Dynaudio C1 II owners - how loud can you go?

Hi All,

I just had a question regarding the review of the Dynaudio C1 II's here: http://www.tonepublications.com/review/dynaudio-confidence-c1-ii/

Jeff mentioned that with the right amount of power, the speakers never run out of headroom. I bought a pair last year and connected them them to a Peachtree Nova220SE (class D - yes, but it's rated 350w at 4ohms). I download and stream a lot of digital music off my mac with itunes+amarra or via tidal, and this amp made sense - I listen to this setup in my bedroom and don't have a lot of room for separates.

My question for the forum is, do these have a problem when playing loud? I can't seem to get more than 10-11 o'clock on the volume control on the peachtree with bass heavy tracks before I hear a high pitched "pop" (almost a bird like "tweet") and have to lower the volume. Does anyone else have this problem? If so, were you able to correct the problem by swapping amps, cables, etc? Am I just expecting too much from these speakers?

Don't know about your case specifically but for comparison I have 500w/ch Bel Canto ref1000m Class D that run my Dynaudio Contour 1.3mkII and other speakers I own. These Dynaudios like every bit of power you can through at them. I have yet to practically reach the point where either speakers or amp sound stressed in any way, and I listen quite loud on occasion.

My guess is your Dyns have better low end extension and that combined with teh C1 85db sensitivity that I read ups the ante for power exponentially as the frequency gets lower. More like my OHM F5s in that regard. The OHMs also like every bit of that power, and they read to be somewhat more efficient than the Dyn C1s.

So I suspect you need an amp with even more power into 8 ohms doubling into 4 to get all of what the speakers are capable of. Build quality on these Dyns is top notch, so unless damaged or defective, I doubt they are malfunctioning, though their power needs could be the source of teh problem.
The severity of teh problem as you describe could likely indicate a defect or problem somewhere with teh gear or their conenctions. First thing though I would check all wires and connections as well to make sure there are no shorted connections etc.

I did have a malfunction in one of my amps (defective input buffer circuit board) once that resulted in distorted sound along the lines you describe. It could well just be that the amp has a defect. Do you have any other speakers or amps to try to see if similar problems? Is problem the same in both channels? if not does the sound switch to other speaker if you switch r/l output from amp?
Mapman gives good advice. I doubt that the problem lies with your speakers. If possible, you should see if a local audio dealer would be willing to loan you a high powered integrated to take home for a day to see if the problem is the Peachtree.
I used to have a pair of c1"s, not the II version. I used a Simaudio i7 integrated amp. They played quite loud without any distortion. My room size is 18x12x8. Perhaps your amp is giving you a problem.
In answer to your last question- if your room is not too big, it would be hard to ask "too much from these speakers".

Considering the scenario of heavy bass, loud volume, and a "pop", I'm thinking "bottoming out" of a woofer in one of the speakers. This occurs when there is extreme excursion of the woofer cone, and the voice coil hits the back of the pole structure. If this is the problem, you have reached the limit of the speaker's performance for bass reproduction, and a different amp will not solve the problem. The solution would be to add a subwoofer with high pass to the main speaker, or use a different speaker.
Thanks all. I'll be swapping out some components and cables in the coming weeks and will report back with findings. I'll give Dynaudio a call if it still occurs after eliminating all other sources and see what they have to say.

I did email Jeff at Toneaudio and he responded thinking it's the amp clipping. I honestly don't think I'm pushing these speakers too hard. When this "issue" happens, I have it loud but it's not anywhere near what I'd call crazy or ear bleeding. My room is around 13x16x9 - so I'd think these speakers could pressurize the space without any trouble based on reviews and your comments. I've had much cheaper speakers at much louder volumes. For what I paid for these speakers, I'd expect so much more.
Derek, I have C1, not the II, they are driven by Octave V110. Do not expect them can be played loud, if you listening to Jazz, yes, you can play them louder, if you listen to some high dynamic music, don't play them too loud, you could damage them! unless you feed them with a amp have 1000W. Original C1 can be played louder than the C1 II, But C1 II sounds better at lower volume than C1. Xti16 has compared C1 and C1 II Sig side by side in his house, driven by Octave se75, he said C1 II bottomed out earlier than C1. But C1 needed to play a bit louder to come alive.
+1 TLS... almost certain
A couple of years ago another member had a similar symptom. But he described it as a screech/scratching sound in the mids (vocals). He also had a V70SE (by that time I upgraded to the V110). He contacted Dynaudio and they thought it was a problem with his V70SE. They gave him a sweet deal on a new V110. When it arrived same problem. He said he took the C1's to his local dealer who confirmed the speakers caused it. Turns out both woofers coils had swollen up and were rubbing. This only happened at high volumes with bass heavy tracks and affected mostly female vocals.

If that is the case what you can try is with the system off push the woofer drivers by hand and both listen and feel for smooth movement. If you hear a scratchy sound or feel uneven movement the coils could have swollen.

That person bought his C1's used and really had no idea how the original owner used/abused them. I never found out if he had them repaired or just gave up on them.

To me it sounds like the woofers are bottoming out. When I had either the original C1's or MKII/Sig the bottoming out was a POP kind of sound. I personally heard that and made sure I never turned it up that loud again. It also happened with music that was very compressed.
I have a Nova pre / 220 amp combo and if it has similar power to your Nova 220se, 11 o'clock is pretty loud...

I've got Monitor Audio GX50's that have the same 86db sensitivity rating as your Dyns and I don't turn it up past 10 and usually listen at 8 or 9...

how big is your room?