cerwin vega hed u-15

[uncle stinky]

I just picked up a pair of hed u-15's. Is anyone a fan of these or an owner as I have found little info, thank you

 

[Horn Head]

Here's Info

Check out 1980 brochure in this thread for info.

http://www.audiokarma.org/forums/showthread.php?t=280394

 

[Daniel Shobe]

I just picked up a pair of hed u-15's. Is anyone a fan of these or an owner as I have found little info, thank you

good speakers 101db eff. good bass

 

[Retrovert]

In certain jurisdictions the HED-15 must be registered as a destructive device.

I own a pair of U123 HED (original owner, which was foolishness), which are a 12 inch three-way, ported cabinet. Fine for rock and roll, but not much else. I describe these as the finest vinyl coated MDF money could buy! If by "finest" one meant "ported speaker" and by "money could buy" one meant "for $200 in 1982". Which was real money. About $600 in today's inflated currency.

The existing crossover likely is the same as the other HED units, i.e. electrolytic capacitors and iron-core inductors. The baffle is non-chamfered, and the cabinet (as I remember from decades ago) was not lined to reduce reflections, and the stuffing was inadequate to tame the boomyness.

Might be worth considering ripping out the crossover and replacing it with a from-scratch version using decent inductors and film capacitors. In any event, the electrolytics will be degraded and will muffle the sound.

 

[Welderman84]

I have a set of HED U15s also, just bought some factory crossovers that appear better than mine at least, and a can of deoxit. How would i get a modern better crossover that would fit exactly as these do? Or whats the procedure? Please and thank you.

In certain jurisdictions the HED-15 must be registered as a destructive device.

I own a pair of U123 HED (original owner, which was foolishness), which are a 12 inch three-way, ported cabinet. Fine for rock and roll, but not much else. I describe these as the finest vinyl coated MDF money could buy! If by "finest" one meant "ported speaker" and by "money could buy" one meant "for $200 in 1982". Which was real money. About $600 in today's inflated currency.

The existing crossover likely is the same as the other HED units, i.e. electrolytic capacitors and iron-core inductors. The baffle is non-chamfered, and the cabinet (as I remember from decades ago) was not lined to reduce reflections, and the stuffing was inadequate to tame the boomyness.

Might be worth considering ripping out the crossover and replacing it with a from-scratch version using decent inductors and film capacitors. In any event, the electrolytics will be degraded and will muffle the sound.

 

[Retrovert]

I have a set of HED U15s also, just bought some factory crossovers that appear better than mine at least, and a can of deoxit. How would i get a modern better crossover that would fit exactly as these do? Or whats the procedure? Please and thank you.

A crossover is an electrical filter designed for specific frequencies, and a mass-market crossover may not have the appropriate frequencies or may have filters which are unsuitable because of steepness of slope which controls how effectively the filter removes out-of-band signal. The formulas for the filters are well known, and all over the interwebs. I have elsewhere included the math and examples. Crossover filters are constructed using capacitors for high-pass and inductors for low-pass; two such filters may be combined to form a band-pass. A low-pass for the woofer, a high-pass for the tweeter, and a band-pass for the midrange. The principles are easily understood.

A crossover may be constructed using quality, but inexpensive, polypropylene capacitors and air-core inductors; higher-quality cored inductors, which I have elsewhere described, may be used for budgetary reasons.

A book on speaker design, some of which I have elsewhere discussed, will explain the issues.

 

[f0427ea]

heres a U-15 crossover ,air core inductor and polypropylene film capicators , silver wires just like any other CV crossover of this vintage .
get the pot and circuit breaker cleaned / working as they should and it should be fine as is or you could re-cap it if you feel the need.

 

[f0427ea]

I have a set of HED U15s also, just bought some factory crossovers that appear better than mine at least, and a can of deoxit. How would i get a modern better crossover that would fit exactly as these do? Or whats the procedure? Please and thank you.

see above post