Free Shipping on All Orders 1-866-764-1801

Vist our Online Store
+ Reply to Thread
Results 1 to 5 of 5
  1. #1

    Member Sales Rating: (0)

    Join Date
    May 2006
    The Seasonally Frozen Wastelands

    Default Another inductor thread--The Little Guys

    I'm torn between tacking this into an existing inductor thread and derailing it...or starting yet another thread and maybe duplicate a lot of what's been covered already.

    ALL of the recent inductor replacement discussion is with the one-per-cabinet, large inductor on the ground side of the SDA drivers...right? For the newer speakers, this seems to be the same value inductor--16 mH; but on my SDA 1B it's listed as 9.6 mH.

    Nobody is playing with the much smaller inductors in the tweeter circuits (often .4 or .7 mH); or the inductor on the + side of the mid-woofers--typically 1 to 2 mH?

    It'd be easy enough--and not so expensive--to replace the tweeter and MW inductors, I get the sense that there's various reasons (of which I am ignorant) to NOT change them. Correct? If not, and if an "audiophile approved" inductor change will improve the sound quality...I have some interest in replacing a .4 mH inductor that drives the top tweeter in my 1Bs, while leaving the existing .4 mH which in combination with a resistor, bleeds current off directly to the - terminal. Lower DCR in the tweeter-driving inductor would boost the tweeter volume slightly, and in my case that'd be a good thing: I'd hope for a clarity improvement as well. Lower DCR in the second inductor would bleed more current, tending to reduce the volume of the tweeters, and making life more difficult for the amp. Would replacing one but not the other "unbalance" the high-frequency crossover? Do those inductors need to have near-identical characteristics for some reason?

    I don't know what to think about the small inductors in the + side of the MW circuits.
    Last edited by Schurkey; 10-14-2011 at 05:39 PM.

  2. #2

    Member Sales Rating: (5)

    Join Date
    Oct 2007
    Pensacola, Florida


    This would be an interesting discussion if anyone has experience replacing the smaller inductors. I'm awaiting a few parts (and some time) before starting the Gimpod XO rebuild, Larry's Rings, Spikes, I/C upgrades and have thought about building a complete XO and keeping the old ones as backups. I realize inductors don't 'wear out" per se but thought it might be worth exploring before I start. Any input / thoughts on the smaller inductors would be appreciated.
    Sony 60'' SXRD 1080p
    Amp = Carver AV-705THX 5-Channel
    Processor = NAD T747
    Panasonic BD35 Blu-Ray
    Main = SDA-1C Studio with RD0s, spikes, XO rebuild, rings, I/C upgrade
    Center=Polk CS10, Surround = Athena Dipoles, Sub= Boston 12HO
    Music/Video Streaming = Netgear NEO550
    TT = Audio Technica

  3. #3

    Member Sales Rating: (0)

    Join Date
    Nov 2007
    Knoxville, TN


    The objective to replace the large SDA inductor is lower DCR, more low bass control, and better cone damping by tighter coupling the drivers to the amp. The small inductors have fairly low DCR so there is little to be gained by changing them. Plus there is a risk of changing the XO point or the XO output in a bad way.
    '65 427 Shelby AC Cobra
    '72 Triumph TR-6
    '88 Polk SDA SRS 1.2, with upgraded XO caps and Erse SDA inductors
    '86 Polk SDA CRS+
    '84 Polk Monitor 10A (Peerless tweeters)
    '05 HSU VTF-3 Sub
    '93 Carver TFM-35 (just because)
    '88 Carver M-1.0t (just because)
    '14 PGA2310 based custom remote volume control
    '88 Adcom GFP-555
    '88 Adcom GFA-555 (upgraded/restored)
    '05 Onkyo DV-555 media
    '89 Pioneer Laser Disc media
    '89 Sony SuperBeta HiFi media

  4. #4

    Member Sales Rating: (1)

    Join Date
    Oct 2008
    Descending toward the moon in the CLEM (Chinese Lunar Excursion Module), looking for Chang'e


    Would the Big Guys be Sherlock Holmes-like "Deductors", then? Just kidding guys! I couldn't resist because the lingo is so Techie and I'm a bit sleep-deprived.

    Onkyo TX-SR 805 System #1 HT AVR
    Office Two Channel: LSi-7s (Nakamichi CA-5, NAD 214, Pioneer BDP51fd)
    Vintage Polks: Polk Monitor 5As, Monitor 7Bs [HK 730], Monitor 10As [Marantz 2265], SDA-2Bs [Jolida JD-303, Jolida MV-MK4]
    Headphones: HD600, Q701, ATH-M50s etc. Bravo Audio Ocean amp., Onkyo P-304, Adcom GFA-555, Technics Direct Drive TT

  5. #5

    Member Sales Rating: (0)

    Join Date
    May 2006
    The Seasonally Frozen Wastelands


    For what it's worth: ERSE is offering to CUSTOM UNWIND inductors to achieve the specific inductance you want. Bear in mind that my 1Bs use a 9.6mH inductor where the newer units use a ~16-something mH inductor.

    From two e-mails I received from them:

    If you order 2 ESQ55-16-10000 we can dewind them to exactly 9.6mH for a $10 each fee.
    Can you send us the inductors ? We can offer you an EXACT DCR reading. Handle held meter will not offer a TRUE DCR Reading.

    Generally the lower DCR between the amp and actual driver the better. This offers a lower Q not just low DCR. So not only will you get more efficiency but better control. The amplifier will couple better to the driver giving better performance. In a nut shell with series inductors try to get rid of DCR wherever possible.

    We offer the dewinding to all customers ok to post. Just need to integrate the de winding option into our site.

    Best regards,

    The ERSE Audio Sales Team
    website :
    Placing my order soon. I think I will NOT take them up on the custom de-winding so I can tune by ear, but others might disagree.

    Remove about 5 turns to get 9.6mH.

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)


Similar Threads

  1. Need Help I'm going for the Inductor Upgrade!
    By audiocr381ve in forum Vintage Speakers
    Replies: 33
    Last Post: 10-07-2011, 08:35 AM
  2. Need Help SRS inductor placement
    By dcoil in forum Vintage Speakers
    Replies: 17
    Last Post: 09-22-2011, 03:17 AM
  3. Replies: 2
    Last Post: 08-07-2011, 10:52 PM
  4. Need Help Inductor gauges 12,14,16?
    By RandyWilliamson in forum Vintage Speakers
    Replies: 8
    Last Post: 12-10-2008, 01:04 PM
  5. Guys, please check this thread out. Funny stuff :D
    By tortie in forum The Clubhouse
    Replies: 4
    Last Post: 10-21-2003, 09:39 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts