cowboy99 Posted November 4, 2015 Report Share Posted November 4, 2015 Recently scored a nice pair of T1030's. Nice shape and recently professionally 're-foamed. Was asking $170.....I gave him $200 feeling almost guilty.Two weeks later by dumb luck I inherited another pair of BA, a beautiful set of T1000's that had been stored/unused for 20+ years with original surrounds in excellent shape.......Unbelievable !Have looked at the T1030 crossovers to consider which electrolytic caps to replace and I understand the difference in them and the T1000.Does anyone have the manuals or copies for these two models?Anyone one with schematics of the crossovers or freq specs?I was somewhat surprised to see that the 6" & 8" were different units from model to model, I'd read several times that they both used the same speakers??I've been in the process of building a multichannel BuffaloIII DAC with Aleph J amps for the primary 4 channels. So these towers are a real blessing towards that goal.A question for Gerry S. (if he would honor me) Any recommendations on recapping or replacing the HF cap with a more modern type or maybe modifying the T1000 x-overs to be more inline with the improved T1030 version for simultaneous use? Or would they interfere with each other as is?Don't believe replacing any of the mid & low freq cutoff caps with non-electrolytic would be a good idea, but unsure.I guess I could reverse-engineer a schematic and attempt to calculate the designed freq cutoffs......But it certainly would be nice to have factory data.As for the queries comparing the actual 'sound' differences between these models...after recapping I'll get a better opinion. They both sound really nice as is, but different. Quote Link to comment Share on other sites More sharing options...
Gerry S Posted November 6, 2015 Report Share Posted November 6, 2015 Please refer to: Boston T1000 vs T1030 Started by morkys, Mar 16 2009 10:01 AM The driver alignment difference alone would make replicating the T1030 "sound" on the T1000 difficult (if not impossible) in the "near field".The T1000 and T1030 use identical drivers and enclosure volumes, but the crossovers are NOT interchangeable.That's because the two systems have different physical driver alignments, requiring a different approach to crossover design.As far as specifics, the T1000 crossover uses three "parallel" networks (one each for the woofer, midrange and tweeter section).The T1030 uses a "quasi-second series" network between the woofer and midrange sections, a parallel network on the tweeter. The crossover frequencies and slopes are also different, resulting in different "near" and "far-field" responses.As far as replacing caps, I don't think it's necessary. It could actually be detrimental to system performance and reliability (because of changes to the crossover frequencies).I would not operate both systems in the same room because of likely acoustical interference between the two. Also, each system has an impedance of 4 ohms at low frequencies; operating both systems at once (from the same amp) would tax the amp. Quote Link to comment Share on other sites More sharing options...
cowboy99 Posted November 20, 2015 Author Report Share Posted November 20, 2015 Thanks Gerry for the detailed response. I was afraid the. Two pair may not match up in a multichannel setup. One of each of larger electrolytic 120mfd caps in both the T1030s show signs of overheating (the leads overlapping body of cap have melted the plastic sheath/label)Still. It sure would be nice to have some documentation for these. Especially Thiel/Small parameters for the drivers in case I have replace them. Quote Link to comment Share on other sites More sharing options...
cowboy99 Posted January 12, 2016 Author Report Share Posted January 12, 2016 (edited) Well, after a few months listening, I'm much more impressed with the T1030s than my initial opinions.They amaze me with their separation and the sound stage. Continually hearing definitions that I've never heard from my all time favorite releases. Their really quite nice with all the digital audio I've acquired such as: HQ DVD-A, killer Steven Wilson remixes and various 24bit 96kHz Flac pro rips of vinyl masters & orig pressings (pbthal,DocRob & aksman, etc).Either my 50+yr hearing is getting much better (doubtful) or the crossover design/topology unlike any I've heard before. Comparisons are to some of better XO's I have used for years: EV X8/X36 even JBL N1200. And that's unmodded with orginial electrolytics . Although,hifreq side isn't near my hiend JBL N7000 w/pair of 077 prisms. The mid-low side is impressive. (Gerry, I took your advice & left as is). Quote:"The T1030 uses a "quasi-second series" network between the woofer and midrange sections, a parallel network on the tweeter. The crossover frequencies and slopes are also different, resulting in different "near" and "far-field" responses."Quasi-2nd series..... Unfamiliar with this type my interest is keen, and I plan to rev-eng circuit/schematic to understand the math/physics of your X0 design, if that's OK Gerry. I like what I'm hearing.....intend it as a compliment to your achievement. FWIW... Agree the T1000 can't be even compared to the audiophile T1030s Edited January 12, 2016 by cowboy99 Quote Link to comment Share on other sites More sharing options...
milosz Posted September 21, 2017 Report Share Posted September 21, 2017 HELP!!I have a Boston Acoustics T1000 crossover but I do not know how to wire it to the drivers or to the input from the driving amplifier. (I also have all the drivers)This late 1980's 3-way speaker system has two 8 inch woofers, a 6.5 inch mid and 1 inch dome tweeter. Obviously they all have to be wired to the crossover and the whole business needs to have a + and a - terminal for connection to a driving amplifier. I wrote Boston Acoustics and they could offer no guidance.Can someone help me figure out how to wire this up?I've drawn the schematic and taken a photo of the crossover. Some wires were still connected to the crossover - these wires lead to drivers and to the speaker systems's pair of input terminals, one + and one -. I've indicated these connection points on the schematic, and the labeled points' letter correspond  between schematic and photo. Quote Link to comment Share on other sites More sharing options...
cowboy99 Posted September 25, 2017 Author Report Share Posted September 25, 2017 Pretty sure I can help you. 1) I took full set of pictures of my partially disassembled T1000 without diconnecting any wiring for the main purpose of re-capping the x-overs. 2) Hand drew a schematic of the entire wiring hookup. Give me the day to gather it all. Charles Quote Link to comment Share on other sites More sharing options...
Pete B Posted September 28, 2017 Report Share Posted September 28, 2017 mike66 posted this on AK in response to your question: https://www.audiokarma.org/forums/index.php?threads/help-need-help-with-this-crossover-schematic.789008/#post-10942643 A 3 red wires, two woofer +, one to speaker in + terminal B 2 black wires woofer -, brown/white to midrange - C yellow to tweeter -, black to - input terminal D white wire to midrange + E brown to tweeter + I think that covers it. Good luck!  And gave these values:  Ferrite inductor is 2.75mH, yellow inductor is 0.42, and the red is 0.51.  Quote Link to comment Share on other sites More sharing options...
Pete B Posted September 28, 2017 Report Share Posted September 28, 2017 Edit: The 2uF cap C3 in my schematic below looks too small, it is in the bottom left corner and is large, is that actually 42 uF? Anyone? I posted this: I never heard these but always wanted to after reading the excellent reviewof them in Audio. I redrew the schematic in SPICE.The woofer to mid crossover is a series type that employs a fairly low parts countand is first order. I first saw it used in the DQ-10, it is also used in some AR speakers suchas the AR-48s as I documented here: http://baselaudiolab.com/AR48s.htmlStarting with the woofers it can be seen that the positive inputs are wired directly to themain system input. Low frequency signals including DC pass through the 2.75 mH inductorL2 and 80 uF C2 acts to shunt highs away from the woofer rolling it off and providing a path forhighs to the midrange. R3 and C3 appear to be roughly a Zobel for the woofer.R5 provides attenuation for the midrange and L3 is a low pass to the mid rolling off thehigh end to it. 16 uF C4 makes the low pass XO to the mid 2nd order. R4 and C5 providea Zoble for the midrange. C1 and L1 form a 2nd order highpass to the tweeter with thetotal attenuation to the tweeter controlled by the total resistance of R1 plus R2 and theratio controlling the Q or shape the that rolloff. Quote Link to comment Share on other sites More sharing options...
Pete B Posted September 28, 2017 Report Share Posted September 28, 2017 Very curious to see the T1030 schematic if anyone has it. Quote Link to comment Share on other sites More sharing options...
milosz Posted September 28, 2017 Report Share Posted September 28, 2017 This is excellent, thanks. This is much farther than I went into this. Very complete. Actually, I removed the drivers from the cabinet in 2005 when I noticed that the woofer surrounds were shot, and have used the cabinets for experiments since then. If you are interested in the experiments, you can see http://www.diyaudio.com/forums/multi-way/256074-road-3-active-speaker.html ) And then recently I cleaned out some storage space and came across the drivers and crossovers. I hated to just toss them away, so I refoamed the woofers and sold the whole lot on eBay at auction. This didn't result in very much income- about enough to ship them and then have a couple of coffees and a bagel- but now the drivers and xover will get a new life in someone else's hands and they will have the pleasure of tinkering, building and listening. The buyer needed more information about connecting the drivers than I had, and I noticed others over the years looking for crossover info on the T1000, so I started a few threads here and there thread and now we have all the answers.   HAHAHA the only thing I personally was able to figure out from this crossover is that one side of the tweeter probably connected to the brown wire at "E" -  but now greater minds have considered the matter and the answers are known!  Just a great job here.  A few last notes - each 8 inch woofer is mounted in it's own sealed enclosure, 1 cu ft in volume and with some poly stuffing in it- not tightly stuffed or packed, but not a "sparse" amount of fiberfill either. Moderate stuffing. The 6.5 inch mid has perhaps a 0.15~0.25 cu ft of sealed volume behind it. Also, this crossover is designed for the original T1000 system with woofers on the bottom of the cabinet's face, the midrange in the middle, and the tweeter at the top. Some subsequent T1000 version had the tweeter in the middle with the mid up top, that would have a different crossover design. Quote Link to comment Share on other sites More sharing options...
cowboy99 Posted October 1, 2017 Author Report Share Posted October 1, 2017 I agree, great job Pete. Don't have either of the official schematics. All I have is the 'chicken scratch' ones I've created myself. What you've posted matches what I drew up on the T1000. As far as the T1030 I feel it best to run any schematic that might be posted on it by Gerry S. and of course ask his blessing to post it first. That x-over is his baby! Quote Link to comment Share on other sites More sharing options...
Pete B Posted March 20, 2018 Report Share Posted March 20, 2018 I updated the schematic with corrections. Quote Link to comment Share on other sites More sharing options...
cowboy99 Posted March 20, 2018 Author Report Share Posted March 20, 2018 Thanks Pete, Got to appreciate a man finishining what he started. I've got an extra T1030 XO that is just waiting for me to pick it up one day soon. If you have any interest in documenting it. I'm not sure I.ll ever get around to it, plus your work would outclass any thing I would draw up. Charles Quote Link to comment Share on other sites More sharing options...
milosz Posted March 21, 2018 Report Share Posted March 21, 2018 Again many thanks to Pete B for his expertise and time. Now, this schematic is available to anyone who needs it - worldwide! If I come across a T1000 thread on Audio Karma, DIY Audio etc I will link to this thread here.  The T1000 and T1030 were / are decent speakers. Lots of them were sold. I imagine a good many are still out there, and I can imagine a number of scenarios where someone ends up with just the drivers, or just the drivers and a disconnected xover, and this schematic can help them sort things out. FYI, the re-foam kits available on Ebay, Parts Express, etc, are actually easier to use than you'd think on the T1000's 8 inch woofers and the midrange driver, worth it especially if you find a kit that's not too expensive. I bought a kit for $19 with 4 woofer and 2 midrange surrounds, plus glue, it worked just fine. Quote Link to comment Share on other sites More sharing options...
Pete B Posted March 22, 2018 Report Share Posted March 22, 2018 On 3/20/2018 at 5:37 PM, cowboy99 said: Thanks Pete, Got to appreciate a man finishining what he started. I've got an extra T1030 XO that is just waiting for me to pick it up one day soon. If you have any interest in documenting it. I'm not sure I.ll ever get around to it, plus your work would outclass any thing I would draw up. Charles Thanks Charles, but if you can believe it I just bought a pair of T1030 XO's on ebay a few hours ago, wish I'd seen your offer. I notice that the T830, T930 have series II and III versions were these aligned with the T1030 logically or T1000? Next question of course is if there were series II and III of the T1030?  Picture of T1030 AC001494 from ebay advertisement, I traced it out from the pictures but need the XO to measure the inductors: Quote Link to comment Share on other sites More sharing options...
cowboy99 Posted March 23, 2018 Author Report Share Posted March 23, 2018 Dam nit Pete, That was YOU I was bidding against. I was going to grab them to update my T1000's as an experiment. But the seller wouldn't do a break on shipping both of them .... which made me hesitate too long. Glad they went to the right home though cuz now we.ll all get a schematic for the T1030. Plus I've got bigger projects needing focus. See links, thats a cherry pair of JBLÂ L65A and a serious 200W x2 amp to drive em ....Heathkit AA-1800 ..the old Leach Super Amp Did you notice the caps are different between the two? https://drive.google.com/file/d/1-z5urNCCOy-4rRymUYgoLFWaMeD9CtrV/view?usp=drivesdk https://drive.google.com/file/d/1senj9hU4OTcmytK3YRBGEa_4AsQhkCJd/view?usp=drivesdk 30lb trans https://drive.google.com/file/d/1eOldw4f__yCVQsqhT1nhL9M1QGw3KQ90/view?usp=drivesdk Quote Link to comment Share on other sites More sharing options...
cowboy99 Posted March 23, 2018 Author Report Share Posted March 23, 2018 Don't think the T1030 had a series II. But again, Gerry S would be the man to ask. I.d certainly run any final results past him, he.s designed that XO Quote Link to comment Share on other sites More sharing options...
Pete B Posted March 24, 2018 Report Share Posted March 24, 2018 On 11/19/2015 at 11:50 PM, cowboy99 said: Thanks Gerry for the detailed response. I was afraid the. Two pair may not match up in a multichannel setup. One of each of larger electrolytic 120mfd caps in both the T1030s show signs of overheating (the leads overlapping body of cap have melted the plastic sheath/label) Still. It sure would be nice to have some documentation for these. Especially Thiel/Small parameters for the drivers in case I have replace them. I'd use Bennic NPE caps to replace all of the NPE types, the film cap is probably fine. I can measure T&S parameters but I don't have any of the drivers. Gerry says that the drivers are the same, yet they don't look the same? The T1000 woofers and mids look like Peerless (maybe the old CC line) and those in the T1030 look custom to BA, perhaps they cloned the performance? There's a pair of T1030's for sale in FL that I want, anyone making a trip from FL to the North East any time soon who can pony express them for me, LOL? Quote Link to comment Share on other sites More sharing options...
Pete B Posted March 24, 2018 Report Share Posted March 24, 2018 Charles, I bought both of the T1030 crossovers figuring that the circuit is common to one that I use and the inductors are probably close to what I use - I can wind them up or down for whatever I need. But if you want them I'll measure them and then we can work out a deal. One thing I noticed about the T1000 XO is that zobels are used where most designers are able to avoid them, the T1030 doesn't use them. I like the T1030 XO better. Quote Link to comment Share on other sites More sharing options...
Gerry S Posted March 24, 2018 Report Share Posted March 24, 2018 The T1030 crossover pictured above is a genuine BA part. It is a "quasi-second order" SERIES network between the woofer and midrange. With this type of network, any change in X-O values affect both the woofer AND the midrange SIMULTAINIOUSLY (because the drivers are effectively in series). It is much harder to "voice" because of this inter-dependent relationship. Note that If you disconnect either the midrange or woofer from the crossover, you will get no sound from either! The T930 Series 2 also used this "quasi-second order" configuration. I'm pretty sure the T830 Series 2 also used a quasi-second order network. The midrange and tweeters should be identical for the T930, T930 Series 2, T1000, T1000 Series 2 and T1030. There is NO "Series 2" T1030 (probably because it's hard to "improve" the T1030). Lessons learned from the T1030 development work resulted in the Series Two versions of the T930 and T830. Quote Link to comment Share on other sites More sharing options...
Pete B Posted March 24, 2018 Report Share Posted March 24, 2018 Gerry, I think you got those flipped, the T1000 that I have drawn above is series between the woofer and midrange. I've already traced out the T1030 pictured and it is not series. I don't like the series connection due to the interaction that you mention. Nice work by the way, I really admire the updated versions that compete with much more expensive speakers. Quote Link to comment Share on other sites More sharing options...
s sislane Posted May 1, 2022 Report Share Posted May 1, 2022 On 11/6/2015 at 10:14 AM, Gerry S said: Please refer to: Boston T1000 vs T1030 Started by morkys, Mar 16 2009 10:01 AM The T1000 and T1030 use identical drivers and enclosure volumes, but the crossovers are NOT interchangeable. The T1030's woofer was not identical to the T1000 woofer, it had a much larger magnet than the T1000 woofer, as well as a different basket. I don't recall if the coil & spider were different but believe they were. Â Quote Link to comment Share on other sites More sharing options...
moke66 Posted November 8, 2022 Report Share Posted November 8, 2022 Old topic I know, but those T1030 schematics still exist can someone share them? I'd like yo mskd z pair and see what it does for my T1000s Quote Link to comment Share on other sites More sharing options...
Pete B Posted November 28, 2022 Report Share Posted November 28, 2022 I drew the T1030 schematic a long time ago but I wasn't sure on the driver polarity for the mid and tweeter with regard to the wire colors and that's probably why I didn't post it here. I assume that the 2 red wires go to woofer + and two black wires to woofer -. Does anyone know how the mid and tweeter are wired? I'd like to get it right the first time I post. Tweeter:  Brown, and Yellow wires Midrange: Brown/White, and White wires Anyone know? Quote Link to comment Share on other sites More sharing options...
Pete B Posted November 28, 2022 Report Share Posted November 28, 2022 AudioKarma thread: https://www.audiokarma.org/forums/index.php?threads/help-need-help-with-this-crossover-schematic.789008/ Quote Link to comment Share on other sites More sharing options...
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