Site Links
Howdy, Stranger!
It looks like you're new here. If you want to get involved, click one of these buttons!
Quick Links
Categories
Please review the site Rules, Terms of Service, and Privacy Policy at your convenience. Rules, TOS, Privacy
Get familiar with the reaction system: Introducing the Reaction System
Bose 201 Series IV
Yep, you read that right - a teardown/build quality review of the infamous Bose 201.
To start with, the cabinets are 1/2" particle board. Vinyl wrapped. No bracing. Plastic slot port. Paper cone "tweeter". Untreated paper cone woofer with a treated foam surround. The suspension is very stiff on the woofer, but it does have an attractive trim ring. The woofer otherwise has a very old school look to it. The terminals are solderless wire-wrapped type - a fairly legitimate method for terminating. The internal wiring appears to be 24awg solid core, and the crossover consists of a single capacitor. There is what appears to be about 4-5oz of stuffing, actually fairly high quality material. Some type of resistive element in the "crossover" - not sure if it is a protection device or what. I really don't give a shit, either. These are seriously shitass quality speakers.
Pushing on the woofer cone introduces wrinkling in the surround almost immediately. Not a good sign for linearity, but probably moot if these are used in some kind of 5.1 system where the receiver will make sure this do not see much bass action.
Woofer parameters are:
There we see it has a respectable Qts and a low compliance - and is very sensitive for a 6.5" driver. Hoffman is in the mix here, though, as the small vented box does not yield any extension. Some wrinkles around 700Hz leads me to believe the response is not very linear. In fact, there are wrinkles all the way from 700 up to 8K if you look.
I estimate the usable interior of the cabinet at around 8.5 liters. It appears to be tuned to around 70Hz, and the system impedance is fairly benign:
If going by the approximate 70Hz tuning, this is the modeled response:
So far it lives up to the "no lows" reputation. Pay no attention to the Rival header, nothing to see here. I'm remarkably lazy, to be honest.
I'll put some response measurements up later. I might even do some listening.
To start with, the cabinets are 1/2" particle board. Vinyl wrapped. No bracing. Plastic slot port. Paper cone "tweeter". Untreated paper cone woofer with a treated foam surround. The suspension is very stiff on the woofer, but it does have an attractive trim ring. The woofer otherwise has a very old school look to it. The terminals are solderless wire-wrapped type - a fairly legitimate method for terminating. The internal wiring appears to be 24awg solid core, and the crossover consists of a single capacitor. There is what appears to be about 4-5oz of stuffing, actually fairly high quality material. Some type of resistive element in the "crossover" - not sure if it is a protection device or what. I really don't give a shit, either. These are seriously shitass quality speakers.
Pushing on the woofer cone introduces wrinkling in the surround almost immediately. Not a good sign for linearity, but probably moot if these are used in some kind of 5.1 system where the receiver will make sure this do not see much bass action.
Woofer parameters are:
Fs = 81.03 Hz
Re = 5.83 ohms[dc]
Le = 445.56 uH
L2 = 1467.20 uH
R2 = 41.05 ohms
Qt = 0.45
Qes = 0.49
Qms = 5.85
Mms = 14.51 grams
Rms = 1.263177 kg/s
Cms = 0.000266 m/N
Vas = 7.43 liters
Sd= 141.03 cm^2
Bl = 9.373125 Tm
ETA = 0.77 %
Lp(2.83V/1m) = 92.37 dB
Added Mass Method:
Added mass = 30.00 grams
Diameter= 13.40 cm
Woofer impedance curve:
Woofer impedance curve:
There we see it has a respectable Qts and a low compliance - and is very sensitive for a 6.5" driver. Hoffman is in the mix here, though, as the small vented box does not yield any extension. Some wrinkles around 700Hz leads me to believe the response is not very linear. In fact, there are wrinkles all the way from 700 up to 8K if you look.
I estimate the usable interior of the cabinet at around 8.5 liters. It appears to be tuned to around 70Hz, and the system impedance is fairly benign:
If going by the approximate 70Hz tuning, this is the modeled response:
So far it lives up to the "no lows" reputation. Pay no attention to the Rival header, nothing to see here. I'm remarkably lazy, to be honest.
I'll put some response measurements up later. I might even do some listening.
I have a signature.
Comments
Sold them for more than I paid...
Couple surprises here to me, the distortion above 1.5K is actually quite acceptable - across the entire band, even. I have measured worse from brands you would recognize.
In this gated measurement, the red is square on-axis with the woofer. The yellowish is square on axis with the tweeter, and the silver is in-between meaning both drivers are off-axis. Read into it what you will - these were taken quickly at about 1M:
I tried listening, but the complete train wreck that is the enclosure makes everything sound horrible. I should have grabbed a waterfall, I'm sure there is a ton of ringing not captured in the response measurements.
Here's my thoughts on these: if someone has no speakers and is offered a pair of these, they would be worth tinkering with. I imagine the experience would be decidedly better if someone were to reinforce the plastic housings the tweeter is mounted to with some dope (or just get really fucking high before listening), a brace or two inside, and listen to it on the tweeter axis (yellow curve) with a bit of EQ to bring the treble down. Definitely not worth the asking price IMHO, but all in all, there is some potential there. They are fairly flat to 1K covering most of the fundamentals in everyday sounds/music and I would bet experimenting with placement angle would yield an overall flattish first response.
OK, got that out of the way. I also have the "matching" center channel. That is a weird looking thing.
Ive never heard speakers with hard plastic enclosure pieces like that that don’t sound like speakers in a hard plastic enclosure. As you mentioned I bet some 3m strip caulk could work wonders. They probably could be a minimally acceptable speaker in a real enclosure.