Hi guys,
I started my HiFi hobby in about 1978 with a pair of Realistic Optimus 5B speakers I bought with money from delivering newspapers. I soon sold those for Bose 601s, I was inexperienced. I became interested in DIY in the early 80s and sold the Bose to finance a Dynaudio build around 21W54 woofers and D28 tweeters. A nice improvement. Lately I started looking for the 5Bs to see just how far I progressed or just how much time and money I wasted. Today I started that re-evaluation with a $40.00 pair from facebook marketplace.
I hooked them up to the Onkyo 886 preamp and Ashly amp and sat and listened for a while. First impressions was "not bad". I put the mid and tweeter levels at the lowest setting. I attached a screen shot of the response with distortion. Bass and vocals sound open and smooth but highs sound like someone banging on a pie tin. tonal balance is bright and that's easy to see why. This is despite the measurements showing distortion on the highs to be very surprising low. I'm measuring mid and high distortion well under 1% at the given level. This is on par with my best tweeters but mostly 3rd order where the others are mostly 2nd.
Bass distortion is about as expected at above 1% rising to 6-7% about peaking at 10 times my favorite woofers.
I would put the frequency response at 38-18khz. Sens at 84db with the mids and highs at 89ish db. Not terrible for era, devices, cost and design.
Sound stage and imaging fall short of any other system in the house.
The plan is to give them a fair listen, dissect the crossover, match the levels and decide after that.
I started my HiFi hobby in about 1978 with a pair of Realistic Optimus 5B speakers I bought with money from delivering newspapers. I soon sold those for Bose 601s, I was inexperienced. I became interested in DIY in the early 80s and sold the Bose to finance a Dynaudio build around 21W54 woofers and D28 tweeters. A nice improvement. Lately I started looking for the 5Bs to see just how far I progressed or just how much time and money I wasted. Today I started that re-evaluation with a $40.00 pair from facebook marketplace.
I hooked them up to the Onkyo 886 preamp and Ashly amp and sat and listened for a while. First impressions was "not bad". I put the mid and tweeter levels at the lowest setting. I attached a screen shot of the response with distortion. Bass and vocals sound open and smooth but highs sound like someone banging on a pie tin. tonal balance is bright and that's easy to see why. This is despite the measurements showing distortion on the highs to be very surprising low. I'm measuring mid and high distortion well under 1% at the given level. This is on par with my best tweeters but mostly 3rd order where the others are mostly 2nd.
Bass distortion is about as expected at above 1% rising to 6-7% about peaking at 10 times my favorite woofers.
I would put the frequency response at 38-18khz. Sens at 84db with the mids and highs at 89ish db. Not terrible for era, devices, cost and design.
Sound stage and imaging fall short of any other system in the house.
The plan is to give them a fair listen, dissect the crossover, match the levels and decide after that.
Attachments
After reliving my youth with Frank Zappa, Beatles and Pink Floyd. I played around with the toe and found a much better balance by pointing the speakers straight ahead.
I have them 20" off the floor and away from the walls where my midbass speakers sit. Still not getting the soundstage and imaging a decent 8" two way delivers. Attached is a SEAS\Vifa similar to the Snell E. Since Dynaudio was my first DIY I always had an affinity for that design and built a poor man's version some years ago and still listen to that type of design daily.
The woofers are only 11" not the stated 12".
I have them 20" off the floor and away from the walls where my midbass speakers sit. Still not getting the soundstage and imaging a decent 8" two way delivers. Attached is a SEAS\Vifa similar to the Snell E. Since Dynaudio was my first DIY I always had an affinity for that design and built a poor man's version some years ago and still listen to that type of design daily.
The woofers are only 11" not the stated 12".
Attachments
Conclusion:
For what these are they're not terrible. I built worse and had\heard other vintage speakers that were well regarded but far worse. I would bet $20.00 there are expensive modern offerings that are not as enjoyable too.
Their short fallings are rough response and woofer distortion much greater than a modern 8" woofer.
Their strong suit is a nicely veneered box if well kept. Decent low frequency cut off.
For best unmodified use, pair them with a vintage receiver or other electronics with treble control. Work with positioning and toeing and tweak the treble for favored tone. Something we do anyways. Play the steamer, LPs, CDs enjoy the music and get on with life. That system would make a good conversation piece too. They'd do well in a coffee shop or other small public space looking for a vintage audio vibe. They are not for high level playback. I'll probably hang them in the garage.
A first level upgrade would be to redesign the crossover to better match levels and smooth out the response. With REW and a box of parts I'd say that'll take a few evenings and maybe $100.00 worth of good parts.
For all the time and effort of fixing these it might be better to leverage the nice looking box by replacing the baffle and plop in an 8" two or three way. Either from an original DIY effort, kit or copy of another's design. That''ll easily top $500.00 for new parts more or less depending on the design chosen. The wife might like them.
As for my original question: Did I build speakers that sound better than my first pair? Yes!! However, my first good design around the Dynaudio parts fell victim of foam rot about 25 years ago. these are working as intended after over 40 years and have a more life to go.
For what these are they're not terrible. I built worse and had\heard other vintage speakers that were well regarded but far worse. I would bet $20.00 there are expensive modern offerings that are not as enjoyable too.
Their short fallings are rough response and woofer distortion much greater than a modern 8" woofer.
Their strong suit is a nicely veneered box if well kept. Decent low frequency cut off.
For best unmodified use, pair them with a vintage receiver or other electronics with treble control. Work with positioning and toeing and tweak the treble for favored tone. Something we do anyways. Play the steamer, LPs, CDs enjoy the music and get on with life. That system would make a good conversation piece too. They'd do well in a coffee shop or other small public space looking for a vintage audio vibe. They are not for high level playback. I'll probably hang them in the garage.
A first level upgrade would be to redesign the crossover to better match levels and smooth out the response. With REW and a box of parts I'd say that'll take a few evenings and maybe $100.00 worth of good parts.
For all the time and effort of fixing these it might be better to leverage the nice looking box by replacing the baffle and plop in an 8" two or three way. Either from an original DIY effort, kit or copy of another's design. That''ll easily top $500.00 for new parts more or less depending on the design chosen. The wife might like them.
As for my original question: Did I build speakers that sound better than my first pair? Yes!! However, my first good design around the Dynaudio parts fell victim of foam rot about 25 years ago. these are working as intended after over 40 years and have a more life to go.