Apogee Duetta Signature 'buzz', another case

[WongKN]

I bought my Duetta Signature in 2010 and has been playing it happily since then. I had relatively little problems with it except for some distortion during very loud passages. As the cover was not very tightly held to the rest of the speaker, I just assumed that due to age, the mountings and possibly other internal stuff were loose. It wasn't a big problem happening only on a few LPs since I do not play very loud. This is because I sit very near to the speakers, a constraint due to room size.

A few months ago, I completed the upgrades to the rest of my system, in particular the tonearm and the catridge (a Shoedar and a Clearaudio). This improved the sound tremendously but unfortunately has one side effect, the 'distortion' grew worse. In particular, when I play James Taylor 'Handyman', both speakers would have a loud distorting buzzing sound in harmony with the bass line.

It was then that I started to research this issue of buzz with the Duetta Signatures in earnest. I have since learned a lot. Some of the info are actually not so good news to me. Anyway, over the long holidays (new year for the chinese, two weeks ago), I took out the two mounting screws at the bottom of the cover and for the first time, I removed the covers from the speakers to inspect the interior.

A quick check revealed that all screws are still nicely snug and there is nothing loose inside. But almost all the velco strips have came off from the cover's side. On the left speaker, one of the two 'hooks', actually allen head screws, have been screwed on too much so only one was supporting the cover. I have since turned that screw to make it same level with the other.

The ribbons seems to be pretty good condition. They are relatively clean but with a layer of fine dust and lint on the surface. Expect for what seems to be some 'fold-lines' on one of the tweeter ribbon, there are no creases or other damages to both bass and midrange ribbons on both speakers. Unfortunately I could see the beginnings of the 'peeling' or separation of the ribbon material to the backing material on one of the bass ribbons. However, they are still very minor at this moment. I suspect this could be due to the fact that the previous owner rarely played the speaker and then when it was left at his dealer to be sold, it sat there for a few years unplayed as well.

I have put the covers back on though I left the mounting screws at the bottom out. I have not replaced the velcro yet.

When I played James Taylor Handyman yesterday, to my surprise and delight, I could not hear any buzz anymore. The bass line was strong but clear and well defined. I was ecstatic.

Unfortunately, the joy was shortlived. Track four, Terra Nova, further down still created some buzz. It was quite low level but audible. So I next took out both covers and played the song but listened at near distance to both bass ribbons. I discovered that the buzz/rattle was coming from a very small portion of the ribbons at the lower corner facing the outer edge (i.e. lower left hand corner for left speaker, lower right hand corner for right speaker). I could clearly hear the metallic buzz there but not on other parts of the ribbon. (Horrors !) I lightly placed a finger to the ribbon on that part and the buzz/rattling stopped. So I confirm it was the ribbon hitting something.

So it looked like I had a combination of both the bass ribbon 'buzz' problem and the less disastrous loose cover problem. The loose cover I will take care of very soon, using new velcro. I am also thinking whether I should stick some foam to the cover so that it sits snugly into the main speaker frame.

For the ribbon problem, as there are lots of fine dust on the bass ribbon and lots of dust on the clamps, I intend to first clean them off, using one of those 'static' dusters used for electronic equipment. So I will lightly dust the ribbons and hope the duster will lift the dust off. Following the information/advice from one of the threads here ("checking your Apogee for aging"), I intend to take out the bottom clamp, clean it up (it is very very dusty and dirty) and replace the foam on it. I have not decided if it is wise to do so with the top clamp. I have also not decided if I want to do the 'foam on perpendicular surface of the vertical clamps' fix or not.

I am aware of the Graz ribbon replacements since 2010, a short while after I bought the speakers. One member of a local hifi forum that I am moderator of, in fact replaced the midrange/highs tweeter on his MiniGrand last year. For me, if (actually its WHEN) I replace the ribbons, I would prefer to do both. BUT I suspect I probably have to do the same thing as that MiniGrand member - i.e. replace just the midrange/high ribbon. Unfortunately it won't fix my buzz problem.

The reason why I say the above is simply due to geography and logistical constraints. I am from Malaysia which is in ASEAN. So my 'installer' is Graz himself. The issue for me is Shipping the speakers. The cost is going to be super expensive as I have to ship by air freight. Distance from Malaysia to Australia is very far as well. However, much much more of a problem is I simply DON'T have faith or trust on ANY of the local shipping agents. I am very good friends with my dealer, and I have seen several cases of damaged items from the shipping company, even when the holding crates are sturdy. The most painful one was the damage to one side of a pair of Wilson Audio MAXX speakers (mega-OUCH !!). So Graz WILL do a great job if I am to ship my speakers to him for refurbishing. But I fear by the time the shipping agent returns it to me, it might not be in the same condition.

Anyway, that is MY problem and I am still thinking and hoping there is a resolution for it in the near future (and hopefully Graz will still be offering the refurbishing service then).

Incidentally Graz, if you are reading this post, I did send you email a few days ago related to some enquiry on this issue. I have not received any response from you. The email id I sent to was the apogeeribbons one. I was quite long winded in that email as I wanted to explain everything. Hope I didn't unintentionally said anything wrong. I wonder if you have received the email.

To close off this post, if any member has any suggestions or comments, I will be very happy to hear from you. I checked the forum rules and discussion about this 'buzz problem' is encouraged. I know this topic has probably been beaten more or less to death but who knows, maybe there might be some new things still waiting to be discussed and I don't know of. I have been checking the old Audioworld forum as well.

Thanks for bearing with me and best regards,
WongKN

[Vansloneker]

Just a thought, can't you ship from Singapore?

Not to interfere with other peoples business but Graz works an hour a day on email. You will get a reply and a good one to I'm sure.

[Graz]

I look in here once a day and as Vans mentioned I limit myself to an hour a day on email! Life in 2012 is like working for amnesty international - we are all writing 100 letters a week!!!

I will reply by close on Monday.

Take care - Graz

[WongKN]

Thanks for the responses. I live in Kuala Lumpur, the capital and it is around 200miles between here and Singapore. Then from Singapore, I still have to fly it to Australia. In one of the old audioworld threads, there was an amusing post by one person who was talking about flying to Australia and then taking the speakers along with him. I have a friend who will be a PR in Australia in a couple of years and I might just do that then. Hopefully the speakers are not too badly done in by then !

Unfortunately there is no installer nearer where I don't have to fly. I don't mind driving the 200 miles or more. So it is quite frustrating. Having Graz do the work would be the most preferred option of course and I get that option here. But how to fly 300 lbs of speakers 6000km (4000miles) with an agent I don't feel comfortable with ?

Anyway, again this is really my own personal problem and I hope to get some progress in the near future.

I hope this thread has been of interest to some.

Also another interesting info is that I recently had a look at the insides of another pair of Duetta Signatures, belonging to my friend, the ex-Apogee dealer here. I have been reading the issue of wrong/misleading labelling of the crossover inductors for the DS. My own unit has this wrong info - the bass inductor is labelled 2.8mH, the midrange on 3-9-4.0 mH. Interestingly my friend's unit has correctly labelled inductors. The large cardboard spool inductor is labelled 2.22mH. For the midrange inductor, the tape is wrapped around one of the wires in the coil. On the reverse side, it was written 6.3mH. I will upload a photo I took of the bass inductor later here. My friend's unit is manufactured in 1994, according to the date written on the top clamp.

[LIVE_EVIL]

no need to fly anything.
Your biggest expense would be building proper crates for duetta.
then just seafreight it.
sea freight is amazingly cheap compared to other transportation options. it is longer of course but not by too much.
So just find freight forwarders from your nearest port to australia.

[WongKN]

That is an interesting point indeed. I will wait for response from Graz (take your time, I do understand the stress of having mountains of emails) and then decide what to do from there. Thanks for the suggestion !

[WongKN]

Here is the photo of my friend's Duetta Signature. The bass inductor is on the lower left hand corner and it is marked as 2.22 mH. We can't see the tape on the MRT inductor in this photo but it is written 6.4 mH.