I’m sure you’re right, I might be getting a little obsessed... 😀
I think I will do the test, it’s complicated somewhat by having an active 4 way system in the car but I’ll think of something.
I had been using a Sony XM2501 in lieu while I had it on the Soundstream on the bench and it definitely sounds worse, I got my other half (who had better eats than I do) confirm, as did my mate who is also into old school hifi.
I also have a Phoenix gold M100 coming to try out as well, I shall report back...
I think I will do the test, it’s complicated somewhat by having an active 4 way system in the car but I’ll think of something.
I had been using a Sony XM2501 in lieu while I had it on the Soundstream on the bench and it definitely sounds worse, I got my other half (who had better eats than I do) confirm, as did my mate who is also into old school hifi.
I also have a Phoenix gold M100 coming to try out as well, I shall report back...
Don't do it in the car. Do it on the workbench with some nice home speakers. Solid state amplifiers that use global feedback (virtually 100% do) should sound identical if there are no tone or crossover components in the circuit (all bypassed) and the gains set the same.
Ok, I have a set of Martin Logan ESL electrostatics and a set of Orpheus Aurora 3 conventional speakers as my “nice” stuff at home, a set of Quad electrostatics and some KEF surround type speakers to try depending on what you think best?
I like the sound of electrostatics, prefer them in fact, but am aware they can present a low impedance load at the frequencies I’m interested in testing, will that affect things?
I like the sound of electrostatics, prefer them in fact, but am aware they can present a low impedance load at the frequencies I’m interested in testing, will that affect things?
Also, how quiet does the power supply need to be for critical listening in the home with a car amp?
I’m not sure how quiet a car alternator is but I imagine quite noisy, then again SQ systems are generally judged on the battery?
I’m not sure how quiet a car alternator is but I imagine quite noisy, then again SQ systems are generally judged on the battery?
All of those are well out of my budget. You'll have to choose what's best or someone else will have to advise but I guess I'd stick with conventional speakers.
See also 45.
There is virtually no way to have a power supply noisy enough to get into the audio. The power supply in a car is terrible and if the amp and signal grounds are right, none of it gets into the audio.
There is virtually no way to have a power supply noisy enough to get into the audio. The power supply in a car is terrible and if the amp and signal grounds are right, none of it gets into the audio.
Ok, I’ll try them with the Orpheus speakers first and experiment from there.
I lucked on to everything I bought second hand and frequently in need of repair, the Quad ESL63s in particular were a bargain. I paid 200 dollars for a set that someone had allowed to arc out on one of the midrange panels. The replacement panel was about 80 dollars and if paired with appropriate stereo subwoofers, are as good as the Martin Logans. They won’t play as loud but have the best midrange And treble of pretty much Any speaker out there.
They turn up eBay quite often if you keep an eye out. I also have some spare panels I could send you as a thank you for all your help should you decide to get a set. 🙂
I lucked on to everything I bought second hand and frequently in need of repair, the Quad ESL63s in particular were a bargain. I paid 200 dollars for a set that someone had allowed to arc out on one of the midrange panels. The replacement panel was about 80 dollars and if paired with appropriate stereo subwoofers, are as good as the Martin Logans. They won’t play as loud but have the best midrange And treble of pretty much Any speaker out there.
They turn up eBay quite often if you keep an eye out. I also have some spare panels I could send you as a thank you for all your help should you decide to get a set. 🙂
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Cool, I have a high current 12 v transformer I could fit with a rectifier and put some cap banks on to make a beefy supply. Should be better than my chopped up ATX supply which cuts out on bass transients anyway.
Switching the crossover in and out today caused it to put enough dc out on the right channel to blow the voice coil of my vintage MB Quart 4” midrange...
I give up on this amp and am sending it away for repair or disposal...
F@&k...
I give up on this amp and am sending it away for repair or disposal...
F@&k...
The very same, Gordon was very good on the phone earlier while I ranted and raved about the quality of Soundstream switch gear...
I hope the accountant who spec’ed them has to s&@t a hedgehog backwards.
He mentioned something t amp possibly being under biased and hence sounding splashy, I’m going to get him to do a full restore.
If the amp still sounds bad after all of this I’m going to find out where the designer lives and leave a trenchant review on trip advisor...
I hope the accountant who spec’ed them has to s&@t a hedgehog backwards.
He mentioned something t amp possibly being under biased and hence sounding splashy, I’m going to get him to do a full restore.
If the amp still sounds bad after all of this I’m going to find out where the designer lives and leave a trenchant review on trip advisor...
The switches are old. They were coated with silver which is a very good conductor but it oxidizes. Add to that that some are not self cleaning and that compounds the issue. You can't expect everything to last forever.
The OEM switches that were not exposed to the elements were still perfectly fine up to a few years ago when you could still buy them.
If the amp doesn't sound right to you, either your amp is defective or many thousands of people who love SS Amps have tin ears.
The OEM switches that were not exposed to the elements were still perfectly fine up to a few years ago when you could still buy them.
If the amp doesn't sound right to you, either your amp is defective or many thousands of people who love SS Amps have tin ears.
All you say is true but I loved those MB Quarts, the sounded fantastic compared to most modern, high power handling, high moving mass, long excursion drivers and this damn thing killed one of them...
I feel confident in pronouncing it defective and obviously beyond my abilities to fix, I do note with some small annoyance that the Phoenix Gold amps of the same era I have don’t have as crappy switches and still work just fine.
Hell, even the Sony, clarion, alpine, pioneer and other mid fi amps I have don’t suffer from this “flick a crossover switch, a fecking crossover switch, and have a blast of dc” syndrome...
Until Gordon delivers a miracle I’m going g to damn Soundstream and their lineage right down to the ores the materials were refined from...😡
I still want a Reference 200S though, no f£&king switches on that one...
And. Goliath tarantula, really want one of those too..
😱😱
I feel confident in pronouncing it defective and obviously beyond my abilities to fix, I do note with some small annoyance that the Phoenix Gold amps of the same era I have don’t have as crappy switches and still work just fine.
Hell, even the Sony, clarion, alpine, pioneer and other mid fi amps I have don’t suffer from this “flick a crossover switch, a fecking crossover switch, and have a blast of dc” syndrome...
Until Gordon delivers a miracle I’m going g to damn Soundstream and their lineage right down to the ores the materials were refined from...😡
I still want a Reference 200S though, no f£&king switches on that one...
And. Goliath tarantula, really want one of those too..
😱😱
Ok, I raised a glass to late speaker driver and have calmed down... 😀
The repair tech has indicated that the amp may have been under biased from new, he is offering to re-bias it for better sound quality.
Is this a good idea?
I also realise that I should have tested it more following post 39 so it’s my fault.
The repair tech has indicated that the amp may have been under biased from new, he is offering to re-bias it for better sound quality.
Is this a good idea?
I also realise that I should have tested it more following post 39 so it’s my fault.
If you can't see the distortion on the scope, you may be into the realm of subjectivity.
At this point, I think that these amps may have given you such a bad opinion that there is no way for you to every like them again. Much of what 'sounds good' is psychological.
At this point, I think that these amps may have given you such a bad opinion that there is no way for you to every like them again. Much of what 'sounds good' is psychological.
😀
Nah, I’ll be alright. I just wish I tested an obviously dodgy amplifier properly after being given a clear warning sign (the horrendous farting type noise on the left channel, in hindsight, was probably the clue) and not blown a rather nice vintage speaker. 🙂
I’m going to get Gordon to test it for distortion et al before repairing it and re testing, rather than just a power test. He mentioned some images on his website of Soundstream amp crossover distortion caused by underbiasing that seem reasonably convincing. In any event I do actually want to get a few more Soundstream amps, probably some higher end ones, it’s not fair to compare a affordably priced range 5 channel amp against high end stereo or four channel ones.
I mentioned preferring the sound of the Sony XM 3040F to the Soundstream and he pointed out it was biased higher and had a beefier power supply than the Soundstream. I didn’t ask him whether the output stages ( TIP Darlington Paris vs fully discrete) topology made a difference (the guy was at work... 😀) but anyway I feel one of the reference series or something ( I’m not too familiar with them as they are fairly rare over here) would make for a better comparison.
Also, it means I have a perfect reason to acquire more amps! 😀
Nah, I’ll be alright. I just wish I tested an obviously dodgy amplifier properly after being given a clear warning sign (the horrendous farting type noise on the left channel, in hindsight, was probably the clue) and not blown a rather nice vintage speaker. 🙂
I’m going to get Gordon to test it for distortion et al before repairing it and re testing, rather than just a power test. He mentioned some images on his website of Soundstream amp crossover distortion caused by underbiasing that seem reasonably convincing. In any event I do actually want to get a few more Soundstream amps, probably some higher end ones, it’s not fair to compare a affordably priced range 5 channel amp against high end stereo or four channel ones.
I mentioned preferring the sound of the Sony XM 3040F to the Soundstream and he pointed out it was biased higher and had a beefier power supply than the Soundstream. I didn’t ask him whether the output stages ( TIP Darlington Paris vs fully discrete) topology made a difference (the guy was at work... 😀) but anyway I feel one of the reference series or something ( I’m not too familiar with them as they are fairly rare over here) would make for a better comparison.
Also, it means I have a perfect reason to acquire more amps! 😀
From what I understand, SS bought all components in large qualities so they would be from the same batch, tested the biasing and adjusted as necessary for those components to get the biasing right. Replacement outputs and drivers can make the biasing too high or too low. Too low can result in distortion.
The type of output transistor has very little to do with the sound. The output at the speaker terminals is monitored by the feedback circuit and distortion is eliminated to a point of being inaudible. The exception to that is when the circuit is so far from normal that the circuit doesn't have enough drive to compensate.
The type of output transistor has very little to do with the sound. The output at the speaker terminals is monitored by the feedback circuit and distortion is eliminated to a point of being inaudible. The exception to that is when the circuit is so far from normal that the circuit doesn't have enough drive to compensate.
That would make sense given that some of the transistors seem to have been replaced already.
Possibly also the regulators, something might have been damaged by the rail voltage to case or by me or etc.
Could you recommend a Soundstream amp for me to keep an eye out for?
One that has impressed you with its build quality perhaps?
Possibly also the regulators, something might have been damaged by the rail voltage to case or by me or etc.
Could you recommend a Soundstream amp for me to keep an eye out for?
One that has impressed you with its build quality perhaps?