ENTIRE life! For once to not sit and nitpick..."well I wish it was better here...or there"....its well....AWESOME!

    And thats with more mods to come, albeit less of an impact, each bringin' even more sonic nirvana.....guess Im having a speaker sale soon!!


    Bozak Cult Leaved No Speaker Behind! I'm on board with that, all the way!!
     
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  9. Treyphan

    Treyphan New Member

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    Indeed!! Cheers to that. Ill update again after the mid covers are in. Oh, and I love and Agree with that PWK quote! ;)
     
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  10. Retrovert

    Retrovert AK Subscriber Subscriber

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    Just bracket each portion with the square-bracket Quote and then /Quote tags.

    You will need to cut-and-paste those tags, again always in brackets, into the regions you are separating so it looks like:
    Code:
    [Quote]Text You Are Quoting[/Quote]
    Your Response
    
    [Quote]Text You Are Quoting[/Quote]
    Your Response
    
    The tag will look something like:
    Code:
    [QUOTE="User-Name, post: Number, member: Number"]
    
     
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  11. Treyphan

    Treyphan New Member

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    Thanks for the tip on quoting @Retrovert!

    So I’m still just as astounded and thrilled with theses Bozak’s! Ear to ear grin! Had a buddy over last night, his jaw is still on my floor.
    Funny part is, he HAS a set of nice original 302a Century’s, however, he also has a wife who isn’t fond of his Audio Hobby.
    So they’re being stored/hid lmao at his Brothers home, where they are being run by an early 2000s RCA RECEIVER! Just waiting to fry a tweeter when pushed with those enemic “amps” in that thing.

    Had a question...the wire I used, to run from the x-over to the L-Pad, should I be concerned with length? Added capacitance, etc?
    I kept it as short as possible, allowing a few inches slack, for when the panels are removed.
    Wires are probably as long as the amplifier hookup wires from the crossover.

    Just curious, may not be enough to worry about.

    I’m also at a crossroads, on what to do about tweeters. I’m way happier than I thought with them in the original position. Still, the thought of ‘liberating’ them intrigues me. At that point with all the work, maybe newer better tweets are in store?!? Idk, lots of ways to go. Maybe the originals and a super tweeter to cover above 10k or so? Time will tell.

    Also Impatiently awaiting the arrival of the UPS Dude, who has my bypass caps!!
     

     

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  12. drbiggles

    drbiggles I like bacon Subscriber

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    Hey Treyphan,

    Don't sweat your l-pad wire lengths. If it was measured in feet, then yes. But your runs are on the very short side.

    There are many ways to play with the tweeters. I found that with the l-pad, in my smaller 12x14 living room, being able to attenuate them handled most of my issues. Mostly because I could finally HEAR them. You can add a coupla washers on the bottom mounting screws of the tweeters themselves and tilt them up a bit. You can also add an inductor to the B200Y tweeters and cut them off around 8 to 9k. Then add a super tweeter up on top to carry things up.

    I can say from experience that mounting them in a small cabinet sitting on top of the main cabinet is the best. But it can get expensive, and it's a fair amount of work. I picked up a pair of Frazier Midgets and rebuilt them to house a pair of SEAS T25 soft dome tweeters. I crossed these over at 2500hz, they go all the way up. I generally don't use Bozak tweeters in my setups, they're the only weak point of the system. This is only because they start to die and leave the game altogether at around 10 to 12k.

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    Biggles
     
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  13. Retrovert

    Retrovert AK Subscriber Subscriber

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    I have suggested either:
    (a) Changing to a modern tweeter, such as a soft-dome. With a tweeter capable of reproducing above 20k Hz, I suggest an inductor to limit the high end. See below. I also suggest keeping the Zobel to tame the impedance rise tweeters have starting at about 10k Hz.

    (b) Adding a supertweeter to pick up at about 10k Hz or so. The ribbon tweeters may be better than the pizeos. I've suggested, but so far this has not been used, one of the AMT clones. Parts Express sells Chinese clones now that the HEIL AMT is off-patent. I don't have any personal knowledge of them, but it seemed like a nice tweeter. I thought about adding these to my cabinet, but I have separate electrostatics. Again, a band-pass is needed, see below.​

    When adding a supertweeter, and with the B-200Y remaining:
    (1) Add an inductor to limit the B-200Y to 10k Hz, basically a band-pass the same way the midrange crossover works (capacitor for the floor, inductor for the ceiling). This is needed for two reasons. The B-200Y cannot go high and starts to distort. Also, the drivers will overlap and this can cause comb artifacts.

    (2) Add a band-pass filter for the supertweeter, using a capacitor to set the floor to 10k Hz and an inductor to limit the ceiling to 25k Hz. The reason for the limit on the supertweeter is that if your ampliifer ever has ultrasonic oscillation, and many do, it will burn out the supertweeter in no time.

    (3) Add an L-pad after the supertweeter's bandpass and across the driver to balance the driver to the other drivers lest it sound too bright.​

    If you have a scope I suggest looking for ultrasonic oscillation anyway, as adding some Zobels to the amplifier can tame ultrasonic oscillation which adds distortion and robs power. Even if it isn't present, adding the inductor to the supertweeter is a good idea. Don't worry about the phase shifts. Tweeters are so phase shifted anyway, that it's not going to matter.

    Speaking of phase shifting, I suggest you try to time-align the tweeter by positioning the cabinet at the acoustic center of the other drivers. This is what Dalquist did.
     
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  14. Treyphan

    Treyphan New Member

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    Great!! Thats what I thought, but appreciate you confirming it. I mean we arent dealing with Tonearm wire where a few PF may matter. But.....I dont know it all, so Im glad I asked.

    Again, great info! TBH, these are good to go in my room(about your size but a few feet deeper) the dials do wonders. However, As these will be my Main speakers, Im looking to go all the way. I see you are have some great woodwork skills! Those Midget cabs turned out great. I also like to think I know my way around woodworking. So that sounds like more fun!! I have some different ideas(aided by more ideas from You and Retrovert.)

    Question...the tweeters dont NEED a sealed box, correct? They are 'sealed' already within their 'case'.

    Im gonna go one of two ways, mount the original tweeters up top, with a super tweeter or:

    Just go for a Nice Soft Dome tweeter similar to what you have.

    You'll see in my next reply to Retrovert, what tweets I plan to add.


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    Biggles[/QUOTE]

    Again....gorgeous speakers! And great job on the woodwork!! Mechanical, Electrical and Wood....the Audio 'Hat Trick'!! Love when someone can do it all on their stuff. Im the same way, just dont trust other people(normally) to do my stuff. Not that there arent other WAY more qualified people, I just dont trust my luck to get them! lol
     
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  15. drbiggles

    drbiggles I like bacon Subscriber

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    Treyphan,

    I didn't say so earlier, so I will say so now. The B200y tweeters do what they do exceptionally well, very nice tweeters. It's just their ability to reach up above 12k that sucks. So, whether you choose to just add a super tweeter or go all new, you're not cutting any corners.

    Tweeters generally do not need a sealed cabinet. However, the tweeters I've used do want a baffle. I've tried the ones I've tried without a baffle and they sounded really nice, for the most part. But when I took the same tweeter and put it in a box with a front baffle, the pinpoint accuracy, focus improved. That's why I ended up putting these in a small box. Ultimately, what you'd want to do is build small tweeter cabinets using the same design as your 302's. This would blend them in and make it seems as though they're original to the system.

    Biggles
     
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  16. Retrovert

    Retrovert AK Subscriber Subscriber

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    For best reproduction of sound a tweeter requires a baffle. A small cabinet with a long face, such that the tweeter may be off-centered mounted (see below, is therefore best.

    Lack a baffle the tweeter's front-wave moves around behind it in a spherical pattern, and the driver operates in what is called 4Pi space. With a baffle the output's rearward movement is prevented, and the driver operates in 2Pi space. Removing the rearward dispersion has the profound effect that 2Pi space is 6 dB louder than 4Pi space. Search for "baffle step" for further reading. The rearward is part of why open baffles require a very large baffle surface to ensure that the front-wave cannot leak around the baffle to the rear where it is lost, reducing output. (The large baffle also prevents the back-wave from interfering with the front-wave.) For brevity, I'm eliding the discussion of dipole radiators which emit from front and back; electrostatics are an example of this. One can go mad pondering all of this.

    The distance between the tweeter and the baffle edges determines the frequency at which the shift from 4Pi to 2 Pi occurs. In consequence, placing the tweeter off-center, such that the distance to the edge on one side is shorter than the half-wavelength of the lowest frequency being reproduced and longer than multiples of that waveform, delivers the best results. Remember, the sound close to the edge wraps around the cabinet, but the sound along the long face does not, so that will be emphasized and dispersed into the room. At the same time, the wavelengths may be unequally amplified by the baffle. Speakers often end up being a compromise of factors, many of them regarding aesthetic placement of drivers lined up in a row for marketing reasons. The speaker gods giveth, and the speaker gods taketh away.

    While the exact dimensions of the baffle are likely less critical, what really matters is that the tweeter has a baffle of some sort. This baffle need not be complex or expensive; a baffle may easily be fabricated out of foamcore board, with some angle pieces on the end to hold it upright, to experiment with size and placement. Remember, the tweeter is sealed so the backwave has already been removed from the equation. All that matters is how the sound disperses along the baffle.

    To avoid reflections the baffle must either (a) be chamfered or (b) permit flush-mounting of the tweeter. Felt has been used to dampen sirface reflections. One can spend one's entire life down the speaker rathole. In such case, great is the enemy of good enough.

    Discussions about baffle transitions from 4Pi space to 2Pi space are equivalent to having different prophets dispersing the Holy Word of Acoustics: every speaker designer or owner has a prophet; each prophet preaches a message of varying difference from the others; prophets are usually intolerant of another's beliefs; and followers of one prophet will cheerfully slaughter the followers of other prophets for perceived deviations from dogma or Holy Writ, no matter how minor.

    Bozak Cult follows no prophet and instead follows whatever makes the most sense, which usually turns out to be J.R. "Bob" Dobbs.
     
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  17. Retrovert

    Retrovert AK Subscriber Subscriber

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    Right. The output also gets kind of spikey above about 10k Hz. This was a problem of all of its tweeter contemporaries. The Electro-Voice T35 has the same type of issue.
     
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  18. Treyphan

    Treyphan New Member

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    Thanks for the super detailed response retrovert! Helps a lot! I get the ‘rathole’ comment too. At some point the law of finishing returns comes into play.

    I certainly keep the info in mind as I construct my tweeter cabinet/baffle/mount. Whichever way I go. I’m close to decided. I think

    One thing I now know for certain is the “Mid Cover Mod, using a plastic flower pot and 1 inch cotton batting is WORTH IT!

    I got the covers made and installed last night. While not as big an improvement as the x-over Mods. Which I wasn’t expecting, tbh I wasn’t expecting a ton, maybe moderate but audible improvement.

    It was well beyond moderate, audibly improved the entire mid section, and seems like the mid and woofer blend even smoother now, between the lower xover point of 400hz and the cover that cancels those nasty mid resonances.

    Cleared everything right up. Really noticeable in my system, which is very revealing. The sound is intoxicating. Not sure how the mids could even get better, but they did.

    These speakers continue to amaze me each time I listen. This may be the most substantial audio mod I’ve ever done. To unlock this speakers potential in this way, well it makes me a very happy Man!
     
  19. Treyphan

    Treyphan New Member

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    ****quick update****

    Listening to ‘Reckoning’, a GREAT live acoustic album by the Grateful Dead, around 81.

    It’s well recorded, and these speakers are recreating Brent’s piano in a superb way, a test I like to use. Piano seems to be one of the harder instruments for speakers to really nail.
    I believe I’ve read the actual reason for that, though can’t rememeber right now.

    Anyway, everything I throw at these comes flowing out in such musical fashion it’s scary. In a good way. lol

    These were designed in the 50s! That’s nearly 70 years ago! Rudy Bozak was a freaking genius! I know I’m late to the party, just glad I made it at all!
     
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  20. Treyphan

    Treyphan New Member

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    Location:
    Lake Orion Mi
    Well, I’ve just been so busy I haven’t had time to get to the Cabinet restoration. “Hopefully” get started this weekend. As I mentioned, they are in great shape, too nice for a Re-veneer, as much as I would love to make em look brand new with some real nice veneer, the original will re-finish quite nicely. Why destroy a peice if history?
    I’m still enjoying these speakers more than I ever would have thought possible. I figured I’d post some Bozak Porn while I’m staring at them drinking my coffee.
    The pic shows them without the grilles, I’ve got em, and they’re mint. Just listen without em.
    Also, I’m not done with my audio rack yet, its out in the garage drying, so excuse my setup. Kinda funny to see McIntosh Tube stuff on a mish mash of cheap end tables. Lol Doesn’t effect the sound though! ;)
    Each speaker is being run by an MC240 that’s strapped, Incase people were wondering if I was bi-amping. It sounds amazing.

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    Last edited: Jul 12, 2018

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