what type of solder do you use...it seems to flow well...I have little experience soldering but getting better...I'm using mundorf silver solder...is that good?...
Not being familiar with audio but thought worthwhile asking, on some modern automotive plugs the pins can be replaced, not an option on these? The capacitor testing was enlightening....
I have a pair of 551 and love them. I’ve never even used a soldering iron before but I’m ginning up to recap the crossover and I’m wondering: since I have replaced the tweeters with a pair of Morel 448, should I lower the tweeter crossover to fill in the hole between its response and that of the midrange? If so is it super hard to do?
You can't make crossover adjustments without measuring the speakers. You won't get the integration correct. You might end up with phase issues causing dips or peaks. The tweeters in these play really high so it's probably difficult to hear any issues. Plus you can vary the output level. If the morels nominal impedance is similar to the original HF2001 then your probably not a million miles off. I'd stick with original cap values unless you can get them measured and tweeter circuit adjustments are needed?
any advice on cleaning the pots?They’re quite crackly on the pair I recently acquired and the circuit is broken when the dial is turned to certain points. You mention deoxit - how do you apply it?
@@tulikeidar8717 Spray it through the vent holes and keep rotating the pot to work it into the contacts. It works really well and I measured a smooth resistance sweep after on all 4 pots
What is the cut off frequency for using film capacitors would you say Matt? Say you have a largish two way crossed over at 3000hz. Would it become problematic? As opposed to 5000hz?
Hi. I'd always use film caps for the tweeter circuit especially in a 2way as there in the critical signal path. The woofer in a 2way will have inductors in the critical path. The capacitors will be in shunt down to ground so I'm not bothered really if there bi-polar electrolytic type. Depends greatly on the speaker really. Polys where possible especially on the HF. A lot of 2ways are crossed at 3kHz as you note. 5kHz is a bit excessive unless the woofer is tiny. The 5kHz region would be 3way territory. Hope that helps
@@haycrossaudio5474 Thanks. I was just wondering it might get harsh when tweeters are getting closer to mid range frequencies in general. I have some speakers crossed over at 5000hz with 6 inch woofers. Vifa D19td tweeters (actually a Seas and a Vifa, one was replaced probably the ferrofluid, originally 2x seas but they look identical). Not tiny 38.5x24wx20/21d cm. Haven't seen the crossover yet. (look up "BNS 232" if you are interested. They are dutch).
@@D1N02 A decent tweeter should be able to play down to at least 2.5kHz. Asking a large woofer to do that is a bit bonkers in my view. Also as the wavelengths get near to the driver diameter the driver will beam and off axis will be compromised. I think some designers run the woofers up high to avoid crossing in the upper midrange which I can understand. The 2-4kHz region is a sensitive area for our hearing. If polys are integrated properly then they shouldn't be harsh. They should be detailed. The Talisman speakers I redesigned are a case and point in that. They sound fantastic. Crossed ar 1.9kHz using SOLEN polys.
@afico6172 Yes if the fuse was blown the tweeter would not work at all. Could be the tweeter failing, crossover issues, issues with the L-Pad adjustment pot. Unfortunately the only way to know is to have the speaker here
Very informative thanks>
Just got picked up a pair of these and considering recapping them.
Would love to hear the reconditioned test and see results.
what type of solder do you use...it seems to flow well...I have little experience soldering but getting better...I'm using mundorf silver solder...is that good?...
Not being familiar with audio but thought worthwhile asking, on some modern automotive plugs the pins can be replaced, not an option on these?
The capacitor testing was enlightening....
what is the padding w/ adhesive backing for the capacitors called...so I know what to search for online?
I have a pair of 551 and love them. I’ve never even used a soldering iron before but I’m ginning up to recap the crossover and I’m wondering: since I have replaced the tweeters with a pair of Morel 448, should I lower the tweeter crossover to fill in the hole between its response and that of the midrange? If so is it super hard to do?
You can't make crossover adjustments without measuring the speakers. You won't get the integration correct. You might end up with phase issues causing dips or peaks. The tweeters in these play really high so it's probably difficult to hear any issues. Plus you can vary the output level. If the morels nominal impedance is similar to the original HF2001 then your probably not a million miles off. I'd stick with original cap values unless you can get them measured and tweeter circuit adjustments are needed?
I almost bought a pair of 551's 2 months ago.
This series is incredibly useful thank you! Got a part 3 coming?
any advice on cleaning the pots?They’re quite crackly on the pair I recently acquired and the circuit is broken when the dial is turned to certain points. You mention deoxit - how do you apply it?
@@tulikeidar8717 Spray it through the vent holes and keep rotating the pot to work it into the contacts. It works really well and I measured a smooth resistance sweep after on all 4 pots
What is the cut off frequency for using film capacitors would you say Matt? Say you have a largish two way crossed over at 3000hz. Would it become problematic? As opposed to 5000hz?
Hi. I'd always use film caps for the tweeter circuit especially in a 2way as there in the critical signal path. The woofer in a 2way will have inductors in the critical path. The capacitors will be in shunt down to ground so I'm not bothered really if there bi-polar electrolytic type. Depends greatly on the speaker really. Polys where possible especially on the HF.
A lot of 2ways are crossed at 3kHz as you note. 5kHz is a bit excessive unless the woofer is tiny. The 5kHz region would be 3way territory. Hope that helps
@@haycrossaudio5474 Thanks. I was just wondering it might get harsh when tweeters are getting closer to mid range frequencies in general.
I have some speakers crossed over at 5000hz with 6 inch woofers. Vifa D19td tweeters (actually a Seas and a Vifa, one was replaced probably the ferrofluid, originally 2x seas but they look identical). Not tiny 38.5x24wx20/21d cm. Haven't seen the crossover yet. (look up "BNS 232" if you are interested. They are dutch).
@@D1N02 A decent tweeter should be able to play down to at least 2.5kHz. Asking a large woofer to do that is a bit bonkers in my view. Also as the wavelengths get near to the driver diameter the driver will beam and off axis will be compromised. I think some designers run the woofers up high to avoid crossing in the upper midrange which I can understand. The 2-4kHz region is a sensitive area for our hearing.
If polys are integrated properly then they shouldn't be harsh. They should be detailed.
The Talisman speakers I redesigned are a case and point in that. They sound fantastic. Crossed ar 1.9kHz using SOLEN polys.
Hello i have a tweeter that sounds softer than the other one . What fan I do ?
@@afico6172 Have checked the fuse on the front? It might not be working at all
@@haycrossaudio5474 no..but if it is a blown fuse the tweeter should not work at all or am i wrong?
@afico6172 Yes if the fuse was blown the tweeter would not work at all. Could be the tweeter failing, crossover issues, issues with the L-Pad adjustment pot. Unfortunately the only way to know is to have the speaker here